GC1012B_07 Datasheet, PDF (25/30 Pages) Texas Instruments – 3.3V DIGITAL TUNER CHIP

GC1012B 3.3V DIGITAL TUNER
SLWS138B
5.0 APPLICATION NOTES
5.1 POWER AND GROUND CONNECTIONS
The GC1012B 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 GC1012B 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 GC1012B 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 GC1012B chip may not operate properly if these power and ground guidelines are violated.
5.2 STATIC SENSITIVE DEVICE
The GC1012B 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.
5.3 100 MHZ OPERATION
Care must be taken in generating the clock when operating the GC1012B chip at its full 100 MHz
clock rate. The user must insure that the clock is above 2 volts for at least 4 nanoseconds and is below 0.8
volts for at least 4 nanoseconds. At 1000 MHz the clock period is only 10 nanoseconds so that the clock
must have a duty cycle of exactly 50%, and the rise and fall times can only be 1 nanosecond each. One
must also be careful to prevent clock undershoot below ground. An ideal clock at 100 MHz would be a
square wave with a low voltage of 0.5 volts and a high voltage of 2.5 volts.
5.4 REDUCED VOLTAGE OPERATION
The power consumed by the GC1012B chip can be greatly reduced by operating the chip at the
lowest V_CC voltage which will meet the application’s timing requirements. When operating at a reduced
voltage, GRAYCHIP recommends driving the GC1012B chip inputs with 5 volt to 3 volt interface chips.
Texas Instruments Incorporated
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