Product Specification

PE97632

Page 9 of 15

©2006-2011 Peregrine Semiconductor Corp. All rights reserved.

Document No. 70-0205-07 │ UltraCMOS™ RFIC Solutions

Functional Description

The PE97632 consists of a prescaler, counters,

an 18-bit delta-sigma modulator (DSM) and a

phase detector. The dual modulus prescaler

divides the VCO frequency by either 10 or 11,

depending on the value of the modulus select.

Counters “R” and “M” divide the reference and

prescaler output, respectively, by integer values

stored in a 20-bit register. An additional counter

(“A”) is used in the modulus select logic. The DSM

modulates the “A” counter outputs in order to

achieve the desired fractional step.

The phase-frequency detector generates up and

down frequency control signals. Data is written

into the internal registers via the three wire serial

bus. There are also various operational and test

modes and a lock detect output.

Figure 9. Functional Block Diagram

Control

Logic

Modulus

Select

10/11

Prescaler

M Counter

(9-bit)

R Counter

(6-bit)

Phase

Detector

R(5:0)

M(8:0)

A(3:0)

Sdata

Control

Pins

2 k



LD

Cext

DSM

+

Logic

PD_

U

PD_

D

K(17:0)