1FEATURES

2• Easy Interface to All Microprocessors

• Operates Ratiometrically or with 5 VDC or

Analog Span Adjusted Voltage Reference

• No Zero or Full-Scale Adjust Required

• 8-Channel Multiplexer with Address Logic

• 0V to VCC Input Range

• Outputs meet TTL Voltage Level Specifications

• ADC0808 Equivalent to MM74C949

• ADC0809 Equivalent to MM74C949-1

KEY SPECIFICATIONS

• Resolution: 8 Bits

• Total Unadjusted Error: ±½ LSB and ±1 LSB

• Single Supply: 5 VDC

• Low Power: 15 mW

• Conversion Time: 100 μs

DESCRIPTION

The ADC0808, ADC0809 data acquisition component

is a monolithic CMOS device with an 8-bit analog-to-

digital converter, 8-channel multiplexer and

microprocessor compatible control logic. The 8-bit

A/D converter uses successive approximation as the

conversion technique. The converter features a high

impedance chopper stabilized comparator, a 256R

voltage divider with analog switch tree and a

successive approximation register. The 8-channel

multiplexer can directly access any of 8-single-ended

analog signals.

The device eliminates the need for external zero and

full-scale adjustments. Easy interfacing to

microprocessors is provided by the latched and

decoded multiplexer address inputs and latched TTL

TRI-STATE outputs.

The design of the ADC0808, ADC0809 has been

optimized by incorporating the most desirable aspects

of several A/D conversion techniques. The ADC0808,

ADC0809 offers high speed, high accuracy, minimal

temperature dependence, excellent long-term

accuracy and repeatability, and consumes minimal

power. These features make this device ideally suited

to applications from process and machine control to

consumer and automotive applications. For 16-

channel multiplexer with common output (sample/hold

port) see ADC0816 data sheet. (See AN-247

(Literature Number SNOA595) for more information.)