LTC1286 Linear Technology, LTC1286 Datasheet
LTC1286
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LTC1286 Summary of contents
Page 1
... They are packaged in 8-pin SO packages and operate supplies. These 12-bit, switched-capacitor, suc- cessive approximation ADCs include sample-and-holds. The LTC1286 has a single differential analog input. The LTC1298 offers 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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... CS Low Time During Data Transfer WLCS 2 RATINGS (Notes 1 and 2) Power Dissipation .............................................. 500mW Operating Temperature Range + 0.3V LTC1286C/LTC1298C............................. LTC1286I/LTC1298I ........................... – 0.3V Storage Temperature Range ................. – 150 C CC Lead Temperature (Soldering, 10 sec.)................ 300 ORDER PART NUMBER V 1 REF ...
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... CONVERTER AND MULTIPLEXER CHARACTERISTICS PARAMETER Resolution (No Missing Codes) Integral Linearity Error Differential Linearity Error Offset Error Gain Error Analog Input Range REF Input Range (LTC1286) (Notes 7, 8, and 9) Analog Input Leakage Current (Note 10) U DIGITAL AND DC ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER V High Level Input Voltage ...
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... Note 8: The supply voltage range for the LTC1286 is from 4.5V to 9V, but the supply voltage range for the LTC1298 is only from 4.5V to 5.5V. Note 9: Recommended operating conditions Note 10: Channel leakage current is measured after the channel selection ...
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... W U TYPICAL PERFORMANCE CHARACTERISTICS Reference Current vs Sample Rate (LTC1286) 100 T = 25° REF 200kHz CLK FREQUENCY (kHz) LT1286/98 G06 Change in Offset vs Temperature 0 -0 REF -2 200kHz CLK SMPL ...
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... LTC1286/LTC1298 W TYPICAL PERFORMANCE CHARACTERISTICS Spurious Free Dynamic Range vs Frequency 100 25° REF 12.5kHz SMPL 0 1k 10k 100k 1M INPUT FREQUENCY (Hz) LTC 1286/98 G27 4096 Point FFT Plot 25° REF – 5kHz ...
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... Negative Analog Input. GND (Pin 4): Analog Ground. GND should be tied directly to an analog ground plane. CS/SHDN (Pin 5): Chip Select Input. A logic low on this input enables the LTC1286. A logic high on this input disables and powers down the LTC1286. D (Pin 6): Digital Data Output. The A/D conversion OUT result is shifted out of this output ...
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... SERIAL PORT D OUT SAR PIN NAMES IN PARENTHESES REFER TO THE LTC1298 Rise and Fall Times, t OUT Load Circuit for t and t dis en TEST POINT V t WAVEFORM dis 3k D OUT t WAVEFORM 1 dis 100pF , LTC1286/98 • TC02 en LTC1286/98 • TC04 ...
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... Supply current drops linearly as the sample rate is reduced (see Supply Current vs Sample Rate). The ADCs automatically power down when not performing conversions, drawing only leakage current. They are packaged in 8-pin SO and DIP packages. The LTC1286 operates on a single supply from 4.5V to 9V, dis LTC1286 V IH ...
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... W U A/D conversion result is output on the D CS high resets the LTC1286 for the next data exchange. The LTC1298 first receives input data and then transmits back the A/D conversion result (half duplex). Because of the half duplex operation, D together allowing transmission over just 3 wires: CS, CLK and DATA (D Data transfer is initiated by a falling chip select (CS) signal ...
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... RESULT OUT t CYC DON'T CARE CONV t CYC DON'T CARE B0 CONV DATA LTC1286/LTC1298 D 2 OUT LTC1096/98 • AI01 POWER DOWN B10 B11 * t DATA POWER DOWN HI-Z + – HI-Z LTC1286/98 • F02 11 ...
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... MSBF bit is a logical zero, LSB first data will follow the normal MSB first data on the D Sequence) Transfer Curve The LTC1286/LTC1298 are permanently configured for unipolar only. The input span and code assignment for this conversion type are shown in the following figures. input on ...
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... Figure 4. Automatic Power Shutdown Between Conversions Allows Power Consumption to Drop with Sample Rate. Shutdown The LTC1286/LTC1298 are equipped with automatic shut- down features. They draw power when the CS pin is low and shut down completely when that pin is high. The bias circuit and comparator powers down and the reference ...
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... An alternative is to leave CS low after a conversion, clock data until D outputs zeros, and then stop the clock low. are made to meet IN DIFFERENTIAL INPUTS COMMON-MODE RANGE Figure 6. Interfacing a 9V Powered LTC1286 System OUT voltage to keep the (e.g. 8051) ...
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... SAMPLE-AND-HOLD Both the LTC1286 and the LTC1298 provide a built-in sample-and-hold (S&H) function to acquire signals. The S&H of the LTC1286 acquires input signals from “+” input relative to “–” input during the t However, the S&H of the LTC1298 can sample input signals in the single-ended mode or in the differential ...
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... Input Settling The input capacitor of the LTC1286 is switched onto “+” input during the t time (see Figure 1) and samples the SMPL input signal within that time. However, the input capacitor of the LTC1298 is switched onto “ ...
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... Noise 3. Conversion speed (CLK frequency) Offset with Reduced V The offset of the LTC1286 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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... LTC1286. Noise with Reduced V REF The total input referred noise of the LTC1286 can be reduced to approximately 400 V peak-to-peak using a ground plane, good bypassing, good layout techniques and minimizing noise on the reference inputs. This noise is insignificant with a 5V reference but will become a larger fraction of an LSB as the size of the LSB is reduced ...
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... The typical THD speci- fication in the Dynamic Accuracy table includes the 2nd through 5th harmonics. With a 7kHz input signal, the LTC1286/LTC1298 have typical THD of 80dB with V Intermodulation Distortion If the ADC input signal consists of more than one spectral component, the ADC transfer function nonlinearity can produce intermodulation distortion (IMD) in addition to THD ...
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... Table 1 MPU without a dedicated serial port is used, then the MPU's parallel port lines can be programmed to form the serial link to the LTC1286/LTC1298. Included here is one serial interface example and one example showing a parallel port programmed to form the serial interface. ...
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... LOAD DUMMY INTO ACC A FROM $52 $102A LOAD DUMMY DIN INTO SPI, START SCK $1029 CHECK SPI STATUS REG WAIT3 CHECK IF TRANSFER IS DONE $08,X#$01 DO GOES HIGH (CS GOES HIGH) $102A LOAD LTC1291 LSBs IN ACC $63 STORE LSBs IN $63 LOOP START NEXT CONVERSION LTC1286/98 AI06 21 ...
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... Rotate data bit into Acc. SETB P1.3 SCLK goes high CLR P1.3 SCLK goes low DJNZ R4, LOOP 3 Next bit MOV R4, #04 Load counter RRC A Rotate right into Acc. DJNZ R4, LOOP 4 Next Rotate MOV R3, A Store LSBs in R3 SETB P1.4 CS goes high LTC1286/98 TA02 ...
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... The 67 A from the 5V supply from the battery. The 12-bits of resolution of the LTC1286 are positioned over the desired range 16V. This is easily accomplished by using the ADC’s differential inputs. Tying the –input to the reference gives an ADC input span of V resistor divider then scales the input voltage for 8V to 16V ...
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... LTC1286/LTC1298 PACKAGE DESCRIPTION 0.300 – 0.320 (7.620 – 8.128) 0.065 (1.651) 0.009 – 0.015 TYP (0.229 – 0.381) +0.025 0.045 ± 0.015 0.325 –0.015 (1.143 ± 0.381) +0.635 8.255 –0.381 0.010 – 0.020 45 (0.254 – 0.508) 0.008 – 0.010 0° ...