March 2007

ASM3P2183A

rev 1.7

EMI Reduction IC

2 of 8

Notice: The information in this document is subject to change without notice.

Block Diagram

Pin Configuration

Pin Description

Pin#

Pin Name

Type

Description

1

XIN /CLKIN

I

Crystal connection or external frequency input. This pin has dual functions. It can

be connected to either an external crystal or an external reference clock.

2

XOUT

I

Crystal connection. Input connection for an external crystal. If using an external

reference, this pin must be left unconnected.

3

P

Ground to entire chip.

4

SS%

I

Spread range select. Digital logic input used to select frequency deviation

(Refer Spread Deviation Selection Table). This pin has an internal pull-up resistor.

5

ModOUT

O

Spread spectrum low EMI output.

6

P

Power supply for the entire chip.

7

FS0

I

Frequency range select. Digital logic input used to select frequency range

(Refer Input Frequency and Modulation Rate Table). This pin has an internal

pull-up resistor.

8

FS1

I

Frequency range select. Digital logic input used to select frequency range

(Refer Input Frequency and Modulation Rate Table). This pin has an internal

pull-up resistor.

XIN /CLKIN

Crystal

Oscillator

Frequency

Divider

Feedback

Divider

Modulation

Phase

Detector

Loop

Filter

VCO

Output

Divider

ModOUT

PLL

SS%

FS0

FS1

XOUT

1

2

3

4

5

6

7

8

FS1

ModOUT

XIN / CLKIN

XOUT

SS%

FS0

ASM3P2183A