XE8000EV120 Semtech, XE8000EV120 Datasheet
XE8000EV120
Specifications of XE8000EV120
XM8000EV120
Related parts for XE8000EV120
XE8000EV120 Summary of contents
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... Pressure sensing (industrial, altimeter, diving computer) Chemical sensing (monitoring, security) Magnetic sensing (compass) ORDERING INFORMATION Part Number Temperature Range SX8722I070LF -40°C to 125°C Tools Part number Evaluation Kit XE8000EV120 BIAS AR1P AR1N AR2P AR2N AC7 AC6 AC5 Differential AC4 Single ended ...
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... Input multiplexers........................................................................................................................................... 25 9.3.1. Overview ................................................................................................................................................. 25 9.3.2. Input channel selection ........................................................................................................................... 25 9.3.3. Reference channel selection................................................................................................................... 26 9.3.4. Application example................................................................................................................................ 26 9.4. Programmable gain amplifier settings............................................................................................................ 28 9.4.1. Overview ................................................................................................................................................. 28 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 2 SX8722 DATASHEET Page www.semtech.com ...
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... Alarms............................................................................................................................................................ 44 11.5.1. Configuration register - alarms................................................................................................................ 44 11.5.2. Alarm threshold registers ....................................................................................................................... 44 11.5.3. SXCtrl2 - SX8722 Control register 2 ....................................................................................................... 45 11.6. I2C EEPROM................................................................................................................................................. 46 11.6.1. Overview ................................................................................................................................................. 46 11.6.2. Schematic ............................................................................................................................................... 46 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 3 SX8722 DATASHEET Page www.semtech.com ...
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... PGA Settling or Input Channel Modifications ................................................................................................ 71 12.13. PGA Gain & Offset, Linearity and Noise ....................................................................................................... 71 12.14. Power Reduction ........................................................................................................................................... 71 12.15. Noise ............................................................................................................................................................. 72 12.16. Gain Error and Offset Error ........................................................................................................................... 73 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 4 SX8722 DATASHEET Page www.semtech.com ...
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... PCB Layout Considerations................................................................................................................................. 105 17. How to Evaluate................................................................................................................................................... 105 18. Package Outline Drawing: MLPQ44-7x7mm ....................................................................................................... 105 19. Land Pattern Drawing: MLPQ44-7x7mm............................................................................................................. 106 20. Tape and Reel Specification................................................................................................................................ 107 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 5 SX8722 DATASHEET Page www.semtech.com ...
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... CURENT CONSUMPTION Active current Sleep current (1) Sleep current (2) Shutdown current DIGITAL I/O Input logic high Input logic low Output logic high Output logic low ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Symbol Condition V BAT T STORE ...
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... PGA3 Offset Offset Settings Precision (PGA2 or PGA3) Offset Temperature Dependance Input Impedance PGA1 Input Impedance PGA2 ,PGA3 Output RMS Noise ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface = +25° +5V, GND = 0V BATT = 1, offsets GD TOT COMMENTS/CONDITIONS Gain = 1, OSR = 32 (Note 1) ...
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... TIME BASE Max ADC oversampling frequency Min ADC oversampling frequency DIGITAL OUTPUT ADC Output Data Coding TEMPERATURE Specified Range Operating Range ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface COMMENTS/CONDITIONS n (Note 7) (Note 8) (Note bits (Note 10) INL ...
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... Bias currents in PGAs and ADC set to 1/2 of nominal values, i.e. IB_AMP_PGA[1:0] = '01', IB_AMP_ADC[1:0] = '01'. (19) Bias currents in PGAs and ADC set to 1/4 of nominal values, i.e. IB_AMP_PGA[1:0] = '00', IB_AMP_ADC[1:0] = '00'. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface = 256 kHz, 4 for ...
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... Pin configuration NC SLEEP SHUT READY BIAS EE_POW EE_SDA EE_SCL 2.2. Marking information nnnnnn = Part Number (Example: SX8722) yyww = Date Code (Example: 0752) xxxxxxxxx = Semtech Lot No. (Example A01E90101) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface ...
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... Analog input 23 AC7 Analog input ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Function Not connected Setting this pin to 0 puts the SX8722 in sleep mode, power consumption ~1.5uA, otherwise the pin can be floating Setting this pin to 0 puts the SX8722 in shutdown mode, power consumption ~0 ...
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... XIN Digital input 39 XOUT Digital output 40 DNC 41 DNC 42 CAL Digital input ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Function TM ZoomingADC input 6 TM ZoomingADC input 5 TM ZoomingADC input 4 TM ZoomingADC input 3 TM ZoomingADC input 2 TM ...
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... All timings specifications are referred to VILMIN and VIHMAX voltage levels defined for the SCL and SDA pins. With 32’768 Hz Xtal presence. 4.1. I2C timing Waveforms SDA SCL SDA SCL ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Symbol Condition f SCL t LOW t ...
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... Figure 3. Start-up timing diagram with EEPROM loading 4.4. Changing power mode by pin signal Table 2. Power mode changing timings by pin setting (1) instantaneous ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface time after EEPROM loading: 140 [ms] From SHUT ...
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... When time to change a power mode is instantaneous, it doesn't mean that the chip is totally ready to work. There are for example initialization times, EEPROM loading or code execution. The transition time is considered as not low power. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface From SHUT SLEEP ...
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... The major modules of the SX8722 are the ZoomingADC™, the signal post processing, the control unit and the power management The SX8722 offers several configuration possibilities allowing the developer to use peripheral of its system or to use stand alone system generating alarms. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface SX8722 BIAS AC0 AC1 ...
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... The SX8722 implements 4 configuration register sets. Each of these sets completely defines the behavior of the ZoomingADC™. This allows the user to preset 4 different measurement configurations that can be activated by setting a single bit. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 17 SX8722 DATASHEET ...
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... The measurement engine copies the configuration register sets in the ZoomingADC™ physical registers and writes back the conversion results. The communication engine controls read/write access from the I2C or the external EEPROM. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Alarms Control & Configuration ...
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... Over sampling rates and elementary conversion combinations allow setting the ideal resolution for the ideal conversion time. E. Measurement engine Manages ZoomingADC™ configurations. Updates the measured values. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 0/12 to 127/ ...
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... EEPROM save_eeprom load_eeprom ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Description Writes 8bit data to a given address Writes bits to given address using a given mask Reads 8bit data from a given address Sets the SX8722 to sleep mode ...
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... The diagram below shows the write operation at successive addresses (burst mode DEVICE ADDRESS E SDA Figure 8. I2C frame: write burst register, command 0x10 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface REGISTER T COMMAND ADDRESS REGISTER COMMAND ADDRESS ...
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... If a read sequence is initiated without sending previously an address, the data shifted out will be the latest conversion result and its corresponding configuration ID (24 bits). See next page for more information. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface REGISTER COMMAND ...
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... When the SX8722 is addressed and read the output is as shown below. Config ID indicates which channel is shifted out DEVICE T ADDRESS SDA Figure 13. I2C frame: reading after a measurement ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface DEVICE T COMMAND ADDRESS T E ...
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... D. The ADC E. The Measurement engine Note: Grayed out blocks in the schematic means that they are used in the current function. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface st configuration register set, use the registers definition 0/12 to 127/12 ...
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... The diagram above shows the input multiplexer organization; these are enabling the selection of both the input and the reference sources. 9.3.2. Input channel selection The following settings allow configuring the input multiplexers of the ZoomingADC™ ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 0/12 to 127/12 + ...
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... Note: This command can be optimized, since the reference and input setting are sharing the same address the mask and the settings can be added. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Function Address Data AC0 - AC1 ...
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... ADVANCED COMMUNICATIONS & SENSING The following command shows the optimized way ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Function Address Data Set input to 0x0F 0x00 AC1 - AC0, set reference to AR1P - AR1N Table 10. Optimized command ...
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... The diagram above shows the programmable gain amplifier organization, these are 3 PGA that are cascaded, the gain is made by multiplying them (disabled PGAs have the equivalent gain of 1). ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface ...
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... The diagram below shows the flow to set the gain of your configuration: Set gain Gain < Yes Enable PGA3 Set PGA 3 gain GAIN = PGA3 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface No Gain < 100 ? Yes Enable PGA2&3 Set PGA 2 gain Set PGA 3 gain GAIN = ...
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... ADVANCED COMMUNICATIONS & SENSING 9.4.3. Enable/disable PGAs 9.4.4. PGA3 gain configuration 9.4.5. PGA2 gain configuration ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Function Address Data Enable PGA3 0x0B 0x08 Disable PGA3 0x00 Enable PGA2&3 0x0A Disable PGA2& ...
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... This command can be optimized, since PGA1 and PGA3 gains are sharing the same address the mask and the settings can be added. The following list of settings shows the optimized Table 16. Optimized command of PGA gain settings ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Function Address Data Gain = 1 ...
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... More offsets configuration can be defined using the "advanced configuration" at the end of this document. The drawings below explain the offset concept. (AC1 – AC0) Vref / Vref / 2 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 0/12 to 127/ ...
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... ADVANCED COMMUNICATIONS & SENSING (AC1 – AC0) Vref 0 The following settings add 0 REF ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Vref / 2 OFFSET 0.5 x Vref t - Vref / 2 Figure 20. Single ended signal, AC0 = V or subtract 0 from the signal. ...
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... REF Input selection = AC0 - AC1. (see "input multiplexers" chapter) Offset to remove REF The following command must be sent to SX8722: Offset ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Function Address Data 0x0E 0x06 REF Function ...
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... The table below gives the main configurations available using the predefined settings and their main characteristics: Name Resolution Conversion time [bits] [ms] (typ) S16 16 27.3 N16 16 F16 16 N12 12 0. 0.06 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 0/12 to 127/ PGA1 PGA2 PGA3 - - - 5/5 63/12 ... ... -5/5 -63/12 + ...
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... All the predefined settings refer to configuration 1, to change other configurations simply adapt the address value. More detailed functionalities are described in “Advanced configuration” chapter. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Address Data 0x0C ...
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... ADVANCED COMMUNICATIONS & SENSING 9.7.2. Measurement engine settings Configuration 1 enabled Configuration 1 disabled ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Application Address Data 0x02 0x01 0x00 Table 21. Measurement engine settings Page 37 SX8722 DATASHEET Mask 0x01 ...
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... Differential measurement on channel AC0 - AC1, gain 1, 16 bits resolution, reference on AR1P - AR1N, no filtering, continuous measurements. The READY pin will pulse from "0" to "1" at every sample available. The host microcontroller can then read the data. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface SX8722 TM ZoomingADC ...
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... The advanced configuration section is entering more in depth in the SX8722 usage. In this section you will find: Measurement engine Configuration control Filtering Alarms I2C EEPROM Using the SX8722 Stand alone Calibration process Working below 3 Volts Control registers ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 39 SX8722 DATASHEET www.semtech.com ...
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... If in one or more configurations the bit CONT is set to 1, the measurements are performed again until the CONT bit is set to 0 through the I2C interface. The engine goes out from the Idle mode every time an event occurs on the I2C interface. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface YES Store intermediate values ...
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... AL1OnC 2 AL1OffC 1 AL2OnC 0 AL2OffC Note: More information about the alarms condition usage on Alarm section ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 5 4 CKOUT reserved Table 22. Control register; address 0x00 rw Reset r x Indicates if an EEPROM was detected at startup ...
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... The bit SINGLE is set by the user, once the measurement is done; the measurement engine clears the CONF bit of the configuration. The bit CONT is set by the user, the measurement is done continuously until this bit is cleared by the user. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 5 4 reserved ...
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... CxSXCfg reserved Table 27. Filtering mode in configuration registers; addresses 0x10, 0x30, 0x50, 0x70 The table below shows the filter selection. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 5 4 FILTER TYPE[2:0] ALRM1 Filter type [6:4] Code ...
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... CxAlrm1OnMsb CxAlrm1OnLsb CxAlrm1OffMsb CxAlrm1OffLsb CxAlrm2OnMsb CxAlrm2OnLsb CxAlrm2OffMsb CxAlrm2OffLsb Table 31. Alarm threshold registers; addresses 0x12 to 0x19, 0x32 to 0x39, 0x52 to 0x59 and 0x72 to 0x79 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 5 4 Filter size [7: FILTER TYPE [2: ...
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... Configuration 3 Alarm1 off threshold reached ? Configuration 4 Alarm1 off threshold reached ? The flowchart below shows the management of the alarms flag (when at least one alarm is on). ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface 5 4 reserved reserved AL1OnC Figure 24 ...
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... AR1P AR1N AR2P AR2N AC7 AC6 AC5 Differential AC4 AC3 AC2 AC1 AC0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface SX8722 TM ZoomingADC PGA ADC POST-PROCESS Figure 26. EEPROM connection Page 46 SX8722 DATASHEET EEPROM VBATT VBATT ...
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... AR1N AR2P AR2N AC7 AC6 AC5 Differential AC4 AC3 AC2 AC1 AC0 Figure 27. Example of stand alone configuration ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface EEPROM TM ZoomingADC CONTROL PGA ADC OSC POWER POST-PROCESS Page 47 SX8722 ...
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... AR2P AR2N AC7 AC6 AC5 Differential AC4 AC3 AC2 AC1 AC0 Figure 28. Calibration : using a 32’768 Hz XTAL ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface TM ZoomingADC CONTROL PGA ADC POWER POST-PROCESS Page 48 SX8722 DATASHEET 5V VBATT ...
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... Figure 29. Calibration : using a 32’768 Hz signal NOTE external EEPROM is present, the calibration value is saved in it. The tolerance signal must remain around 32.768 kHz +/- 10% ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface TM ZoomingADC CONTROL PGA ADC ...
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... AR2N AC7 AC6 AC5 Differential AC4 AC3 AC2 AC1 AC0 Figure 30. SX8722 working below 3V schematic ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface TM ZoomingADC CONTROL PGA ADC POWER POST-PROCESS Page 50 SX8722 DATASHEET Vbatt < 3V VBATT ...
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... The figure above shows the general block diagram of the acquisition chain (AC). Analog inputs can be selected among eight input channels, while reference input is selected between two differential channels. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface + + + ...
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... The sampling frequency to throughput ratio is large (typically 10-500). These converters include digital decimation filtering. They are mainly used for high resolution, and/or low-to-medium speed applications. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface and V , the input voltage is modulated and amplified through stages ...
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... CxAdcReg6 CxAdcReg5 CxAdcReg4 CxAdcReg3 CxAdcReg2 CxAdcReg1 Figure 32. ZoomingADC detailed functional block diagram ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface PGA1 PGA2 - - - V REF + OFF2 - Sampling frequency fs Power Saving Modes PGA Enabling Nb of elementary cycles Oversampling ratio ...
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... IB_AMP_ADC[1:0] 5:4 IB_AMP_PGA[1:0] 3:0 ENABLE[3:0] Table 35. CxZadcReg2; addresses 0x0B - 0x2B - 0x4B - 0x6B ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Registers Addresses CxZadcReg1 0x0A - 0x2A - 0x4A - 0x6A CxZadcReg2 0x0B - 0x2B - 0x4B - 0x6B CxZadcReg3 0x0C - 0x2C - 0x4C - 0x6C ...
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... CxZadcReg6 7 PGA1_GAIN 6 PGA3_PGA[6:0] 5:1 AMUX[4:0] 0 VMUX Table 39. CxZadcReg6; addresses 0x0F - 0x2F - 0x4F - 0x6F ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface rw Reset rw 00 Sampling frequency selection rw 00 PGA2 stage gain selection rw 0000 PGA2 stage offset selection ...
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... These bits set the sampling frequency of the acquisition chain. Expressed as a fraction of the oscillator frequency, the sampling frequency is given as 1/4 f PGA1_GAIN: (rw) sets the gain of the first stage 10. PGA2_GAIN: (rw) sets the gain of the second stage 10. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Bit position OUT[7:0] OUT[15:8] ...
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... AMUX [4:0] (RegACCfg5[5:1]) 00x00 00x01 00x10 00x11 10000 10001 10010 10011 10100 10101 10110 10111 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface AMUX [4:0] INP INN (RegACCfg5[5:1]) AC_A(1) AC_A(0) 01x00 AC_A(3) AC_A(2) 01x01 AC_A(5) ...
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... The first stage can have a buffer function (unity gain) or provide a gain of 10 (see Table 44). The voltage V PGA1 is: = ⋅ (Eq. 5) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface VMUX V REFP (RegACCfg5[0]) 0 AC_R(1) 1 AC_R(3) Table 42. Analog input reference selection Enable [3:0] Block XXX0 ...
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... D 1 (Eq. 6) where GD2 and GDoff2 are respectively the gain and offset of PGA2 (in V/V). These are controlled with the words PGA2_GAIN[1:0] and PGA2_OFFSET[3:0]. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface PGA1_GAIN PGA1 gain [V/ Table 44. PGA1 gain settings ⋅ ...
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... ADVANCED COMMUNICATIONS & SENSING 12.7.4. PGA3 The finest gain and offset tuning is performed with the third and last PGA stage, according to the following coding Tables. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface PGA2_OFFSET PGA2 offset [V/V] 1100 -1 Table 46 ...
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... Finally, combining equations Eq Eq. 7 for the three PGA stages, the input voltage V by: = ⋅ − GDoff IN , ADC TOT IN (Eq. 9) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface PGA3_GAIN[6:0] PGA3 gain [V/V] 1000000 0 1000001 -1/12(=-0.083) 1000010 -2/12 ... ... 1010000 -16/12 ... ... 1100000 -32/12 ...
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... Thus, converter internal offset is eliminated if at least two elementary sequences are performed (i. additional clock cycles are also required to initiate and end the conversion properly. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface ⋅ ⋅ ...
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... The over-sampling ratio (OSR) defines the number of integration cycles per elementary conversion. Its value is set with the word SET_OSR[2:0] in power of 2 steps (see Table 49) given by SET_OSR[2 = OSR 2 (Eq. 13) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface T = (OSR+1)/f ELCONV S Elementary Elementary Conversion Conversion 1 ...
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... The theoretical resolution of the ADC, without considering thermal noise, is given by: = ⋅ log ( OSR ) log ( 2 2 (Eq. 15) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface SET_OSR[2:0] Over-Sampling Ratio (RegACCfg[4:2]) OSR [-] 010 32 011 64 100 128 101 256 110 512 111 1024 Table 50 ...
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... OSR and N noise in the PGA . 12.8.6. Conversion Time & Throughput As explained using Figure 3, conversion time is given by: = ⋅ OSR CONV ELCONV (Eq. 16) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface SET_NELC 000 001 010 ...
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... Table 53. Normalized conversion time (T Table 54. Resolution vs. normalized conversion time for different SET_NELC[1:0] ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface . For example, consider an over-sampling ratio of 256, 2 elementary conversions, and SET_NELC ...
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... GDoff GDoff GD TOT 3 ADC Input Voltage V IN,ADC +2.49505 V +2.49497 V ... +76.145 μ -76.145 μ V ... ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface + OSR LSB OSR ⎞ OSR 1 ⎟ ⎟ ⋅ ⋅ REF [ LSB TOT V OSR ⎠ ...
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... Notice that the input voltage V IN,ADC 1 ≤ ⋅ − ADC REFP REFN 2 (Eq. 20) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface % of Full Scale (FS) Output in LSBs ... -32’767 -0 -32’768 SET_NELC = 01 100000000 10000000 1000000 100000 10000 1000 ...
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... Therefore, with a gain of 1 and a sampling frequency of 75 kHz, Zin > 10.2 MOhm. The input impedance on channels that are not selected is very high (>100MOhm). ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface IB_AMP_PGA ADC Bias ...
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... Measuring the sensor node will show short voltage spikes at the frequency fs, but these will not influence the measurement. Whereas if the bandwidth of the node is ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface V f ...
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... Disable all PGAs and the ADC when the system is idle and no conversion is performed. 4. Use lower bias currents in the PGAs and the ADC using the control words IB_AMP_PGA[1:0] and IB_AMP_ADC[1:0]. 5. Reduce sampling frequency. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface . BATT ...
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... Table 58. PGA Noise Measurements ( bits, OSR = 512, N Figure 37. ADC Noise (PGA1, 2 & 3 Bypassed, OSR = 512, N ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface should result in a constant output code. However, because of circuit noise, the output 2 2 ⎞ ...
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... Finally, these gain errors can be calibrated by the software at the same time with the gain errors of the sensor for instance. Figure 40 shows gain error drift vs. temperature for different PGA gains. The curves are expressed Full-Scale Range (FSR) normalized to 25°C. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface PGA2 PGA3 V V ...
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... Temperature [°C] Figure 40. Gain Error vs. Temperature for Different PGA Gains ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface > 1. ELCONV 100 100 50 75 100 Figure 41. Offset Error vs. Temperature for Different PGA Gains ...
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... SX8722 measured current consumption: ~330 µA Example 2 : Bias current 100% PGA1: enabled PGA2: enabled PGA3: enabled SX8722 measured current consumption: ~710 µA ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Current for each amplifier in [uA PGA1 PGA2 bias 25 % ...
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... PGA1 off; PGA2 off; PGA3 = 10; set_osr = 7; set_nelconv = 3; VBAT = 5V; Vref = 5V; Vcommon = - 100 150 200 Vin [mV] ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface ADC without PGA 25°C PGA1 off; PGA2 off; PGA3 off; set_osr = 7; set_nelconv = 3; Vbat = 5V; Vref = 5V; Vcommon = -10 2500 0 500 1000 ...
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... Figure 42. INL over temperature for different gains 13.2.2. Differential non-linearity DNL: significantly lower than one LSB ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Gain 100 25°C PGA1 off; PGA2 = 10; PGA3 = 10; set_osr = 7; set_nelconv = 3; VBAT = 5V; Vref = 5V; Vcommon = 0V ...
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... ADVANCED COMMUNICATIONS & SENSING 13.2.3. Resolution vs acquisition time ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface resolution vs acquisition time 100 1000 time [us] Figure 44. ADC resolution vs Acquisition time Page 78 SX8722 DATASHEET 10000 100000 www.semtech.com ...
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... C1Alrm1OnLsb 0x14 C1Alrm1OffMsb 0x15 C1Alrm1OffLsb 0x16 C1Alrm2OnMsb 0x17 C1Alrm2OnLsb ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Bit SX8722 General Configuration 8 Configuration register of the SX8722 8 Configuration register of the SX8722 8 Configuration enable register,enables configurations from Updated value on configuration registers ...
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... C3ZAdcReg3 0x4D C3ZAdcReg4 0x4E C3ZAdcReg5 0x4F C3ZAdcReg6 0x50 C3SXCfg 0x51 C3FParam ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Bit 16 Alarm 2 "OFF" threshold 16 Configuration 1 data out Configuration 2 8 ZoomingADC Register 01 8 ZoomingADC Register 02 8 ZoomingADC Register 03 ...
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... C4Alrm2OnMsb 0x77 C4Alrm2OnLsb 0x78 C4Alrm2OffMsb 0x79 C4Alrm2OffLsb 0x7A C4DataOutMsb 0x7B C4DataOutLsb ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Bit 16 Alarm 1 "ON" threshold 16 Alarm 1 "OFF" threshold 16 Alarm 2 "ON" threshold 16 Alarm 2 "OFF" threshold 16 Configuration 3 data out ...
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... Bit Name 7:4 reserved 3 CONF4 2 CONF3 1 CONF2 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset r x Indicates if an EEPROM was detected at startup r x Indicates if an XTAL was detected at startup rw 0 Enabled the clock output on CKOUT pin ...
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... UCONF4 2 UCONF3 1 UCONF2 0 UCONF1 Bit Name 7:0 Fine RC Bit Name 7:0 Coarse RC ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 0 Configuration 1 enabling Table 62. SXCfgEn (0x02) Mode Reset r 0 Overflow on configuration Overflow on configuration 3 r ...
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... PGA2_GAIN[1:0] 3:0 PGA2_OFFSET[3:0] Bit Name 7 PGA1_GAIN 6:0 PGA3_GAIN[6:0] ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset Sets the number of elementary conversion to 2 compensate for offset the signal is chopped between elementary conversion. rw 010 ...
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... FILTER TYPE [2:0] 3 ALRM1 2 ALRM2 1 SINGLE 0 CONT Bit Name 7:0 SIZE ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset r 0 Unused rw 0000000 PGA3 stage offset selection Table 70. C1ZAdcReg5 (0x0E) Mode Reset 00000 ...
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... Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 00000000 Alarm 1 threshold MSB for configuration 1 Table 74. C1Alrm1OnMsb (0x12) Mode Reset rw 00000000 Alarm 1 threshold LSB for configuration 1 Table 75 ...
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... Bit Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Table 80 C1Alrm1OffMsb (0x18) Mode Reset rw 00000000 Alarm 2 threshold LSB for configuration 1 Table 81. C1Alrm1OffLsb (0x19) Mode Reset r 00000000 Configuration 1 data out MSB Table 82 ...
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... PGA2_GAIN[1:0] 3:0 PGA2_OFFSET[3:0] Bit Name 7 PGA1_GAIN 6:0 PGA3_GAIN[6:0] ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset Sets the number of elementary conversion to 2 compensate for offset the signal is chopped between elementary conversion. rw 010 ...
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... FILTER TYPE [2:0] 3 ALRM1 2 ALRM2 1 SINGLE 0 CONT Bit Name 7:0 SIZE ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset r 0 Unused rw 0000000 PGA3 stage offset selection Table 88. C2ZAdcReg5 (0x2E) Mode Reset 00000 ...
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... Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 00000000 Alarm 1 threshold MSB for configuration 2 Table 92. C2Alrm1OnMsb (0x32) Mode Reset rw 00000000 Alarm 1 threshold LSB for configuration 2 Table 93 ...
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... Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 00000000 Alarm 2 threshold MSB for configuration 2 Table 98 C2Alrm1OffMsb (0x38) Mode Reset rw 00000000 Alarm 2 threshold LSB for configuration 2 Table 99 ...
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... PGA2_GAIN[1:0] 3:0 PGA2_OFFSET[3:0] Bit Name 7 PGA1_GAIN 6:0 PGA3_GAIN[6:0] ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset Sets the number of elementary conversion to 2 compensate for offset the signal is chopped between elementary conversion. rw 010 ...
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... FILTER TYPE [2:0] 3 ALRM1 2 ALRM2 1 SINGLE 0 CONT Bit Name 7:0 SIZE ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset r 0 Unused rw 0000000 PGA3 stage offset selection Table 106. C3ZAdcReg5 (0x4E) Mode Reset 00000 ...
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... Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 00000000 Alarm 1 threshold MSB for configuration 3 Table 110. C3Alrm1OnMsb (0x52) Mode Reset rw 00000000 Alarm 1 threshold LSB for configuration 3 Table 111 ...
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... Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 00000000 Alarm 2 threshold MSB for configuration 3 Table 116 C3Alrm1OffMsb (0x58) Mode Reset rw 00000000 Alarm 2 threshold LSB for configuration 3 Table 117 ...
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... PGA2_GAIN[1:0] 3:0 PGA2_OFFSET[3:0] Bit Name 7 PGA1_GAIN 6:0 PGA3_GAIN[6:0] ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset Sets the number of elementary conversion to 2 compensate for offset the signal is chopped between elementary conversion. rw 010 ...
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... FILTER TYPE [2:0] 3 ALRM1 2 ALRM2 1 SINGLE 0 CONT Bit Name 7:0 SIZE ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset r 0 Unused rw 0000000 PGA3 stage offset selection Table 124. C4ZAdcReg5 (0x6E) Mode Reset 00000 ...
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... Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 00000000 Alarm 1 threshold MSB for configuration 4 Table 128. C4Alrm1OnMsb (0x72) Mode Reset rw 00000000 Alarm 1 threshold LSB for configuration 4 Table 129 ...
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... Name 7:0 Bit Name 7:0 Bit Name 7:0 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Mode Reset rw 00000000 Alarm 2 threshold MSB for configuration 4 Table 134 C4Alrm1OffMsb (0x78) Mode Reset rw 00000000 Alarm 2 threshold LSB for configuration 4 Table 135 ...
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... The timing of the transition states depends mainly on the Xtal presence, the EEPROM presence and if the transition is caused by an I2C command pin signal (SLEEP, SHUT, RESET). ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 100 SX8722 DATASHEET www ...
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... VLD stopped (voltage level detector) If Xtal present, clock set to Xtal 32k If Xtal not present, clock set to RC minimum value (~80kHz) Bias current off ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 101 SX8722 DATASHEET www.semtech.com ...
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... There are pulses on the READY pin in active mode every 36ms. In sleep mode there is no pulse on the READY pin. 15.3.7. Wake up from sleep mode to active mode ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 102 SX8722 DATASHEET www ...
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... Send the 0x50 command through the I2C interface. I2C SHUT bit toggle Through the I2C interface, send a write mask command at address 00 and toggle the SHUT bit of the SXCtrl1 register. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 103 SX8722 DATASHEET ...
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... In both case the RAM information is lost. SX8722 configuration must be restored from the EEPROM saved configuration. 15.4.5. Change from shutdown mode to sleep mode This is not possible. ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface Page 104 SX8722 DATASHEET ...
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... How to Evaluate For evaluation purposes the XE8000EV120 evaluation kit can be ordered. This kit connects to any PC using a USB port. The "SX8722 Evaluation Tools" software gives the user the ability to control the SX8722 and displaying configurations on the " ...
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... ADVANCED COMMUNICATIONS & SENSING 19. Land Pattern Drawing: MLPQ44-7x7mm (C) ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface H DIM NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. ...
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... Tape Width (W) 2x2 8 3x3 12 4x4 12 4x3 12 5x5 12 6x6 16 6x5 12 7x7 16 9X9 16 10x10 24 11x11 24 ACS - Revision 4.2 October 2008 ©2008 Semtech Corp. High gain acquisition for sensor interface carrier tape (mm) Pocket Reel Pitch Size (P) (in) 4 2.25 2.25 1. 3.30 3.30 1. 4.35 4.35 1. ...
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... No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent or other industrial or intellectual property rights. Semtech assumes no responsibility or liability whatsoever for any failure or unexpected operation resulting from misuse, neglect improper installation, repair or improper handling or unusual physical or electrical stress including, but not limited to, exposure to parameters beyond the specified maximum ratings or operation outside the specified range ...