MC44824/25

2

MOTOROLA ANALOG IC DEVICE DATA

Representative Block Diagram

This device contains 3,204 active transistors.

Gnd

Test

Logic

Buffers

Latches

P–On

Reset

I2C Bus

Receiver

Latches

Phase

Comp

Ref

Divider

3.2 or 4.0

MHz Osc

Latch Control

Program Divider

15 Bit

Latches B

Latches A

Shift Register

15 Bit

÷8

Prescaler

Preamp

DTB2

POR

Operational

Amplifier

2.7 V

DTB1

CL

Data

RL

DTF

Fout

TDI

Fout

Fref

T10, T11

T9, T12, T14

T13

T8

4

7

9

(10)

8

(9)

(7)

6

(6)

14

(16)

10

(12)

5.0 V

Fout

Fref

13 (15)

7 (8)

4 (4)

5 (5)

11 (13)

CA

SDA

SCL

HF Input1

VCC

UD

PD

XTAL2

B7

B4

B2

B1

DTS, EN

512/1024

1 (1)

3 (3)

12 (14)

HF Input2

XTAL1

2 (2)

Gnd

(11)

B0

MC44825 Pin Numbers ( )

PIN FUNCTION DESCRIPTION

Pin

Sb l

Di

i

MC44824

MC44825

Symbol

Description

1

1

PD

Input of tuning voltage amplifier

2

2

XTAL1

First crystal input is the active pin at the oscillators

3

3

XTAL2

Second crystal input is the internal ground

4

4

SDA

Data input

5

5

SCL

Clock input of the I2C bus

6, 8, 9

–

B7, B2, B1

Band buffer (open collector) outputs for up to 10 mA

–

6, 7, 9, 10, 11

B7, B4, B2, B1, B0

Band buffer (open collector) outputs for up to 10 mA

7

8

CA

Chip address selection pin

10

12

VCC

Supply voltage, typical 5.0 V

11, 12

13, 14

HF1/HF2

Symmetric HF inputs from local oscillator

13

15

GND

Ground

14

16

UD

Output of the tuning voltage amplifier. Needs an external NPN with pull–up

resistor to drive the varicaps