December 1994
DAC1218/DAC1219
12-Bit Binary Multiplying D/A Converter
General Description
The DAC1218 and the DAC1219 are 12-bit binary, 4-quad-
rant multiplying D to A converters. The linearity, differential
non-linearity and monotonicity specifications for these con-
verters are all guaranteed over temperature. In addition,
these parameters are specified with standard zero and full-
scale adjustment procedures as opposed to the impractical
best fit straight line guarantee.
a microprocessor bus is desirable, the DAC1208 and
DAC1230 series eliminate the need for additional interface
logic.
Features
Y
Linearity specified with zero and full-scale adjust only
Y
Logic inputs which meet TTL voltage level specs (1.4V
logic threshold)
This level of precision is achieved though the use of an
advanced silicon-chromium (SiCr) R-2R resistor ladder net-
work. This type of thin-film resistor eliminates the parasitic
diode problems associated with diffused resistors and al-
b
lows the applied reference voltage to range from 25V to
25V, independent of the logic supply voltage.
Y
g
Works with 10V referenceÐfull 4-quadrant
multiplication
Y
All parts guaranteed 12-bit monotonic
CMOS current switches and drive circuitry are used to
achieve low power consumption (20 mW typical) and mini-
mize output leakage current errors (10 nA maximum).
Unique digital input circuitry maintains TTL compatible input
threshold voltages over the full operating supply voltage
range.
Key Specifications
Y
Current Settling Time
1 ms
12 Bits
Y
Resolution
Y
Linearity (Guaranteed
over temperature)
12 Bits (DAC1218)
11 Bits (DAC1219)
Y
The DAC1218 and DAC1219 are direct replacements for
the AD7541 series, AD7521 series, and AD7531 series with
a significant improvement in the linearity specification. In
applications where direct interface of the D to A converter to
Gain Tempco
1.5 ppm/ C
§
20 mW
Y
Low Power Dissipation
Y
Single Power Supply
5 V to 15 V
DC DC
Typical Application
Connection Diagram
Dual-In-Line Package
TL/H/5691–1
A1
2
A2
4
A3
8
A12
e b
a
a
a
. . .
V
V
OUT
REF
4096
#
J
TL/H/5691–15
e
e
where: AN
AN
1 if digital input is high
0 if digital input is low
Top View
Ordering Information
a
0 C to 70 C
§
b
a
40 C to 85 C
Temperature Range
Package Outline
§
§
§
Non
0.012%
0.024%
DAC1218LCJ-1
DAC1218LCJ
DAC1219LCJ
J18A Cerdip
J18A Cerdip
Linearity
BI-FETTM is a trademark of National Semiconductor Corp.
C
1995 National Semiconductor Corporation
TL/H/5691
RRD-B30M115/Printed in U. S. A.