LTC1096 Linear Technology, LTC1096 Datasheet
LTC1096
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LTC1096 Summary of contents
Page 1
... They are packaged in 8-pin SO packages and have both 3V (L) and 5V versions. 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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... 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 LTC1096 Operating Sequence) Wake-Up Time CS Before MSBF Bit CLK (See Figure 2 LTC1098 Operating Sequence) t Setup Time, D Stable Before CLK suDI ...
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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 ...
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... Total Unadjusted Error (Notes 5) Analog Input Range REF Input Range (Note 6) Analog Input Leakage Current 4 LTC1096A/LTC1098A CONDITIONS MIN 8 (Note 5.000V REF (Notes < V 9V, LTC1096 CC (Note 8) LTC1096A/LTC1098A CONDITIONS MIN 8 (Notes 2.500V REF (Notes (Notes 8, 9) CONDITIONS (Note ...
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... 200 s, f 50kHz 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 ...
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... CYC CLK 250kHz CYC CLK LTC1096L, t 200 s, f 50kHz 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 ...
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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. ...
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... SAMPLE FREQUENCY, f Change in Linearity vs Reference Voltage LTC1096 0.50 0.25 0 –0.25 –O. REFERENCE VOLTAGE (V) Change in Gain vs Reference Voltage LTC1096 0.50 0.25 0 –0.25 –O. VOLTAGE REFERENCE (V) 10 100 (kHz) SMPL LTC1096/98 • TPC03 T = 25° ...
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... 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 vs Temperature 1000 REF 100 10 ON CHANNEL 1 OFF CHANNEL 0.1 0.01 100 –60 –40 –20 0 ...
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... LTC1098/LTC1098L CTIO S LTC1096/LTC1096L CS/SHDN (Pin 1): Chip Select Input. A logic low on this input enables the LTC1096/LTC1096L. A logic high on this input disables the LTC1096/LTC1096L and disconnects the power to the LTC1096/LTC1096L (Pin 2): Analog Input. This input must be free of noise with respect to GND. ...
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... 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 TEST POINT OUT 100pF LTC1096/98 • TC02 Rise and Fall Times, t OUT Voltage Waveforms for t dis 2.0V t dis , ...
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... They are packaged in 8-pin SO packages. The LTC1096L/LTC1098L operate on a single supply ranging from 2.65V to 4V. The LTC1096 operates on a single supply ranging from while the LTC1098 operates from supplies. ...
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... CS falling to the first falling clock (CLK) after the first rising CLK for the LTC1096(L) and from CS falling to the MSBF bit CLK falling for the LTC1098(L) (see Operating Sequence). If the LTC1096(L)/ LTC1098(L) are running with clock frequency less than or equal to 100kHz, the wake-up time is inherently provided ...
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... D CS should be brought high. This resets the LTC1098(L) in preparation for the next data exchange. The LTC1096(L) does not require a configuration input word and has shown in the LTC1096(L) operating sequence. After CS falls, the first CLK pulse enables D POWER DOWN Hi-Z ...
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... PPLICATI S I FOR ATIO the A/D conversion result is output on the D Bringing CS high resets the LTC1096(L) for the next data exchange. Input Data Word The LTC1096(L) requires no D word permanently IN configured to have a single differential input. The conver- sion result, in which output on the D sequence, followed by LSB sequence providing easy inter- face to MSB- or LSB-first serial ports ...
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... During cConversions, Drops to Zero in Shutdown Shutdown Figures 1 and 2 show the operating sequence of the 100 LTC1096/LTC1098. The converter draws power when the (kHz) CS pin is low and powers itself down when that pin is high. LTC1096/98 • TPC03 If the CS pin is not taken to ground when it is low and not ...
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... MPU (see typical curve of Digital Input Logic Threshold vs Supply Voltage). With the LTC1096 operating supply, the output of D may go between 0V and 9V. The 9V output may damage the MPU running off a 5V supply. The way to get around ...
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... GND V 6V REF LTC1096 Figure 6. Interfacing a 9V Powered LTC1096 System BOARD LAYOUT CONSIDERATIONS Grounding and Bypassing The LTC1096(L)/LTC1098(L) should be used with an ana- log ground plane and single point grounding techniques. The GND pin should be tied directly to the ground plane. ...
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... Input Settling 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 “ ...
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... Noise 3. Conversion speed (CLK frequency) Offset with Reduced V The offset of the LTC1096 has a larger effect on the output code when the ADC is operated with reduced reference voltage. The offset (which is typically a fixed voltage) becomes a larger fraction of an LSB as the size of the LSB is reduced ...
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... CLK frequency when low values of V are used. REF Input Divider use an input divider on the reference input of the LTC1096 as long as the reference input can be made For example, settle within the bit time at which the clock is running. OS When using a larger value resistor divider on the reference input the “ ...
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... A/D and is directly related to the S/( the equation: ENOB = [S/( –1.76]/6.02 where S/( expressed in dB. At the maximum sampling rate of 33kHz the LTC1096 maintains 7.5 ENOBs or better to 40kHz. Above 40kHz the ENOBs gradually decline, as shown in Figure 12, due to increasing second harmonic distortion. The noise floor remains approxi- mately 70dB ...
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... 2ND TRANSFER LTC1096/8 • TA03 MNEMONIC COMMENTS BCLRn Bit 0 Port C goes low (CS goes low) LDA Load LTC1098(L) D word into Acc. IN STA Load LTC1098(L) D word into SPI from Acc. IN Transfer begins. TST Test status of SPIF ...
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... Rotate data bit into Acc. P1.3 CLK goes high P1.3 CLK goes low R4, LOOP Next bit R2, A Store MSBs in R2 P1.4 CS goes high from LTC1098(L) Stored in 8051 RAM OUT MSB LSB LTC1096/8 • TA07 BACK TO 8051 P1.2 LTC1096/8 • TA08 ...
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... TO OSCILLOSCOPE Figure 13. “Quick Look” Circuit for the LTC1096 Figure 15 shows a temperature measurement system. The LTC1096 is connected directly to the low cost silicon temperature sensor. The voltage applied to the V adjusts the full scale of the A/D to the output range of the sensor. The zero point of the converter is matched to the zero output voltage of the sensor by the voltage on the LTC1096’ ...
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... 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 0.001 F 2kV 5MHz ...
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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 ...