MP7641
8-Channel Voltage Output
10 MHz Input Bandwidth 8-Bit
Multiplying DACs with
Serial Digital Port
FEATURES
•
8 Independent 2-Quadrant Multiplying 8-Bit DACs
•
Dual Positive (+10 V and +5 V) Supplies or
Dual (+5 V) Supplies Capability
•
High Speed:
– 12.5 MHz Digital Clock Rate
– V
REF to
V
OUT
Settling Time: 150ns to 8–bit
(typ)
– Voltage Reference Input Bandwidth:
10 MHz
•
Low Power: 150mW
•
Low AC Voltage Reference Feedthrough
•
Excellent Channel-to-Channel Isolation
•
DNL = +0.8 LSB, INL = +1 LSB (typ)
•
DACs Matched to +0.5% (typ)
•
Chip Select Available: MP7651
•
Low Harmonic Distortion: 0.25% typical with
V
REF
= 1 V p-p @ 1 MHz
•
V
REF
/2 Output Preset Level
•
Latch-Up Free
•
ESD Protection: 2000 V Minimum
APPLICATIONS
•
Direct High-Frequency Automatic Gain Control
•
Video AGC & CCD Level AGC
•
Convergence Adjustment for High-Resolution
Monitors (Workstations)
GENERAL DESCRIPTION
The MP7641 is ideal for direct gain control of video, compos-
ite video, CCD and other high frequency analog signals. The de-
vice includes 8-channels of high speed, high bandwidth, two
quadrant multiplying, 8-bit accurate digital-to-analog converter.
It includes an output drive buffer per channel capable of driving a
+1mA (typ) to a load. DNL of better than +0.8 LSB is achieved
with a channel-to-channel matching of better than 0.5% (typ).
Stability, matching, and precision of the DACs are achieved by
using EXAR’s thin film technology. Also, excellent channel-to-
channel isolation is achieved with EXAR’s BiCMOS process
which cannot be achieved using a typical CMOS technology.
An open loop architecture (patent pending) provides wide
small signal bandwidth from V
REF
to output up to 10 MHz (typ),
fast output settling time, and V
REF
feedthrough isolation of
–65dB or better. In addition, low distortion in the order of 0.25%
with a 1 V p-p, 1 MHz signal is achieved.
The combination of a constant input Z and the ability to vary
AGND within +300 mV allows flexibility for optimum system de-
sign.
The MP7641 has a serial data 3-wire standard
µ
-processor
logic interface to reduce pin count, package size, and board wire
(space).
The MP7641 is fabricated on a junction isolated, high speed
BiCMOS (BiCMOS IV
TM
) process with thin film resistors. This
process enables precision high speed analog/digital (mixed-
mode) circuits to be fabricated on the same chip.
Rev. 2.00
1