L64733 LSI Logic Corporation, L64733 Datasheet - Page 17

• Manufacturer Part Number: L64733
• Description: Tuner/receiver Chipset
• Manufacturer: LSI Logic Corporation

Analog-to-Digital Converter (ADC) Interface
AGC Control Interface
The ADC module converts the incoming IVIN and QVIN signals into an
internal 6-bit digital representation for processing. The following pins
support the ADC module.
ADCVDDI/Q
ADCVSSI/Q
VREFP
VREFN
VMID
The AGC Control interface contains signals used for power control.
AGC1, AGC2 Power Control Signals
L64733/L64734 Tuner and Satellite Receiver Chipset
ADC Power
These are the analog power supply pins for the ADC
module; they are normally connected to the system
power (V
ADC Analog Ground
These are the analog ground pins for the ADC module;
they are normally connected to the system ground plane.
Reference Voltage, Positive
ADC reference voltage generated by the on-chip
bandgap-based generator. Bypass to GND using a
0.1 F capacitor.
Reference Voltage, Negative
ADC reference voltage generated by the on-chip
bandgap-based generator. Bypass to GND using a
0.1 F capacitor.
Reference Voltage, Middle
ADC reference voltage generated by the on-chip
bandgap-based generator. Bypass to GND using a
0.1 F capacitor.
The AGC1 and AGC2 signals are the positive
modulated output used for power control. These signals
can each drive an external passive RC filter that feeds a
gain control stage for dual-stage AGC. For a single-stage
AGC, AGC1 can be used.
DD
) plane.
Input/Output
Input/Output
Input/Output
Output
Input
Input
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