UPD17073 NEC, UPD17073 Datasheet - Page 135

• Manufacturer Part Number: UPD17073
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER WITH HARDWARE FOR DIGITAL TUNING SYSTEM
• Manufacturer: NEC

15.4 Phase Comparator ( -DET), Charge Pump, and Unlock FF
15.4.1 Configurations of phase comparator, charge pump, and unlock FF
frequency of the reference frequency generator, “f
charge pump, and unlock FF.
Figure 15-8 shows the configurations of the phase comparator, charge pump, and unlock FF.
The phase comparator compares the output frequency of the programmable divider, “f
The charge pump outputs the output signal of the phase comparator from the error out pin (EO).
The unlock FF detects the unlock status of the PLL frequency synthesizer.
The following paragraphs 15.4.2 through 15.4.4 respectively describe the operations of the phase comparator,
Reference frequency
Programable divider
Figure 15-8. Configurations of Phase Comparator, Charge Pump, and Unlock FF
generator
f
f
N
r
Phase comparator
( -DET)
r
”, and outputs UP or DW request signal.
PLL disable signal
DW
UP
Charge pump
Unlock FF
PLLUL flag
PD17072,17073
N
”, against the output
EO
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