ltc1196-2bcs8-trpbf Linear Technology Corporation, ltc1196-2bcs8-trpbf Datasheet
ltc1196-2bcs8-trpbf
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ltc1196-2bcs8-trpbf Summary of contents
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... These ADCs can be used in ratiometric applications or with external references. The high impedance analog in- puts 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 specifi ed with total unadjusted error of ± ...
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... For more information on tape and reel specifi cations, go to: 2 (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°C to 70°C + 0.3V Storage Temperature Range .................. –65°C to 150°C CC Lead Temperature (Soldering, 10 sec) ................ 300°C LTC1198 ...
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... LTC1198 16 2 LTC1198 20 LTC1198 40% CLK CLK(MAX 40% CLK CLK(MAX) 25 LTC1196 11 LTC1198 15 CONDITIONS MIN (Note LTC1196 5.000V REF LTC1198 5.000V CC LTC1196 l (Note 5) CONDITIONS V = 5.25V 4.75V 4.75V 10μ 4.75V 360μ ...
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... 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 CC DYNAMIC ACCURACY otherwise specifi cations are 25° unless otherwise noted. SYMBOL PARAMETER S/( Signal-to-Noise Plus Distortion ...
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... LTC1198 40 LTC1198 40% CLK CLK(MAX 40% CLK CLK(MAX) 50 LTC1196 11 LTC1198 15 CONDITIONS MIN (Note LTC1196 2.5.000V REF LTC1198 2.700V CC LTC1196 l (Note 5) = 25° CONDITIONS 2.7V 10μ 2.7V 360μA ...
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... T SYMBOL PARAMETER I Output Source Current SOURCE I Output Sink Current SINK I Reference Current, LTC1196 REF I Supply Current CC DYNAMIC ACCURACY otherwise specifi cations are 25° unless otherwise noted. ...
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... SUPPLY VOLTAGE (V) Offset vs Reference Voltage 1 25° 1.4 f CLK 1.2 1.0 0.8 0.6 0.4 0.2 0 125 0.5 1.0 1.5 2.5 3.0 3.5 2.0 4.0 REFERENCE VOLTAGE (V) LTC1196/LTC1198 Supply Current vs Sample Rate 10 LT1196 LT1196 V = 2.7V CC LT1198 0.1 CC LT1198 V 0.01 0.001 5.5 6.0 100 1k 10k SAMPLE RATE (Hz) 1196/98 G02 Offset vs Supply Voltage 0 25° REF ...
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... LTC1196/LTC1198 TYPICAL PERFORMANCE CHARACTERISTICS Linearity Error vs Reference Voltage 1 25° 12MHz CLK 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 1.5 2.5 3.0 3.5 4.5 0.5 1.0 2.0 4.0 REFERENCE VOLTAGE (V) 1196/98 G07 Gain vs Supply Voltage 0 25° 3MHz CLK REF CC 0.3 0.2 0.1 0 –0.1 –0.2 –0.3 –0.4 –0.5 4.5 2.5 3.0 3.5 4.0 5.0 5.5 SUPPLY VOLTAGE (V) 1196/98 G10 Minimum Clock Rate for ...
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... CODE 1196/98 G20 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 2. ...
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... LTC1196/LTC1198 TYPICAL PERFORMANCE CHARACTERISTICS 4096 Point FFT Plot – 29kHz 882kHz SMPL –20 –30 –40 –50 –60 –70 –80 –90 –100 0 100 200 300 400 FREQUENCY (kHz) 1196/98 G25 Power Supply Feedthrough vs Ripple Frequency 25° ...
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... INPUT FREQUENCY (Hz) PIN FUNCTIONS 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 BLOCK DIAGRAM + IN (CH0) – IN (CH1) PIN NAMES IN PARENTHESES REFER TO THE LTC1198 TEST CIRCUITS On and Off Channel Leakage Current OFF A • • • • POLARITY Voltage Waveform for D Rise and Fall Times, t OUT D OUT (CS/SHUTDOWN ...
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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. Voltage Waveforms for Voltage Waveforms for LTC1196/LTC1198 Voltage Waveforms for t dis CS t dis 1196/98 TC07 ...
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... 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 fl oating common mode voltage and can operate with reduced spans below 1V ...
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... 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 ad- ditional input used to select the 2-channel MUX IN confi ...
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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 IN supply 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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... LTC1196/LTC1198. Minimizing R input settling time large “+” input source resistance must be used, the sample time can be increased by allow- ing more time between conversions for the LTC1196 or by using a slower CLK frequency for the LTC1198. LTC1196/LTC1198 H ...
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... IN Figure 8. Analog Input Equivalent Circuit 20 REFERENCE INPUT The voltage on the reference input of the LTC1196 defi nes the voltage span of the A/D converter. The reference input has transient capacitive switching currents which are due to the switched-capacitor conversion technique (see Figure 9). During each bit test of the conversion (every CLK cycle), a capacitive current spike will be generated on the reference – ...
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... APPLICATIONS INFORMATION 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 fi xed voltage) becomes a larger fraction of an LSB as the size of the LSB is reduced. The typical curve of Unadjusted Offset ...
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... APPLICATIONS INFORMATION where N is the effective number of bits of resolution and S/( expressed in dB. At the maximum sampling 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 fl oor remains low ...
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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 TYPICAL APPLICATIONS 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 for speed of transfer and minimum processor supervision, can complete a conversion and shift the data in 4μ ...
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... All clocking and CS functions are performed by the hardware. 1196/98 F17 LSB B15 (B0) 0 Figure 18. D Circuit in Figure 15 LTC1196/LTC1198 word is then put in the transmit register S/D ...
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... LTC1196/LTC1198 TYPICAL APPLICATIONS 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-justifi 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 .016 – .050 .014 – .019 (0.406 – 1.270) (0.355 – 0.483) TYP INCHES (MILLIMETERS) LTC1196/LTC1198 .189 – .197 (4.801 – 5.004) NOTE .150 – .157 (3.810 – 3.988) ...
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... LTC1196/LTC1198 RELATED PARTS PART NUMBER DESCRIPTION ADCs LTC1402 12-Bit, 2.2Msps Serial ADC LTC1403/LTC1403A 12-/14-Bit, 2.8Msps Serial ADCs LTC1403-1/LTC1403A-1 12-/14-Bit, 2.8Msps Serial ADCs LTC1405 12-Bit, 5Msps Parallel ADC LTC1407/LTC1407A 12-/14-Bit, 3Msps Simultaneous Sampling ADCs LTC1407-1/LTC1407A-1 12-/14-Bit, 3Msps Simultaneous Sampling ADCs LTC1411 14-Bit, 2 ...