Bt121
Monolithic CMOS Triple 8-Bit VIDEODAC
The Bt121 is a triple 8-bit VIDEODAC designed specifically for
high-performance, high-resolution color graphics.
This device offers a higher level of integration than previous VIDEODAC
designs. Included is an on-chip voltage reference to simplify use of the
device.
The Bt121 generates RS-343A-compatible video signals into a
doubly-terminated 75 Ω load, and RS-170-compatible video signals into a
singly-terminated 75 Ω load, without requiring external buffering. Both the
differential and integral linearity errors of the D/A converters are guaranteed
to be a maximum of ±1 LSB over the full temperature range.
Functional Block Diagram
Reference
Amplifier
1.2 V
8
•
•
•
•
•
DAC
8
8
B0-B7
R
E
G
I
S
T
E
R
DAC
IOG
DAC
IOB
8
BLANK*
VAA
IOR
8
SYNC*
L121001, Ref. G
COMP
8
R0-R7
G0-G7
• 80, 50 MHz Operation
• Triple 8-bit D/A Converters
• Optional Internal Voltage
Reference
• RS-343A-Compatible Outputs
• TTL-Compatible Inputs
• +5 V CMOS Monolithic
Construction
• 44-pin PLCC Package
• Typical Power Dissipation:
600 mW
Applications
VREF FS ADJUST
CLOCK
Product Features
AGND
High-Resolution Color Graphics
CAE/CAD/CAM
Image Processing
Video Reconstruction
Instrumentation
