LTC1594L/LTC1598L 4- and 8-Channel, 3V Micropower Sampling 12-Bit Serial I/O A/D Converters FEATURES DESCRIPTIO n 12-Bit Resolution on 3V Supply The LTC 1594L/LTC1598L are 3V micropower, 12-bit n Low Supply Current: 160A Typ sampling A/D converters that feature 4- and 8-channel n Auto Shutdown to 1nA multiplexers, respectively. They typically draw only 160A n Guaranteed 3/4LSB Max DNL of supply current when converting and automatically n Guaranteed 2.7V Operation power down to a typical supply current of 1nA between (5V Versions Available: LTC1594/LTC1598) conversions. The LTC1594L is available in a 16-pin SO n Multiplexer: 4-Channel MUX (LTC1594L) package and the LTC1598L is packaged in a 24-pin 8-Channel MUX (LTC1598L) SSOP. Both operate on a 3V supply. The 12-bit, switched- n Separate MUX Output and ADC Input Pins capacitor, successive approximation ADCs include a n MUX and ADC May Be Controlled Separately sample-and-hold. n Sampling Rate: 10.5ksps On-chip serial ports allow efficient data transfer to a wide TM n I/O Compatible with QSPI, SPI and MICROWIRE , etc. range of microprocessors and microcontrollers over three n Small Package: 16-Pin Narrow SO (LTC1594L) or four wires. This, coupled with micropower consump- 24-Pin SSOP (LTC1598L) tion, makes remote location possible and facilitates trans- U mitting data through isolation barriers. APPLICATIO S The circuit can be used in ratiometric applications or with n Pen Screen Digitizing an external reference. The high impedance analog inputs n Battery-Operated Systems and the ability to operate with reduced spans (to 1.5V full n Remote Data Acquisition scale) allow direct connection to sensors and transducers n Isolated Data Acquisition in many applications, eliminating the need for gain stages. n Battery Monitoring , LTC and LT are registered trademarks of Linear Technology Corporation. n Temperature Measurement MICROWIRE is a trademark of National Semiconductor Corporation. TYPICAL APPLICATION 12W, 8-Channel, 12-Bit ADC Samples at 200Hz and Runs Off a 3V Supply OPTIONAL ADC FILTER Supply Current vs Sample Rate 3V 1k 1F 1000 T = 25C A V = 2.7V CC 18 17 16 15, 19 1F V = 2.5V REF MUXOUT ADCIN V V REF CC f = 200kHz CLK 20 CH0 SERIAL DATA LINK 100 MICROWIRE AND 21 CH1 10 CSADC SPI COMPATABLE 22 CH2 6 CSMUX ANALOG 23 CH3 5, 14 12-BIT 8-CHANNEL INPUTS CLK + SAMPLING MPU 24 CH4 MUX 7 0V TO 3V D 10 ADC IN RANGE 1 CH5 11 D OUT 2 CH6 12 3 CH7 NC LTC1598L 13 8 COM NC 1 GND 0.1 1 10 100 1594L/98L TA01 4, 9 SAMPLE FREQUENCY (kHz) 1594L/98L TA02 15948lfb 1 SUPPLY CURRENT (A) U ULTC1594L/LTC1598L ABSOLUTE MAXIMUM RATINGS (Notes 1, 2) Supply Voltage (V ) to GND................................... 12V Power Dissipation.............................................. 500mW CC Voltage Operating Temperature Range Analog Reference .................... 0.3V to (V + 0.3V) LTC1594LCS/LTC1598LCG ..................... 0C to 70C CC Analog Inputs .......................... 0.3V to (V + 0.3V) LTC1594LIS/LTC1598LIG ................. 40C to 85C CC Digital Inputs .........................................0.3V to 12V Storage Temperature Range ................. 65C to 150C Digital Output .......................... 0.3V to (V + 0.3V) Lead Temperature (Soldering, 10 sec).................. 300C CC PACKAGE/ORDER INFORMATION ORDER PART TOP VIEW ORDER PART NUMBER NUMBER 1 24 CH4 CH5 TOP VIEW 2 23 CH3 CH6 LTC1594LCS LTC1598LCG CH0 1 16 V 3 22 CH2 CC CH7 LTC1594LIS LTC1598LIG CH1 2 15 MUXOUT 4 21 CH1 GND CH2 3 14 D 5 20 CH0 IN CLK CH3 4 13 CSMUX 6 19 V CSMUX CC ADCIN 5 12 CLK 7 18 MUXOUT D IN V 6 11 V 8 17 ADCIN REF CC COM COM 7 10 D 9 16 V OUT GND REF GND 8 9 CSADC 10 15 V CSADC CC 11 14 CLK D OUT S PACKAGE 16-LEAD PLASTIC SO 12 13 NC NC T = 125C, = 120C/ W JMAX JA G PACKAGE 24-LEAD PLASTIC SSOP T = 150C, = 110C/ W JMAX JA Consult factory for Military grade parts. RECOM ENDED OPERATING CONDITIONS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25C. (Note 5) A SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V Supply Voltage (Note 3) 2.7 3.6 V CC f Clock Frequency V = 2.7V (Note 4) 200 kHz CLK CC t Total Cycle Time f = 200kHz 95 s CYC CLK t Hold Time, D After CLK V = 2.7V 450 ns hDI IN CC t Setup Time CS Before First CLK (See Operating Sequence) V = 2.7V 2 s suCS CC t Setup Time, D Stable Before CLK V = 2.7V 600 ns suDI IN CC t CLK High Time V = 2.7V 1.5 s WHCLK CC t CLK Low Time V = 2.7V 1.5 s WLCLK CC t CS High Time Between Data Transfer Cycles f = 200kHz 25 s WHCS CLK t CS Low Time During Data Transfer f = 200kHz 70 s WLCS CLK 15948lfb 2 U U U U WW UUW U WWW