AD774B

Features:

Complete Monolithic 12-Bit A/D Converters with
Reference, Clock, and Three-State Output Buffers
Industry Standard Pinout
High Speed Upgrades for AD574A
8- and 16-Bit Microprocessor Interface
8 s (Max) Conversion Time (AD774B)
15 s (Max) Conversion Time (AD674B)5 V, 10 V, 0 V10 V, 0 V20 V Input Ranges
Commercial, Industrial, and Military Temperature
Range Grades
MIL-STD-883-Compliant Versions Available


Pinout




Specifications

V _CCto Digital Common  . . . . . . . . . . . . . . . . . . .  0 to +16.5 V
V _EE to Digital Common  . . . . . . . . . . . . . . . . . . . .  0 to 16.5 V
V_LOGICto Digital Common  . . . . . . . . . . . . . . . . . . .  0 to +7 V
Analog Common to Digital Common  . . . . . . . . .  ±1 V+0.5 V
Digital Inputs to Digital Common . . .  0.5 V  _LOGICto V
Analog Inputs to Analog Common  . . . . . . . . . . . .  VEE to VCC
20 V _IN to Analog Common  . . . . . . . . . . . . . . . . . . . . . .  ±24 V
REF OUT  . . . . . . . . . . . . . . . . . . Indefinite Short to Common
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Momentary Short to V _CC
Junction Temperature  . . . . . . . . . . . . . . . . . . . . . . . . . . 175°C
Power Dissipation  . . . . . . . . . . . . . . . . . . . . . . . . . . .  825 mW
Lead Temperature, Soldering (10 sec)  . . . . . . . . . . . . . 300°C
Storage Temperature . . . . . . . . . . . . . . . . . .  65°C to +150°C

Description

The AD674B and AD774B are complete 12-bit successive approximation analog-to-digital converters with three-state output buffer circuitry for direct interface to 8- and 16-bit microprocessor busses. A high-precision voltage reference and clock are included on chip, and the circuit requires only power supplies and control signals for operation.
The AD674B and AD774B are pin-compatible with the industry standard AD574A, but offer faster conversion time and busaccess speed than the AD574A and lower power consumption. The AD674B converts in 15 s (maximum) and the AD774B converts in 8 s (maximum).
The monolithic design is implemented us ing Analog Devices' BiMOS II process allowing high-performance bipolar analog circuitry to be combined on the same die with digital CMOS logic. Offset, line arity, and scaling errors are minimized by active laser trimming of thin-film resistors.
Five different grades are available. The J and K grades are specified for operation over the 0°C to 70°C temperature range. The A and B grades are spec ified from 40°C to +85°C, the T grade is specified from 55°C to +125°C. The J and K grades are available in a 28-lead plastic DIP or 28-lead SOIC. All other grades are available in a 28-lead hermetically sealed ceramic DIP.