Connection Diagram

Pin Description

Pin

No.

Pin Name

I/O

Description

1

FoLD

O

Multiplexed output of the Main/Aux programmable or reference dividers and Main/Aux lock

detect. CMOS output. (See Programming Description 2.5)

2

OSC

IN

I

PLL reference input which drives both the Main and Aux R counter inputs. Has about 1.2V

input threshold and can be driven from an external CMOS or TTL logic gate. Typically

connected to a TCXO output. Can be used with an external resonator (See Programming

Description 2.5.4).

3

OSC

OUT

O

Oscillator output. Used with an external resonator.

4

GND

—

Aux PLL ground.

5

fin

AUX

I

Aux prescaler input. Small signal input from the VCO.

6V

CCAUX

—

Aux PLL power supply voltage input. Must be equal to V

3.6V. Bypass capacitors should be placed as close as possible to this pin and be

connected directly to the ground plane.

7

CPo

AUX

O

Aux PLL Charge Pump output. Connected to a loop filter for driving the control input of an

external VCO.

8EN

AUX

I

Powers down the Aux PLL when LOW (N and R counters, prescaler, and tristates charge

pump output). Bringing EN

9EN

MAIN

I

Powers down the Main PLL when LOW (N and R counters, prescaler, and tristates charge

pump output). Bringing EN

10

CPo

MAIN

O

Main PLL Charge Pump output. Connected to a loop filter for driving the control input of an

external VCO.

11

V

CCMAIN

—

Main PLL power supply voltage input. Must be equal to V

3.6V. Bypass capacitors should be placed as close as possible to this pin and be

connected directly to the ground plane.

12

fin

MAIN

I

Main prescaler input. Small signal input from the VCO.

13

GND

—

Main PLL ground.

14

LE

I

Load enable high impedance CMOS input. Data stored in the shift registers is loaded into

one of the 4 internal latches when LE goes HIGH (control bit dependent).

15

Data

I

High impedance CMOS input. Binary serial data input. Data entered MSB first. The last two

bits are the control bits.

16

Clock

I

High impedance CMOS Clock input. Data for the various counters is clocked in on the

rising edge, into the 18-bit shift register.

DS100129-2

Order Number LMX1600TM, LMX1601TM, or LMX1602TM

NS Package Number MTC16

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