ASM3P2183A

http://onsemi.com

2

Figure 1. Block Diagram

ModOUT

PLL

XIN/CLKIN

Crystal

Oscillator

SS%

FS0 FS1

VCO

Output

Divider

Loop

Filter

Phase

Detector

Modulation

Frequency

Divider

Feedback

Divider

XOUT

Table 1. 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 con-

nected 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 to 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 to 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 to Input Frequency and Modulation Rate Table). This pin has an internal

pull−up resistor.

Table 2. INPUT FREQUENCY AND MODULATION RATE TABLE

FS1 (pin 8)

FS0 (pin 7)

Frequency Range

0

0

6 MHz to 13 MHz

0

1

12 MHz to 25 MHz

1

0

25 MHz to 50 MHz

1

1

50 MHz to 90 MHz

Table 3. SPREAD DEVIATION SELECTION TABLE

SS% (pin 4)

Spread Deviation (%)

0

− 1.25

1

± 0.42