MP7614
15 V CMOS
Multiplying 14-Bit
Digital-to-Analog Converter
FEATURES
•
•
•
•
Full Four-Quadrant Multiplication
Excellent Stability Over Temperature and Time
Guaranteed Monotonic
TTL/5 V CMOS Compatible
•
Low Sensitivity to Output Amplifier V
OS
•
Low Glitch Energy
•
16-Bit Version: MP7616
GENERAL DESCRIPTION
The MP7614 is a high density 14-bit CMOS multiplying Digi-
tal-to-Analog Converter. Silicon nitride passivation and un-
trimmed silicon chromium resistors have been combined to pro-
vide long term stability and reliability. Using the most significant
bit (MSB) segmentation technique, the MP7614 features 13-bit
(0.012%) differential and 12-bit (0.01%) integral linearity.
To achieve 13-bit linearity without laser trim, the MP7614 digi-
tally decodes the four MSB’s into 15 equal current sources,
rather than the standard binary-weighted sources. Each resis-
tor contributes only 1/16 full scale output thus reducing the
matching accuracy requirement of the resistor and CMOS
switches from 0.0015% to 0.006%.
The decoding technique achieves an eightfold improvement
in differential linearity stability over temperature, an eightfold im-
provement in relative accuracy due to aging effects (long term
stability), a fourfold improvement in glitch amplitude, and a ten-
fold reduction in sensitivity to output amplifier offset voltage.
SIMPLIFIED BLOCK DIAGRAM
V
DD
V
REF
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
10-Bit
DAC
I
OUT2
I
OUT1
To Switches
R
FB
4 to 15 Decoder
To 10-Bit DAC
GND
1
(MSB)
4
5
14
(LSB)
Rev. 2.00
1
EXAR [ EXAR CORPORATION ]
