L64704 LSI Logic Corporation, L64704 Datasheet - Page 79

• Manufacturer Part Number: L64704
• Description: Satellite Decoder Technical Manual 5/97
• Manufacturer: LSI Logic Corporation

CAR_VCO_SWAP
CAR_VCO2N/P
CAR_VCO1N/P
Group 4 Registers
without achieving carrier lock, or when the constellation
has locked at 45˚.
Swap VCO Output Polarity
Set this bit to invert the polarities of the CAR_VCOxN/P
pins. It should be toggled whenever the carrier sweep
reaches its limit without achieving carrier lock, or when
the constellation has locked at 45˚.
Outputs Active or 3-state
Program this bit to enable or disable the outputs of the
second Sigma Delta differential pair. For low bit rate
applications that use an external DAC, you must enable
both Sigma-Delta outputs by setting Carrier Loop Config-
uration Register bits [5:4] to zero. For more information,
see Section
This bit should always be set to 0 when CAR_OUT_SEL
is set to 1.
Outputs Active or 3-state
Program this bit to enable or disable the outputs of the first
Sigma Delta differential pair. For low bit rate applications
that use an external DAC, you must enable both Sigma-
Delta outputs by setting Carrier Loop Configuration
D7
0
1
D6
0
1
D5
0
1
Sweep Direction
Normal
Reversed
Polarity
Normal
Swapped (N and P Inverted)
CAR_VCO2N/P Pins
Active
3-state
5.6, “Carrier Synchronizer.”
3-47
6
5
4