
Exar Corporation
GENERAL DESCRIPTION
The MP7643 is ideal for digital gain control of high frequency analog signals such as video, composite video and CCD. The device includes 4-channels of high speed, wide 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) load. DNL of better than +0.5 LSB is achieved with a channel-to-channel matching of typically 0.5%. Stability, matching, and precision of the DACs are achieved by using MPS’ thin film technology. Excellent channel-to-channel isolation is also achieved with MPS’ BiCMOS process which cannot be achieved using a typical CMOS technology.
FEATURES
• Programmable Gain
• 4 Independent 2-Quadrant Multiplying 8-Bit DACs with Output Amplifiers
• 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: 15 MHz
• Very Low Noise Gain Control
• Low Power: 80mW
• Low AC Voltage Reference Feedthrough
• Excellent Channel-to-Channel Isolation
• DNL = +0.5 LSB, INL = +1 LSB (typ)
• DACs Matched to +0.5% (typ)
• Low Harmonic Distortion: 0.25% typical with VREF = 1 V p-p @ 1 MHz
• 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)
• Multiplier Replacement