Connection Diagram

Pin Description

Pin

No.

Pin

Name

I/O

Description

1V

—

Power supply voltage input for RF analog and RF digital circuits. Input may range from 2.7V to

5.5V. V

pin and be connected directly to the ground plane.

2V

—

Power Supply for RF charge pump. Must be

≥ V

3D

O

Internal charge pump output. For connection to a loop filter for driving the input of an external

VCO.

4

GND

—

Ground for RF digital circuitry.

5f

I

RF prescaler input. Small signal input from the VCO.

6f

I

RF prescaler complementary input. A bypass capacitor should be placed as close as possible to

this pin and be connected directly to the ground plane. Capacitor is optional with some loss of

sensitivity.

7

GND

—

Ground for RF analog circuitry.

8

OSC

in

I

Oscillator input. The input has a V

or TTL logic gate.

9

GND

—

10

F

O

Multiplexed output of the RF/IF programmable or reference dividers, RF/IF lock detect signals

and Fastlock mode. CMOS output

(see Programmable Modes).

11

Clock

I

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

edge, into the 22-bit shift register.

12

Data

I

Binary serial data input. Data entered MSB first. The last two bits are the control bits. High

impedance CMOS input.

13

LE

I

Load enable high impedance CMOS input. When LE goes HIGH, data stored in the shift registers

is loaded into one of the 4 appropriate latches (control bit dependent(.

14

GND

—

Ground for IF analog circuitry.

15

f

I

IF prescaler complementry input. A bypass capacitor should be placed as close as possible to

this pin and be connected directly to the ground plane. Capacitor is optional with some loss of

sensitivity.

16

f

I

IF prescaler input. Small signal input from the VCO.

17

GND

—

Ground for IF digital, MICROWIRE, F

18

D

O

IF charge pump output. For connection to a loop filter for driving the input of an external VCO.

19

V

—

Power Supply for IF charge pump. Must be

≥ V

Thin Shrink Small Outline Package (TM)

DS012331-2

Order Number LMX2330ATM, LMX2331ATM or LMX2332ATM

NS Package Number MTC20

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