P

A

4

4

0

1

C

l

i

c

k

-

P

o

p

S

u

p

p

r

e

s

s

i

o

n

D

e

v

i

c

e

PA4402

Click-Pop Suppression Device

ANALOG PRODUCTS DIVISION

2929 S Fair Lane, Tempe, AZ, 85282 Tel: (602) 431-8101. Fax: (602) 431-2288

www.protekdevices.com

95026. Rev.2. 02/2012

NOT FOR USE IN LIFE SUPPORT SYSTEMS

Pre

Amp

+

+

Pre

Amp

Pre

Amp

+

+

Pre

Amp

IN

OUT

IN

OUT

PRODUCT DESCRIPTION

Figure 2 shows the normal setup of a Pre Amplifier system. Since the system is built on a single ended power supply the outputs

of the pre-amplifier need to be routed through a bypass capacitor to get rid of the DC bias.

Figure 2: Normal setup for a pre amplifier output

When the power supply to the system is turned ON there is a spike in the output of the system because of the charging of

various components in the system. This spike is called a “Click or Pop Noise”. When this click/pop noise passes through the

Power Amplifiers, the noise is amplified and listen

ers hear an audible ‘pop’ which causing undesired noise. The reverse

operation happens when the system is powering down. The connection diagram is shown in Figure 3. The Powering Up

sequence is shown in Figure 4 and the Powering Down sequence is shown in Figure 5. The audible POP noise heard can be

caused by the powering up/down of the pre amp and/or CODEC devices. The PA4402 placed at the final output stage can

suppress these noises.

CONNECTION DIAGRAM

The PA4402 will be placed after the pre-amplifier and before the output bypass capacitors.

Figure 3: Typical Connection Configuration for PA4402