LTC1594 Linear Technology, LTC1594 Datasheet
LTC1594
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LTC1594 Summary of contents
Page 1
... They typically draw only 320 A of supply current when converting and automatically power down to a typical supply current of 1nA between conversions. The LTC1594 is available in a 16-pin SO package and the LTC1598 is packaged in a 24-pin SSOP. Both operate supply. The 12-bit, switched-capacitor, successive approximation ADCs include a sample-and-hold ...
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... CS Low Time During Data Transfer WLCS 2 U RATINGS Power Dissipation .............................................. 500mW Operating Temperature Range + 0.3V) LTC1594CS/LTC1598CG ......................... 0.3V) LTC1594IS/LTC1598IG ..................... – Storage Temperature Range ................. – 150 C + 0.3V) Lead Temperature (Soldering, 10 sec).................. 300 ORDER PART NUMBER 1 CH5 ...
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... CYC CLK CLK = 760 s, f 25kHz CYC CLK 320kHz CYC CLK LTC1594/LTC1598 (Note 5) LTC1594IS/LTC1598IG MAX MIN TYP MAX 3 1. 0.05V CC – 0.05V 0.05V CC 200 200 200 200 ...
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... Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: All voltage values are with respect to GND. Note 3: These devices are specified at 5V. Consult factory for 3V specified devices (LTC1594L/LTC1598L). Note 4: Increased leakage currents at elevated temperatures cause the S/H to droop, therefore it is recommended that f CLK ...
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... REF 16.8kHz SMPL 100 INPUT FREQUENCY (kHz) LTC1594/LTC1598 Change in Linearity vs Reference Voltage – 0 .50 T – CLK – 0 .40 f SMPL – 0 .35 – 0 .30 – 0 .25 – 0 .20 – 0 .15 – 0 .10 – ...
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... LTC1594/LTC1598 W U TYPICAL PERFORMANCE CHARACTERISTICS Attenuation vs Input Frequency REF 16.8kHz SMPL 100 1 10 100 1000 10000 INPUT FREQUENCY (kHz) 1594/98 G13 Power Supply Feedthrough vs Ripple Frequency 20mV) CC RIPPLE ...
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... For normal operation drive this pin in parallel with CSMUX. D (Pin 11): Digital Data Output. The A/D conversion OUT result is shifted out of this output. NC (Pin 12): No Connection. NC (Pin 13): No Connection. CLK (Pin 14): Shift Clock. This input should be tied to Pin 5. LTC1594/LTC1598 7 ...
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... REF CH0 CSADC 13 21 CH1 CSMUX 12 22 CH2 CLK 14 23 CH3 D ADC CH4 D OUT 1 CH5 LTC1594 2 CH6 8 3 CH7 8 COM and t Voltage Waveforms for OUT TEST POINT 1594/98 TC01 LTC1598 15, 19 MUXOUT ADCIN V V REF CC 10 ...
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... NOTE 1: WAVEFORM 1 IS FOR AN OUTPUT WITH INTERNAL CONDITIONS SUCH 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. LTC1594/LTC1598 Voltage Waveforms for ...
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... Supply Current vs Sample Rate). The ADCs automatically power down when not performing conversions, drawing only leakage current. The LTC1594 is available in a 16-pin narrow SO package and the LTC1598 is packaged in a 24-pin SSOP. Both devices operate on a single supply from 4 ...
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... CH0 TO CH7 ADCIN = MUXOUT COM = GND Figure 2. LTC1594/LTC1598 Operating Sequence Example: All Channels Off Data Transfer The CLK synchronizes the data transfer with each bit being transmitted on the falling CLK edge and captured on the rising CLK edge in both transmitting and receiving systems ...
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... COM pin. Tables 1 and 2 show the various bit combinations for the LTC1594/LTC1598 channel selection. Table 1. Logic Table for the LTC1594 Channel Selection CHANNEL STATUS EN D2 ...
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... Data is transmitted in both directions on a single wire. The processor pin connected to this data line should be configurable as either an input or an output. The LTC1594/ LTC1598 will take control of the data line after CS falling and before the 6th falling CLK while the processor takes control of the data line when CS is high (see Figure 3) ...
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... Figure 5. Use Separate Chip Selects to Maximize Sample Rate MUXOUT/ADCIN Loop Economizes Signal Conditioning The MUXOUT and ADCIN pins of the LTC1594/LTC1598 form a very flexible external loop that allows Program- mable Gain Amplifier (PGA) and/or processing analog input signals prior to conversion. This loop is also a cost effective way to perform the conditioning, because only one circuit is needed instead of one for each channel ...
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... U APPLICATIONS INFORMATION BOARD LAYOUT CONSIDERATIONS Grounding and Bypassing The LTC1594/LTC1598 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. The V pin should be bypassed to the ground plane with tantalum capacitor with leads as short as possible ...
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... Source Resistance The analog inputs of the LTC1594/LTC1598 look like a 20pF capacitor (C and gets switched between the selected “analog” and IN “ ...
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... Conversion speed (CLK frequency Offset with Reduced V The offset of the LTC1594/LTC1598 has a larger effect on the output code when the ADCs are 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 Change in ...
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... ADC and is directly related to S/( the equation: ENOB = [S/( – 1.76]/6.02 where S/( expressed in dB. At the maximum sampling rate of 16.8kHz with a 5V supply, the LTC1594/ LTC1598 maintain above 11 ENOBs at 10kHz input frequency. Above 10kHz the ENOBs gradually decline, as shown in Figure 11, due to increasing second harmonic distortion ...
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... APPLICATIONS INFORMATION specification in the Dynamic Accuracy table includes the 2nd through 5th harmonics. With a 7kHz input signal, the LTC1594/LTC1598 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 nonlin- earity can produce intermodulation distortion (IMD) in addition to THD ...
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... LTC1594/LTC1598 U TYPICAL APPLICATIONS LDA #$52 Configuration data for serial peripheral control register (Interrupts disabled, output enabled, master, Norm = Clk/16) STA $0A Load configuration data into location $0A (SPCR) LDA #$FF Configuration data for I/O ports (all bits are set as outputs) STA $04 Load configuration data into Port A DDR ($04) ...
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... The complete circuit consumes approximately 800 A from a single 5V supply. 24 CH4 23 CH3 22 CH2 21 CH1 C2 20 CH0 REF CLK 13 NC DATA OUT DATA IN CHIP SELECT CLOCK LTC1594/LTC1598 offset sine input. P-P 5V 0.015 7.5k 7.5k + 1/2 0.03 F LT1368 – 7.5k + 1/2 0.015 F LT1368 – 0.03 F 1594/98 TA05 C1 0 ...
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... Combined with the LTC1391, the system can expand to eight channels and eight gains for each channel. Using the LTC1594, the PGA is reduced to four gains. The output of the LT1368 drives the ADCIN and the resistor ladder. The resistors above the selected MUX channel form the feedback for the LT1368 ...
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... LTC1594/LTC1598 0.318 – 0.328* (8.07 – 8.33 0.301 – 0.311 (7.65 – 7.90) 0.068 – 0.078 (1.73 – 1.99) 0.002 – 0.008 (0.05 – 0.21) G24 SSOP 0595 0.386 – ...
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... SO, 5V, Micropower LTC1286 Multiplexed 12-Bit ADC LTC1289 Multiplexed 3V, 1A, 12-Bit ADC LTC1415 5V High Speed Parallel 12-Bit ADC LTC1594L 4-Channel, 3V Micropower 12-Bit ADC LTC1598L 8-Channel, 3V Micropower 12-Bit ADC Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 TELEX: 499-3977 www.linear-tech.com ...