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
– VREF to VOUT 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
VREF = 1 V p-p @ 1 MHz
• VREF/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 VREF to output up to 10 MHz (typ),
fast output settling time, and VREF 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 IVTM) 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