TL/H/5676
ADC1205/ADC1225
12-Bit
Plus
Sign
m
P
Compatible
A/D
Converters
June 1994
ADC1205/ADC1225 12-Bit Plus Sign
mP Compatible A/D Converters
General Description
The ADC1205 and ADC1225 are CMOS, 12-bit plus sign
successive approximation A/D converters. The 24-pin
ADC1205 outputs the 13-bit data result in two 8-bit bytes,
formatted high-byte first with sign extended. The 28-pin
ADC1225 outputs a 13-bit word in parallel for direct inter-
face to a 16-bit data bus.
Negative numbers are represented in 2’s complement data
format. All digital signals are fully TTL and MOS compatible.
A unipolar input (0V to 5V) can be accommodated with a
single 5V supply, while a bipolar input (b5V to a5V) re-
quires the addition of a 5V negative supply.
The ADC1205C and ADC1225C have a maximum non-lin-
earity of 0.0224% of Full Scale.
Key Specifications
Y
Resolution—12 bits plus sign
Y
Linearity Error—g1 LSB
Y
Conversion Time—100 ms
Features
Y
Compatible with all mPs
Y
True differential analog voltage inputs
Y
0V to 5V analog voltage range with single 5V supply
Y
TTL/MOS input/output compatible
Y
Low power—25 mW max
Y
Standard 24-pin or 28-pin DIP
Connection and Functional Diagrams
Dual-In-Line Package
TL/H/5676–1
Top View
Dual-In-Line Package
TL/H/5676–2
Top View
TL/H/5676–3
See Ordering Information
TRI-STATE is a registered trademark of National Semiconductor Corporation.
C
1995 National Semiconductor Corporation RRD-B30M115/Printed in U. S. A.