LTC1196-1ACS8 Linear Technology, LTC1196-1ACS8 Datasheet
LTC1196-1ACS8
Specifications of LTC1196-1ACS8
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LTC1196-1ACS8 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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... GND 4 S8 PACKAGE 8-LEAD PLASTIC SO = 150°C, θ 175°C/W JMAX JA ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC1196-1ACS8#PBF LTC1196-1ACS8#TRPBF LTC1196-1BCS8#PBF LTC1196-1BCS8#TRPBF LTC1196-2ACS8#PBF LTC1196-2ACS8#TRPBF LTC1196-2BCS8#PBF LTC1196-2BCS8#TRPBF LTC1198-1ACS8#PBF LTC1198-1ACS8#TRPBF LTC1198-1BCS8#PBF LTC1198-1BCS8#TRPBF LTC1198-2ACS8#PBF LTC1198-2ACS8#TRPBF LTC1198-2BCS8#PBF LTC1198-2BCS8#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. ...
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... LTC1196 12 LTC1198 16 2 LTC1198 20 LTC1198 40% CLK CLK(MAX 40% CLK CLK(MAX) 25 LTC1196 11 LTC1198 15 LTC1196-1A/LTC1196-2A LTC1198-1A/LTC1198-2A 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 LTC1196/LTC1198 The l denotes the specifi cations which apply over ...
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... 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 CC DYNAMIC ACCURACY otherwise specifi cations are 25° unless otherwise noted. SYMBOL PARAMETER S/( Signal-to-Noise Plus Distortion THD Total Harmonic Distortion ...
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... CONDITIONS MIN 0.01 l 0.01 LTC1196 12 LTC1198 16 2 LTC1198 40 LTC1198 40% CLK CLK(MAX 40% CLK CLK(MAX) 50 LTC1196 11 LTC1198 15 LTC1196-1A/LTC1196-2A LTC1198-1A/LTC1198-2A CONDITIONS MIN (Note LTC1196 2.5.000V REF LTC1198 2.700V CC LTC1196 l (Note 5) = 25° CONDITIONS 2.7V 10μ 2.7V 360μ 2.7V 400μ HIGH LTC1196/LTC1198 ...
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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. SYMBOL PARAMETER ...
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... 1.4 f CLK 1.2 1.0 0.8 0.6 0.4 0.2 0 125 0.5 1.0 1.5 2.0 2.5 3.0 3.5 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 ...
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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 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 REFERENCE VOLTAGE (V) 1196/98 G07 Gain vs Supply Voltage 0 25° 3MHz ...
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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) 1196/98 G23 = 2. 120 100 140 1196/98 G18 192 224 256 ...
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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° 20mV) CC RIPPLE – 12MHz CLK –20 – ...
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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 REF BIAS AND SHUTDOWN CIRCUIT C SMPL – ...
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... 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. Voltage Waveforms for Voltage Waveforms for LTC1196/LTC1198 Voltage Waveforms for t dis CS t dis 1196/98 TC07 ...
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... It also automatically powers down when not performing conversion, drawing only leakage current. SERIAL INTERFACE The LTC1196/LTC1198 will interface via three or four wires to ASICs, PLDs, microprocessors, DSPs, or shift registers (see Operating Sequence in Figures 1 and 2). To run at their fastest conversion rates (600ns), they must be clocked at 14 ...
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... LTC1196 Operating Sequence in Figure 1. After CS falls, the fi rst CLK pulse enables D null bits, the A/D conversion result is output on the D line. Bringing CS HIGH resets the LTC1196 for the next data exchange. The LTC1198 can transfer data with three or four wires. ...
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... These two bits allow the ADC 2.5 clocks to acquire the input signal after the channel selection. A/D Conversion Result Both the LTC1196 and the LTC1198 have the A/D conver- sion result appear on the D line after two null bits (see OUT the operating sequences in Figures 1 and 2) ...
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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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... V CC DIFFERENTIAL INPUTS +IN CLK LTC1196 COMMON MODE RANGE –IN D OUT GND V 3V REF Figure 6. Interfacing a 3V Powered LTC1196 System CS CLK START OUT + INPUT – INPUT 18 BOARD LAYOUT CONSIDERATIONS Grounding and Bypassing The LTC1196/LTC1198 are easy to use if some care is OUT taken. They should be used with an analog ground plane and single-point grounding techniques ...
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... If a large “+” input source resistance must be used, the sample time can be increased by allowing more time between conversions for the LTC1196 or by using a slower CLK frequency for the LTC1198. “–” Input Settling At the end of the t ...
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... V 1. Offset 2. Noise Offset with Reduced V 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) be- comes a larger fraction of an LSB as the size of the LSB is reduced ...
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... APPLICATIONS INFORMATION Noise with Reduced V REF The total input referred noise of the LTC1196 can be reduced to approximately 2mV P-P good bypassing, good layout techniques and minimizing noise on the reference inputs. This noise is insignifi cant 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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... 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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... The power dissipation drops by a factor of fi ve when the supply is reduced to 3V. The converter slows down somewhat but still gives excellent performance rail. With a 3V supply, the LTC1196 converts in 1.6μs, samples at 450kHz, and provides a 500kHz linear- input bandwidth. ...
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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. B15 1196/98 F17 LSB 0 (B0) START Figure 18. D Circuit in Figure 15 LTC1196/LTC1198 word is then put in the transmit register S/D O/S ...
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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) NOTE 3 ...
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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, 2.5Msps Parallel ADC ...