Texas Instruments Incorporated - 25 -
GC3021A 3.3V MIXER AND CARRIER REMOVAL CHIP SLWS137A
This document contains information which may be changed at any time without notice
6.0 APPLICATION NOTES
6.1 POWER AND GROUND CONNECTIONS
The GC3021A chip is a very high performance chip which requires solid power and ground
connections to avoid noise on the V
CC
and GND pins. If possible the GC3021A chip should be mounted on
a circuit board with dedicated power and ground planes and with at least two decoupling capacitors (0.01
and 0.1 µf) adjacent to each GC3021A chip. If dedicated power and ground planes are not possible, then
the user should place decoupling capacitors adjacent to each V
CC
and GND pair.
IMPORTANT
The GC3021A chip may not operate properly if these power and ground guidelines are violated.
6.2 STATIC SENSITIVE DEVICE
The GC3021A chip is fabricated in a high performance CMOS process which is sensitive to the high
voltage transients caused by static electricity. These parts can be permanently damaged by static electricity
and should only be handled in static free environments.
6.3 REDUCED VOLTAGE OPERATION
The power consumed by the GC3021A chip can be greatly reduced by operating the chip at the
lowest V
CC
voltage which will meet the application’s timing requirements.
6.4 HIGH SPEED MIXER
The GC3021A chip can be used with two GC2011 filter chips to implement a high speed quadrature
down converter capable of accepting data rates up to 200 MHz, tuning to a desired frequency and outputting
100 MHz complex data. A block diagram of the suggested configuration is shown below:
Figure 7. HIGH SPEED MIXER EXAMPLE
The GC2011 Digital filter chips are used in a decimate by two, double rate in, full rate out mode.
I
Q
CK
I
EVEN
I
ODD
Q
EVEN
Q
ODD
A
B
A
B
GC2011
GC3021A
GC2011
I
Q
Even
Odd
Clock
