Document
19-0009; Rev 2; 8/95
NUAL KIT MA ATION U EET L H A S V A E S DAT W O L L FO
±18-Bit ADC with Serial Interface
____________________________Features
o Low Supply Current: 60µA (Normal Operation) 1µA (Sleep-Mode Operation) o ±0.006% FSR Accuracy at 16 Conv/sec o Low Noise: 15µVRMS o Serial I/O Interface with Programmed Output for Mux and PGA o Performs up to 100 Conv/sec o ±2pA Input Current o 50Hz/60Hz Rejection
_______________General Description
The MAX132 is a CMOS, 18-bit plus sign, serial-output, analog-to-digital converter (ADC). Multi-slope integration provides high-resolution conversions in less time than standard integrating ADCs, allowing operation up to 100 conversions per second. Low conversion noise provides guaranteed operation with ±512mV full-scale input range (2µV/LSB). A simple 4-wire serial interface connects easily to all common microprocessors, and twos-complement output coding simplifies bipolar measurements. Typical supply current is only 60µA and is reduced to 1µA in sleep mode. Four serially programmed digital outputs can be used to control an external multiplexer or programmable-gain amplifier. The MAX132 comes in 24-pin narrow DIP and wide SO packages, and is available in commercial and extended temperature grades. High resolution, compact size, and low power make this device ideal for data loggers, weigh scales, data-acquisition systems, and panel meters.
MAX132
______________Ordering Information
PART MAX132CNG MAX132CWG MAX132C/D MAX132ENG MAX132EWG MAX132MRG TEMP. RANGE 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C -55°C to +125°C PIN-PACKAGE 24 Narrow Plastic DIP 24 Wide SO Dice* 24 Narrow Plastic DIP 24 Wide SO 24 Narrow CERDIP**
________________________Applications
Remote Data Acquisition Battery-Powered Instruments Industrial Process Control Transducer-Signal Measurement Pressure, Flow, Temperature, Voltage Current, Resistance, Weight
* Contact factory for dice specifications. ** Contact factory for availability and processing to MIL-STD-883.
________________Functional Diagram
__________________Pin Configuration
TOP VIEW
CREFCS SCLK EOC DIN DOUT
CREF+
V+ 602k
+5V
CS 1 DIN 2 DOUT 3
24 V+ 23 BUF OUT 22 INT OUT 21 INT IN
BUF OUT INT OUT INT IN REF+ REF4.7nF
SCLK 4 OSC2 5 OSC1 6 P0 7 ±512mV INPUT P1 8 P2 9 P3 10 EOC 11 DGND 12
MAX132
20 CREF19 CREF+ 18 REF+ 17 REF16 AGND 15 IN LO 14 IN HI 13 V-
MAX132
P0 P1 P2 P3 OSC1
AGND IN LO IN HI VDGND OSC2 -5V
DIP/SO ________________________________________________________________ Maxim Integrated Products 1
Call toll free 1-800-998-8800 for free samples or literature.
±18-Bit ADC with Serial Interface MAX132
ABSOLUTE MAXIMUM RATINGS
Supply Voltage V+ to DGND ..............................................-0.3V < V+ < +6.0V V- to DGND ................................................+0.3V < V- < -9.0V V+ to V- ............................................................................+15V Analog Input Voltage (any input).....................................V+ to VDigital Input Voltage .....................(DGND - 0.3V) to (V+ + 0.3V) Continuous Power Dissipation Narrow Plastic DIP (derate 8.70mW/°C above +70°C)....478mW Wide SO (derate 11.76mW/°C above +70°C)..............647mW Narrow CERDIP (derate 12.50mW/°C above +70°C) ..688mW Operating Temperature Ranges MAX132C_ _ .......................................................0°C to +70°C MAX132E_ _ ....................................................-40°C to +85°C MAX132MRG .................................................-55°C to +125°C Storage Temperature Range .............................-65°C to +160°C Lead Temperature (soldering, 10sec) .............................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V+ = 5V, V- = -5V, DGND = AGND = IN LO = REF- = 0V, REF+ = 545mV, RINT = 602kΩ, CINT = 0.0047µF, CREF = 0.1µF, fCLK = 32,768Hz, 60Hz mode, TA = TMIN to TMAX, unless otherwise noted.) PARAMETER ACCURACY Resolution Zero Error Integral Nonlinearity Rollover Error Conversion Time Input Voltage Range CONDITIONS (Note 1) VIN HI = 0V (Notes 2, 3) (Note 4) TA = +25°C TA = TMIN to TMAX TA = +25°C TA = +25°C TA = TMIN to TMAX 63 ±2 ±12 ±0.009 ±0.25 ±512 ±10 ±250 ±0.032 ±0.50 ±3.0 ±3.1 ±1.5 ±5 5.5 -4.5 ±0.0061 ±0.0168 ±0.0061 ±0.0168 125 -65 -60 10 -10 ±2 0 ±0.0015 0 MIN TYP MAX ±18 ±0.0076 ±0.0168 ±0.006 ±0.010 ±0.032 UNITS Bits % of FSR % of FSR % of FSR ms mV pA % of FSR V % of FSR µV ppm/°C ppm/°C V V % of FSR % of FSR µA µA µA µA µA µA
fCLK = 32.768Hz IN HI to IN LO, for specified accuracy TA = +25°C Leakage Current IN HI, IN LO TA = TMIN to TMAX VCM = ±500mV Co.