LTC1196-2AC LINER [Linear Technology], LTC1196-2AC Datasheet
LTC1196-2AC
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LTC1196-2AC Summary of contents
Page 1
... These ADCs can be used in ratiometric applications or with external references. The high impedance analog inputs and the ability to operate with reduced spans below 1V full scale (LTC1196) allow direct connection to signal sources in many applications, eliminating the need for gain stages. The A grade devices are specified with total unadjusted error of 1/2LSB maximum over temperature ...
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... After CLK hDI (Notes 1, 2) Operating Temperature Range LTC1196-1AC, LTC1198-1AC, LTC1196-1BC, + 0.3V LTC1198-1BC, LTC1196-2AC, LTC1198-2AC, CC LTC1196-2BC, LTC1198-2BC................ 0.3V Storage Temperature Range ................ – 150 C CC Lead Temperature (Soldering, 10 sec)................ 300 ORDER PART NUMBER* LTC1196-1ACS8 CS/ 1 SHUTDOWN ...
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... Low Level Input Current IL V High Level Output Voltage OH V Low Level Output Voltage OL I Hi-Z Output Leakage OZ I Output Source Current SOURCE I Output Sink Current SINK I Reference Current, LTC1196 REF I Supply Current CONDITIONS LTC1198 CLK CLK(MAX CLK CLK(MAX) ...
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... LOAD C = 20pF LOAD C = 20pF 30 LOAD C = 20pF LOAD C = 20pF LOAD Analog Input On Channel Analog Input Off Channel Digital Input LTC1196-1 LTC1198-1 CONDITIONS MIN TYP 0.01 0.01 LTC1196 12 LTC1198 16 2 LTC1198 MAX MIN TYP MAX 47/45 49/47 55/ LTC1196-2 LTC1198-2 MAX MIN TYP MAX ...
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... Low Level Input Current IL V High Level Output Voltage OH V Low Level Output Voltage OL I Hi-Z Output Leakage OZ I Output Source Current SOURCE I Output Sink Current SINK I Reference Current, LTC1196 REF I Supply Current CONDITIONS LTC1198 LTC1198 CLK CLK(MAX CLK ...
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... Note 5: Channel leakage current is measured after the channel selection. LTC1196 LTC1198 MIN TYP MAX MIN TYP MAX 47/45 47/45 49/47 49/47 53/46 53/ 0.5 0.5 LTC1196-1 LTC1196-2 LTC1198-1 LTC1198-2 MIN TYP MAX MIN TYP MAX 1.58 2.13 1.85 2.84 450 333 383 250 337 250 287 187 ...
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... Linearity Error vs Supply Voltage 0 25° REF CC 0 3MHz CLK 0.2 0.1 0 –0.1 –0.2 –0.3 –0.4 –0.5 2.5 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (V) LTC1196/LTC1198 Supply Current vs Sample Rate 10 LT1196 LT1196 V = 2.7V CC LT1198 0.1 CC LT1198 V CC 0.01 0.001 6.0 100 1k 10k SAMPLE RATE (Hz) Offset vs Supply Voltage 0 25°C A 0.4 V ...
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... LTC1196/LTC1198 W U TYPICAL PERFOR A Gain vs Supply Voltage 0 25°C 0 3MHz CLK 0 REF CC 0.2 0.1 0 –0.1 –0.2 –0.3 –0.4 –0.5 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 SUPPLY VOLTAGE (V) 1196/98 G10 Minimum Clock Rate for 0.1LSB* Error 100 REF –55 –35 – ...
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... Effective Bits and S/( Input Frequency 2.7V CC REF 383kHz (LTC1196) SMPL f = 287kHz (LTC1198) SMPL REF f = 1MHz (LTC1196) SMPL 750kHz (LTC1198) SMPL 25° 10k 100k INPUT FREQUENCY (Hz) FFT Output of 455kHz AM Signal Digitized at 1MSPS 0 V ...
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... LTC1196/LTC1198 W U TYPICAL PERFOR A Power Supply Feedthrough vs Ripple Frequency 25°C A – 20mV) CC RIPPLE f = 12MHz CLK –20 –30 –40 –50 –60 –70 1k 10k 100k 1M RIPPLE FREQUENCY (Hz) 1196/98 G28 Intermodulation Distortion at 2. 2.7V CC – 100kHz f2 = 110kHz – 420kHz SMPL –30 –40 – ...
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... CTIO S LTC1196 CS (Pin 1): Chip Select Input. A logic low on this input enables the LTC1196. A logic high on this input disables the LTC1196 (Pin 2): Analog Input. This input must be free of noise with respect to GND. – IN (Pin 3): Analog Input. This input must be free of noise with respect to GND ...
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... LTC1196/LTC1198 TEST CIRCUITS On and Off Channel Leakage Current OFF A • • • • POLARITY Voltage Waveform for D Rise and Fall Times, t OUT D OUT t r Load Circuit for t dis TEST POINT OUT t 20pF 12 ON CHANNEL OFF CHANNEL 1196/98 TC01 ...
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... TEST CIRCUITS LTC1196 CS CLK D OUT LTC1198 START CLK 1 D OUT Voltage Waveforms for Voltage Waveforms for LTC1196/LTC1198 4 B7 1196/98 TC07 1196/98 TC08 13 ...
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... Block Diagram). The on-chip sample-and-holds have full-accuracy input bandwidths of 1MHz. Although they share the same basic design, the LTC1196 and LTC1198 differ in some respects. The LTC1196 has a differential input and has an external reference input pin. It can measure signals floating common-mode voltage and can operate with reduced spans below 1V ...
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... LTC1196 Operating Sequence. After CS falls, the first CLK pulse enables D . After two null bits, the A/D OUT conversion result is output on the D high resets the LTC1196 for the next data exchange. The LTC1198 can transfer data with wires. The additional input used to select the 2-channel MUX IN configuration ...
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... The LTC1198 can reduce power even further because it shuts down whenever it is not converting. Figure 5 shows the supply current versus sample rate for the LTC1196 and LTC1198 on 3V and 5V. To achieve such a low power consumption, especially for the LTC1198, several things must be taken into consideration. ...
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... SAMPLE RATE (Hz) Figure 5. Supply Current vs Sample Rate for LTC1196/ LTC1198 Operating on 5V and 2.7V Supplies When the CS pin is high (= supply voltage), the LTC1198 is in shutdown mode and draws only leakage current. The status of the D and CLK input has no effect on the supply IN current during this time ...
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... OUT GND V 3V REF Figure 6. Interfacing a 3V Powered LTC1196 System BOARD LAYOUT CONSIDERATIONS Grounding and Bypassing The LTC1196/LTC1198 are easy to use if some care is taken. They should be used with an analog ground plane and single-point grounding techniques. The GND pin should be tied directly to the ground plane. ...
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... Figure 7. LTC1198 “+” and “–” Input Settling Windows “+” Input Settling The input capacitor of the LTC1196 is switched onto “+” input at the end of the conversion and samples the input signal until the conversion begins (see Figure 1). The input capacitor of the LTC1198 is switched onto “ ...
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... However, the LTC1196 can operate with reference voltages below 1V. The effective resolution of the LTC1196 can be increased by reducing the input span of the converter. The LTC1196 exhibits good linearity and gain over a wide range of reference voltages (see typical curves of Linearity and Full- Scale Error vs Reference Voltage) ...
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... S I FOR ATIO Offset with Reduced V REF The offset of the LTC1196 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. The typical curve of Unadjusted Offset Error vs ...
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... LTC1196/LTC1198 PPLICATI S I FOR ATIO rate of 1.2MHz with a 5V supply the LTC1196 maintains above 7.5 ENOBs at 400kHz input frequency. Above 500kHz the ENOBs gradually decline, as shown in Figure 11, due to increasing second harmonic distortion. The noise floor remains low 2.7V CC REF ...
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... Figure 12. The circuit works as follows: bringing ENA high makes the CS output high and the EN input low to reset the LTC1196 and disable the shift register. Bringing ENA low, the CS output DATA ...
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... LTC1196/LTC1198 U O TYPICAL A PPLICATI DATA CLK 140 210 280 Interfacing the LTC1198 to the TMS320C25 DSP Figure 15 illustrates the interface between the LTC1198 8-bit data acquisition system and the TMS320C25 digital signal processor (DSP). The interface, which is optimized ...
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... All clocking and CS functions are performed by the hardware. B15 LSB 0 (B0) 1196/98 F17 Figure 18. D Circuit in Figure 15 LTC1196/LTC1198 word is loaded into the ACC and IN word configures the LTC1198 for CH0 with word is then put in the transmit ...
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... LTC1196/LTC1198 O U TYPICAL A PPLICATI Once RINT is generated the code begins execution at the label RINT. This code stores the D LTC1198 in the ACC and then stores it in location 200 hex. The data appears in location 200 hex right-justified as shown in Figure 19. The code is set up to continually loop this point the code jumps to label TXRX and repeats from here ...
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... TYP 0.014 – 0.019 (0.355 – 0.483) LTC1196/LTC1198 0.150 – 0.157 (3.810 – 3.988 0.004 – 0.010 (0.101 – 0.254) ...
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... LTC1196/LTC1198 NORTHEAST REGION Linear Technology Corporation One Oxford Valley 2300 E. Lincoln Hwy.,Suite 306 Langhorne, PA 19047 Phone: (215) 757-8578 FAX: (215) 757-5631 Linear Technology Corporation 266 Lowell St., Suite B-8 Wilmington, MA 01887 Phone: (508) 658-3881 FAX: (508) 658-2701 FRANCE Linear Technology S.A.R.L. Immeuble "Le Quartz" ...