Rainbow Electronics ADC0817 - Manual

ADC0816/ADC0817
8-Bit µP Compatible A/D Converters with 16-Channel
Multiplexer
General Description
The ADC0816, ADC0817 data acquisition component is a
monolithic CMOS device with an 8-bit analog-to-digital con-
verter, 16-channel multiplexer and microprocessor compat-
ible 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 succes-
sive approximation register. The 16-channel multiplexer can
directly access any one of 16-single-ended analog signals,
and provides the logic for additional channel expansion. Sig-
nal conditioning of any analog input signal is eased by direct
access to the multiplexer output, and to the input of the 8-bit
A/D converter.
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 ADC0816, ADC0817 has been optimized
by incorporating the most desirable aspects of several A/D
conversion techniques. The ADC0816, ADC0817 offers high
speed, high accuracy, minimal temperature dependence, ex-
cellent 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 similar perfor-
mance in an 8-channel, 28-pin, 8-bit A/D converter, see the
ADC0808, ADC0809 data sheet. (See AN-258 for more in-
formation.)
Features
n Easy interface to all microprocessors, or operates “stand
alone”
n Operates ratiometrically or with 5 V
DC
or analog span
adjusted voltage reference
n 16-channel multiplexer with latched control logic
n Outputs meet TTL voltage level specifications
n 0V to 5V analog input voltage range with single 5V
supply
n No zero or full-scale adjust required
n Standard hermetic or molded 40-pin DIP package
n Temperature range −40˚C to +85˚C or −55˚C to +125˚C
n Latched TRI-STATE output
n Direct access to “comparator in” and “multiplexer out” for
signal conditioning
n ADC0816 equivalent to MM74C948
n ADC0817 equivalent to MM74C948-1
Key Specifications
n Resolution: 8 Bits
n Total Unadjusted Error: ± 1 ⁄ 2 LSB and ± 1 LSB
n Single Supply: 5 V
DC
n Low Power: 15 mW
n Conversion Time: 100 µs
TRI-STATE ® is a registered trademark of National Semiconductor Corporation.
December 1994
ADC0816/ADC0817
8-Bit
µP
Compatible
A/D
Converters
with
16-Channel
Multiplexer
© 1997 National Semiconductor Corporation DS005277 www.national.com