LTC1098 LINER [Linear Technology], LTC1098 Datasheet
LTC1098
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LTC1098 Summary of contents
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... These 8-bit, switched-capacitor, successive approximation ADCs include sample-and-hold. The LTC1096/LTC1096L have a single differential analog input. The LTC1098/LTC1098L offer a software selectable 2-channel MUX. On-chip serial ports allow efficient data transfer to a wide range of microprocessors and microcontrollers over three wires ...
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... IN t CLK High Time WHCLK (Notes 1 and 2) Operating Temperature LTC1096AC/LTC1096C/LTC1096LC/ LTC1098AC/LTC1098C/LTC1098LC ....... 0.3V CC LTC1096AI/LTC1096I/LTC1096LI/ LTC1098AI/LTC1098I/LTC1098LI ..... – 0.3V CC Lead Temperature (Soldering, 10 sec.)................ 300 (Notes 3) ORDER PART NUMBER CS/ 1 SHUTDOWN CH0 2 LTC1096ACN8 CH1 3 LTC1096ACS8 GND ...
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... Setup Time CS Before First CLK (See Operating Sequence) suCS t Wake-Up Time CS Before First CLK After First CLK WAKEUP (See Figure 1, LTC1096L Operating Sequence) Wake-Up Time CS Before MSBF Bit CLK (See Figure 2, LTC1098L Operating Sequence) t Setup Time, D Stable Before CLK suDI IN t CLK High Time ...
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... LTC1096A/LTC1098A CONDITIONS MIN 8 (Notes 2.500V REF (Notes (Notes 8, 9) CONDITIONS (Note 2.5V REF (Notes 6, 7) 2.65V V 4.0V CC (Note 8) LTC1096/LTC1098 TYP MAX MIN TYP MAX 8 0.5 0.5 0.5 0.5 0.5 1.0 0.5 1.0 – 0.05V 0.05V CC – 0.05V 0.05V CC – 0.05V to 6V 1.0 1.0 LTC1096/LTC1098 ...
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... CYC CLK 250kHz CYC CLK LTC1096, t 200 s, f 50kHz CYC CLK LTC1096 250kHz CYC CLK LTC1098, t 200 s, f 50kHz CYC CLK LTC1098 250kHz CYC CLK LTC1096/LTC1096L LTC1098/LTC1098L MIN TYP MAX UNITS 2.0 V 0.8 V 2.5 A – 2.5 A 4.5 4.74 V 2.4 4.72 V ...
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... CYC CLK LTC1096L 250kHz CYC CLK LTC1098L, t 200 s, f 50kHz CYC CLK LTC1098L 250kHz CYC CLK CONDITIONS See Operating Sequence See Operating Sequence See Test Circuits See Test Circuits See Test Circuits C = 100pF LOAD ...
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... Note 7: The supply voltage range for the LTC1096L/LTC1098L is from 2.65V to 4V. The supply voltage range for the LTC1096 is from 3V to 9V, but the supply voltage range for the LTC1098 is only from 3V to 6V. Note 8: Channel leakage current is measured after the channel selection. Note 9: These specifications are either correlated from 5V specifications or guaranteed by design ...
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... LTC1096/LTC1096L LTC1098/LTC1098L W U TYPICAL PERFOR A Supply Current vs Clock Rate for Active and Shutdown Modes 250 200 150 100 50 10 0.002 100 1000 1 FREQUENCY (kHz) LTC1096/98 • TPC01 Change in Offset vs Reference Voltage LTC1096 0. 25°C ...
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... REF 31.25kHz SMPL FREQUENCY (kHz) LTC1096/98 • TPC17 LTC1096/LTC1096L LTC1098/LTC1098L Digital Input Logic Threshold vs Supply Voltage SUPPLY VOLTAGE, V (V) CC LTC1096/98 • TPC12 Input Channel Leakage Current ...
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... IN (CH1) 10 LTC1098/LTC1098L CS/SHDN (Pin 1): Chip Select Input. A logic low on this input enables the LTC1098/LTC1098L. A logic high on this input disables the LTC1098/LTC1098L and disconnects the power to the LTC1098/LTC1098L. CH0 (Pin 2): Analog Input. This input must be free of noise with respect to GND. CH1 (Pin 3): Analog Input. This input must be free of noise with respect to GND ...
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... NOTE 1: WAVEFORM 1 IS FOR AN OUTPUT WITH INTERNAL CONDITIONS SUCH THAT THE OUTPUT IS HIGH UNLESS DISABLED BY THE OUTPUT CONTROL. NOTE 2: WAVEFORM 2 IS FOR AN OUTPUT WITH INTERNAL CONDITIONS SUCH THAT THE OUTPUT IS LOW UNLESS DISABLED BY THE OUTPUT CONTROL. LTC1096/LTC1096L LTC1098/LTC1098L Load Circuit for and t dDO ...
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... It can measure signals floating common mode voltage and can operate with reduced spans down to 250mV. Reducing the span allows it to achieve 1mV resolution. The LTC1098(L) has a 2-channel input multiplexer and can convert either channel with respect to ground or the difference between the two ...
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... COMPLETING THE DATA TRANSFER, IF FURTHER CLOCKS ARE APPLIED WITH CS LOW, THE ADC WILL OUTPUT ZEROS INDEFINITELY CLK D OUT CS CLK D OUT than 100kHz, Figure 1 shows the relationship between the wake-up time and setup time. The wake-up time is inherently provided for the LTC1098(L) with setup time = 1 s (see Figure 2). t CYC NULL BIT ...
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... IN OUT Data transfer is initiated by a falling chip select (CS) signal. After CS falls the LTC1098(L) looks for a start bit. After the start bit is received, the 3-bit input word is shifted into the D input which configures the LTC1098(L) and starts the IN conversion. After one null bit, the result of the conversion ...
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... The processor + – pin connected to this data line should be configurable as – + either an input or an output. The LTC1098(L) will take LTC1096/8 • AI03 control of the data line and drive it low on the 4th falling LTC1096/LTC1096L LTC1098/LTC1098L line in MSB-first format. Logical zeros will be line ...
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... Intel 8051 MPU. ACHIEVING MICROPOWER PERFORMANCE With typical operating currents and automatic shutdown between conversions, the LTC1096/LTC1098 achieves extremely low power consumption over a wide range of sample rates (see Figure 4). In systems that convert continuously, the LTC1096/LTC1098 will draw its 1000 T = 25° ...
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... LTC1098L. These pin compatible devices offer specified performance to 2.65V supply. MIN OPERATING ON OTHER THAN 5V SUPPLIES The LTC1096 operates from supplies and the LTC1098 operates from supplies. To operate the LTC1096/LTC1098 on other than 5V supplies, a few things must be kept in mind Wake-Up Time wake-up time must be provided for the ADCs to convert correctly supply ...
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... The S&H of the LTC1096(L) acquires input signals from P1.2 “+” input relative to “–” input during the t 50k Figure 1). However, the S&H of the LTC1098(L) can sample input signals in the single-ended mode or in the LTC1096/98 • F06 differential inputs during the t ...
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... The input capacitor of the LTC1096(L) is switched onto “+” input during the wake-up time (see Figure 1) and samples the input signal within that time. However, the input capacitor of the LTC1098(L) is switched onto “+” input during the sample phase (t SMPL sample phase is 1.5 CLK cycles before conversion starts. ...
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... In this IN Figure 10. Reference Input Equivalent Circuit Reduced Reference Operation The minimum reference voltage of the LTC1098 is limited to 3V because the V tied together. However, the LTC1096 can operate with reference voltages below 1V. The effective resolution of the LTC1096 can be increased by reducing the input span of the converter. The LTC1096 LTC1096/8 • ...
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... DC to 15.625kHz which is 1/2 the 31.25kHz sam- pling rate will add REF IN REF Figure 11. This Clean FFT of an 11.8kHz Input Shows Remarkable Performance for an ADC That Draws Only 100 A When Sampling at the 31.25kHz Rate LTC1096/LTC1096L LTC1098/LTC1098L 31.25kHz SAMPLE – 11.8kHz IN –20 –30 –40 – ...
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... Table 1 MPU without a dedicated serial port is used, then three or four of the MPU’s parallel port lines can be programmed to form the serial link to the LTC1096(L)/LTC1098(L). Included here is one serial interface example and one example showing a parallel port programmed to form the serial interface ...
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... LTC1098 INPUTS OUT D from LTC1098(L) Stored in MC68HC05C4 OUT LOCATION LOCATION Data Exchange Between LTC1098(L) and MC68HC05C4 START BIT BYTE 1 SGL/ ODD MSBF X X DIFF SIGN START SGL/ ODD/ MSBF DIFF SIGN ...
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... fourth port line. This works very well. However, we will demonstrate here an interface with the D of the LTC1098(L) tied together as described in the SERIAL INTERFACE section. This saves one wire. The 8051 first sends the start bit and MUX address to the LTC1098(L) over the data line connected to P1 ...
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... LOAD LM134 678 LTC1096/8 • F13 13.5k 0.01 F pin REF Figure 15. The LTC1096’s High Impedance Input Connects Directly to This Temperature Sensor, Eliminating Signal Conditioning Circuitry in This Thermometer LTC1096/LTC1096L LTC1098/LTC1098L LSB LSB DATA NULL MSB (B0) (B1) (B7) BIT VERTICAL: 5V/DIV HORIZONTAL: 10 s/DIV ) ...
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... LTC1096/LTC1096L LTC1098/LTC1098L TYPICAL PPLICATI Remote or Isolated Systems Figure 16 shows a floating system that sends data to a grounded host system. The floating circuitry is isolated by two optoisolators and powered by a simple capacitor diode charge pump. The system has very low power requirements because the LTC1096 shuts down between ...
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... TYP 0.016 – 0.050 0.014 – 0.019 0.406 – 1.270 (0.355 – 0.483) LTC1096/LTC1096L LTC1098/LTC1098L 0.130 0.005 (3.302 0.127) 0.125 0.015 (3.175) MIN (0.380) MIN ...
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... O TYPICAL A PPLICATI A/D Conversion for 3V Systems The LTC1096/LTC1098 are ideal for 3V systems. Figure 17 shows battery current monitor that draws only 70 A from the battery it monitors. The battery current is sensed with the 0.02 resistor and amplified by the LT1178. The LTC1096 digitizes the amplifier output and sends it to the microprocessor in serial format ...