ADC08161

500 ns A/D Converter with S/H Function and

2.5V Bandgap Reference

General Description

Using a patented multi-step A/D conversion technique, the

8-bit ADC08161 CMOS A/D converter offers 500 ns conver-

sion time, internal sample-and-hold (S/H), a 2.5V bandgap

reference, and dissipates only 100 mW of power. The

ADC08161 performs an 8-bit conversion with a 2-bit voltage

estimator that generates the 2 MSBs and two low-resolution

(3-bit) flashes that generate the 6 LBSs.

Input signals are tracked and held by the input sampling cir-

cuitry, eliminating the need for an external sample-and-hold.

The ADC08161 can perform accurate conversions of

full-scale input signals at frequencies from DC to typically

more than 300 kHz (full power bandwidth) without the need

of an external sample-and-hold (S/H).

For ease of interface to microprocessors, this part has been

designed to appear as a memory location or I/O port without

the need for external interfacing logic.

Key Specifications

n Resolution

8 Bits

560 ns max (WR-RD Mode)

n Full power bandwidth

300 kHz (typ)

n Throughput rate

1.5 MHz min

n Power dissipation

100 mW max

n Total unadjusted error

Features

n No external clock required

n Analog input voltage range from GND to V

+

n 2.5V bandgap reference

Applications

n Mobile telecommunications

n Hard-disk drives

n Instrumentation

n High-speed data acquisition systems

Block Diagram

DS011149-1

June 1999

© 1999 National Semiconductor Corporation

DS011149

www.national.com