_______________General Description

The MAX1204 is a 10-bit data-acquisition system

specifically designed for use in applications with mixed

+5V (analog) and +3V (digital) supply voltages. It oper-

ates with a single +5V analog supply or dual ±5V ana-

log supplies, and combines an 8-channel multiplexer,

internal track/hold, and serial interface with high con-

version speed and low power consumption.

A 4-wire serial interface connects directly to

SPI™/Microwire™ devices without external logic, and a

serial strobe output allows direct connection to

TMS320-family digital signal processors. The MAX1204

uses either the internal clock or an external serial-

interface clock to perform successive-approximation

analog-to-digital conversions. The serial interface oper-

ates at up to 2MHz.

The MAX1204 features an internal 4.096V reference and

a reference-buffer amplifier that simplifies gain trim. It

also has a VL pin that supplies power to the digital out-

puts. Output logic levels (3V, 3.3V, or 5V) are determined

by the value of the voltage applied to this pin.

A hard-wired

SHDN pin and two software-selectable

power-down modes are provided. Accessing the serial

interface automatically powers up the device. A quick

turn-on time allows the MAX1204 to be shut down

between conversions, enabling the user to optimize

supply currents. By customizing power-down between

conversions, supply current can drop below 10µA at

reduced sampling rates.

The MAX1204 is available in 20-pin SSOP and DIP

packages, and is specified for the commercial, extend-

ed, and military temperature ranges.

________________________Applications

5V/3V Mixed-Supply Systems

Data Acquisition

Process Control

Battery-Powered Instruments

Medical Instruments

____________________________Features

o 8-Channel Single-Ended or 4-Channel

Differential Inputs

o Operates from +5V Single or ±5V Dual Supplies

o User-Adjustable Output Logic Levels

(2.7V to 5.25V)

o Low Power: 1.5mA (operating mode)

2µA (power-down mode)

o Internal Track/Hold, 133kHz Sampling Rate

o Internal 4.096V Reference

o SPI/Microwire/TMS320-Compatible

4-Wire Serial Interface

o Software-Configurable Unipolar/Bipolar Inputs

o 20-Pin DIP/SSOP

o Pin-Compatible 12-Bit Upgrade: MAX1202

5V, 8-Channel, Serial, 10-Bit ADC

with 3V Digital Interface

________________________________________________________________

Maxim Integrated Products

1

20

19

18

17

16

15

14

13

12

11

1

2

3

4

5

6

7

8

9

10

TOP VIEW

DIP/SSOP

SCLK

CS

DIN

SSTRB

DOUT

VL

GND

REFADJ

REF

SHDN

CH7

CH6

CH5

CH4

CH3

CH2

CH1

CH0

MAX1204

__________________Pin Configuration

19-1179; Rev 0; 1/97

______________Ordering Information

For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800

Typical Operating Circuit appears on last page.

SPI is a registered trademark of Motorola, Inc.

Microwire is a registered trademark of National Semiconductor Corp.

Ordering Information continued at end of data sheet.

PART

MAX1204ACPP

MAX1204BCPP

MAX1204ACAP

0°C to +70°C

0°C to +70°C

0°C to +70°C

TEMP. RANGE PIN-PACKAGE

20 Plastic DIP

20 Plastic DIP

20 SSOP

MAX1204BCAP

0°C to +70°C

20 SSOP

INL

(LSB)

±1/2

±1

±1/2

±1