LTC2413 LINER [Linear Technology], LTC2413 Datasheet
LTC2413
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LTC2413 Summary of contents
Page 1
... INL and 0.16ppm RMS noise. It uses delta-sigma technology and provides single cycle settling time for multiplexed applications. Through a single pin, the LTC2413 can be configured for better than 87dB input differential mode rejection over the range of 49Hz to 61.2Hz (50Hz and 60Hz 2% simultaneously can be driven by an external oscillator for a user defined rejection frequency ...
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... GND .................................... – 0. Digital Input Voltage to GND ........ – 0. Digital Output Voltage to GND ..... – 0. Operating Temperature Range LTC2413C ............................................... LTC2413I ............................................ – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T ...
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... CONDITIONS + Voltage – Voltage + Voltage – Voltage + GND CC – GND REF = 5V CC – REF = GND CC LTC2413 MIN TYP MAX UNITS 130 140 dB 140 110 140 dB 130 140 dB 120 dB 120 dB MIN TYP MAX UNITS GND – 0. ...
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... LTC2413 U U DIGITAL I PUTS A D DIGITAL OUTPUTS operating temperature range, otherwise specifications are at T SYMBOL PARAMETER V High Level Input Voltage IH CS Low Level Input Voltage IL CS High Level Input Voltage IH SCK V Low Level Input Voltage IL SCK I Digital Input Current ...
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... SCK pin is used as digital output. Note 10: The external oscillator is connected to the F oscillator frequency, f Note 11: The converter uses the internal oscillator. F Note 12: The output noise includes the contribution of the internal calibration operations. Note 13: Guaranteed by design and test correlation. LTC2413 MIN TYP MAX UNITS 2.56 2000 ...
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... LTC2413 W U TYPICAL PERFOR A CE CHARACTERISTICS Total Unadjusted Error vs Temperature ( 5V) REF 1.5 1.0 0 REF = 5V –0.5 – REF = GND REF T = – –1 2.5V INCM F = GND O –1.5 –2.5 –2 –1.5 –1 –0.5 0 0.5 1 1.5 2 2.5 V (V) IN 2413 G01 ...
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... REF = 2.5V REF – REF = GND –0 GND O –1 TIME (HOURS) 2413 G17 LTC2413 Noise Histogram (Output Rate = 52.5Hz 5V 2.5V) CC REF 12 10,000 CONSECUTIVE GAUSSIAN READINGS DISTRIBUTION 3.852ppm 2.5V = 0.326ppm REF ...
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... LTC2413 W U TYPICAL PERFOR A CE CHARACTERISTICS RMS Noise vs V INCM 850 825 800 775 REF = 5V 750 – REF = GND 725 REF + INCM – INCM 700 GND O 675 650 –0.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 V (V) ...
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... IN = GND – GND – GND –60 –80 –100 –120 –140 1 10 100 1k 10k 100k 1M FREQUENCY AT V (Hz) CC 2413 G35 LTC2413 – Full-Scale Error vs Temperature ( REF = 5V 2 – REF = GND + IN = GND – 2. GND O 0 –1 –2 – ...
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... LTC2413 W U TYPICAL PERFOR A CE CHARACTERISTICS Conversion Current vs Temperature ( 220 F = GND GND SCK = NC 210 SDO = 5.5V CC 200 190 V = 4.1V CC 180 V = 2.7V CC 170 160 –45 –30 – TEMPERATURE ( C) 2413 G37 CTIO S GND (Pins 10, 15, 16): Ground. Multiple ground ...
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... U APPLICATIO S I FOR ATIO CONVERTER OPERATION Converter Operation Cycle The LTC2413 is a low power, delta-sigma analog-to- digital converter with an easy to use 3-wire serial interface. Its operation is made up of three states. The converter operating cycle begins with the conversion, followed by the low power sleep state and ends with the data output (see Figure 2) ...
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... The POR signal clears all internal registers. Following the POR signal, the LTC2413 starts a normal conversion cycle and follows the succession of states described above. The first conversion result following POR is accurate within the specifications of the device if the power supply voltage is restored within the operating range (2 ...
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... V This error has a very strong temperature dependency. Output Data Format The LTC2413 serial output data stream is 32 bits long. The first 3 bits represent status information indicating the sign and conversion state. The next 24 bits are the conversion result, MSB first ...
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... F – pins is maintained When a fundamental rejection frequency different from the range 49Hz to 61.2Hz is required or when the converter must be sychronized with an outside source, the LTC2413 to REF can operate with an external conversion clock. The conveter automatically detects the presence of an external clock ...
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... EOSC Whenever an external clock is not present at the F converter automatically activates its internal oscillator and enters the Internal Conversion Clock mode. The LTC2413 operation will not be disturbed if the change of conversion clock source occurs during the sleep state or during the data output state while the converter uses an external serial clock ...
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... SDO pin on the falling edge of the serial clock. In the Internal SCK mode of operation, the SCK pin is an output and the LTC2413 creates its own serial clock by dividing the internal conversion clock the External SCK mode of operation, the SCK pin is used as input. The ...
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... GND BIT 31 BIT 30 BIT 29 BIT 28 BIT 27 BIT 26 EOC SIG MSB DATA OUTPUT Figure 6. External Serial Clock, Single Cycle Operation LTC2413 exceeds 2.2V. The level CC = EXTERNAL OSCILLATOR = INTERNAL OSC/SIMULTANEOUS 50Hz/60Hz REJECTION 3-WIRE SPI INTERFACE TEST EOC BIT 5 BIT 0 LSB SUB LSB Hi-Z ...
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... In order to select the internal serial clock timing mode, the serial clock pin (SCK) must be floating (Hi-Z) or pulled HIGH prior to the falling edge of CS. The device will not 2. LTC2413 3 + REFERENCE 13 REF SCK VOLTAGE 4 – 0. REF ...
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... 10, 15, 16 GND BIT 30 BIT 29 BIT 28 BIT 27 BIT 26 SIG MSB DATA OUTPUT Figure 9. Internal Serial Clock, Single Cycle Operation LTC2413 = EXTERNAL OSCILLATOR = INTERNAL OSC/SIMULTANEOUS 50Hz/60Hz REJECTION 2-WIRE I/O BIT 26 BIT 5 BIT 0 LSB EXTERNAL OSCILLATOR = INTERNAL OSC/SIMULTANEOUS 10k 50Hz/60Hz REJECTION ...
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... SCK pin or by never pulling CS HIGH when SCK is LOW. Whenever SCK is LOW, the LTC2413’s internal pull-up at pin SCK is disabled. Normally, SCK is not externally driven if the device is in the internal SCK timing mode. However, certain applications may require an external driver on SCK ...
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... TO V REF ANALOG INPUT RANGE + IN SDO –0.5V TO 0.5V REF REF 6 11 – 10, 15, 16 GND BIT 29 BIT 28 BIT 27 BIT 26 SIG MSB DATA OUTPUT LTC2413 = EXTERNAL OSCILLATOR = INTERNAL OSC/SIMULTANEOUS 50Hz/60Hz REJECTION 2-WIRE I/O BIT 5 BIT 0 LSB 24 CONVERSION sn2413 2413fs 21 2413 F11 ...
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... PCB surface. The internal serial clock mode is selected every time the voltage on the CS pin crosses an internal threshold volt- age. An internal weak pull-up at the SCK pin is active while 2. LTC2413 3 + REFERENCE 13 REF SCK VOLTAGE 4 – REF 0. ...
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... CMOS levels [V (V – 0.4V)]. CC During the conversion period, the undershoot and/or overshoot of a fast digital signal connected to the LTC2413 pins may severely disturb the analog to digital conversion process. Undershoot and overshoot can occur because of 10000 100000 the impedance mismatch at the converter pin when the ...
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... F the differential input and reference connections. Driving the Input and Reference The input and reference pins of the LTC2413 converter are directly connected to a network of sampling capacitors. Depending upon the relation between the differential input voltage and the differential reference voltage, these ca- pacitors are switching between these four pins transfering small amounts of charge in the process ...
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... EOSC The effect of this input dynamic current can be analyzed using the test circuit of Figure 17. The C includes the LTC2413 pin capacitance (5pF typical) plus the capacitance of the test fixture used to obtain the results shown in Figures 18 and 19. A careful implementation can bring the total input capacitance (C ...
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... C are unavoidably present as parasitics IN of input multiplexers, wires, connectors or sensors, the LTC2413 can maintain its exceptional accuracy while operating with relative large values of source resistance as shown in Figures 18 and 19. These measured results may be slightly different from the first order approximation ...
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... Large C IN SOURCEIN SOURCEIN W U Reference Current In a similar fashion, the LTC2413 samples the differential reference pins REF charge to and from the external driving circuits, thus produces a dynamic reference current. This current does not change the converter offset but it may degrade the gain and INL performance ...
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... LTC2413 U U APPLICATIO S I FOR ATIO Figure 27 shows the typical INL error due to the source + – resistance driving the REF or REF values are used. The effect of the source resistance on the two reference pins is additive with respect to this INL error. In general, matching of source impedance for the REF – ...
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... Reference Source Resistance (R Large C Output Data Rate When using its internal oscillator, the LTC2413 can pro- duce up to 6.8 readings per second. The actual output data rate will depend upon the length of the sleep and data output phases which are controlled by the user and which can be made insignificantly short ...
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... LTC2413 U U APPLICATIO S I FOR ATIO Third, an increase in the frequency of the external oscilla- tor above 460800Hz (a more than 3 increase in the output data rate) will start to decrease the effectiveness of the internal autocalibration circuits. This will result in a pro- gressive degradation in the converter accuracy and linear- ity ...
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... REF INCM 10 –0.5V • V < V < 0.5 • V REF IN REF F = EXTERNAL OSCILLATOR 100 OUTPUT DATA RATE (READINGS/SEC) 1LSB) vs Output Data Rate and Reference Voltage MAX LTC2413 22 RESOLUTION = LOG (V /INL ) 2 REF MAX ...
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... When the internal oscillator is used, the shape of the LTC2413 input bandwidth is shown in Figure 36. When an external oscillator of frequency f is used, the shape of the LTC2413 input bandwidth can be derived from Figure 36, in which the horizontal axis is scaled by f /139800. ...
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... APPLICATIO S I FOR ATIO Normal Mode Rejection and Antialiasing One of the advantages delta-sigma ADCs offer over con- ventional ADCs is on-chip digital filtering. Combined with a large oversampling ratio, the LTC2413 significantly simplifies antialiasing filter requirements. 4 The sinc digital filter provides greater than 120dB normal ...
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... As a result of these remarkable normal mode specifica- tions, minimal (if any) antialias filtering is required in front of the LTC2413. If passive RC components are placed in front of the LTC2413, the input dynamic current should be considered (see Input Current section). In cases where large effective RC time constants are used, an external buffer amplifier may be required to minimize the effects of dynamic input current ...
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... It is clear that the LTC2413 rejection performance is maintained with no compromises in this extreme situation. When operating with large input signal levels, the user must observe that such signals do not violate the device’ ...
Page 36
... Another option is the use of a reference within the 5V input range of the LTC2413 and developing excitation via fixed gain, or LTC1043 based voltage multiplication, along with remote feedback in the excitation amplifiers, as shown in Figures 48 and 50 ...
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... For single variable element bridges, the nonlinearity of the half bridge output can be eliminated completely; if the refer- ence arm of the bridge is used as the reference to the ADC, as shown in Figure 46. The LTC2413 can accept inputs up to 1/2 V REF least 2x the highest value of the variable resistor. ...
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... U1B REF 0 – U2A REF SDO – + REF SCK LTC2413 6 – – IN U2B F O GND 10, 15, 16 2413 F44 sn2413 2413fs ...
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... LTC2413, via an inexpensive multiplexer such as the 74HC4052. Figure 49 shows the use of an LTC2413 with a differential multiplexer. This is an inexpensive multiplexer that will contribute some error due to leakage if used directly with the output from the bridge resistors are inserted as a protection mechanism from overvoltage ...
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... RTD 6 – IN GND 10, 15, 16 2413 F46 Figure 46. Remote Half Bridge Interface 5V R2 10k + 0. 10k LTC1050 10k – REF 560 4 – REF LTC2413 10k 10k 6 – IN GND 10, 15, 16 2413 F47 sn2413 2413fs ...
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... F FILM 12 200 14 –10V LTC2413 10V LT1236 0 0 LTC2413 3 + REF 4 – REF – IN GND 10, 15 *FLYING CAPACITORS ARE 1 F FILM (MKP OR EQUIVALENT SEE LTC1043 DATA SHEET FOR DETAILS ON UNUSED HALF OF U1 ...
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... APPLICATIO S I FOR ATIO TO OTHER DEVICES Figure 49. Use a Differential Multiplexer to Expand Channel Capability 74HC4052 REF 4 – REF LTC2413 – IN GND 10, 15 2413 F49 sn2413 2413fs ...
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... However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights Package 16-Lead Plastic SSOP (Narrow .150 Inch) (Reference LTC DWG # 05-08-1641) TOP VIEW GN PACKAGE LTC2413 16 GND 15 GND ...
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... Output Rate at 60Hz Rejection, Pin Compatible with LTC2410 ADC in SO-8 1.2ppm Noise, 8ppm INL, Pin Compatible with LTC2400 ADC 1.2ppm Noise, 8ppm INL, Pin Compatible with LTC2404/LTC2408 5V LT1236 0 LTC2413 3 + REF 4 – REF – IN RN1 GND 10k ...