NCP2892 ON Semiconductor, NCP2892 Datasheet - Page 13

• Manufacturer Part Number: NCP2892
• Description: Audio Power Amplifier
• Manufacturer: ON Semiconductor

Gain−Setting Resistor Selection (R
NCP2892 should be used in low gain configurations.
values and maximizes the signal to noise ratio, and the
amplifier can still be used without running into the
bandwidth limitations.
recommended to optimize overall system performance.
of applications, and doesn’t require the use of a too large
capacitor C
Input Capacitor Selection (C
the amplifier input terminal. This capacitor creates a
high−pass filter with R
in low frequencies without severe attenuation. However a
fc
R
In order to optimize device and system performance, the
The low gain configuration minimizes THD + noise
A closed loop gain in the range from 2 to 5 is
An input resistor (R
The input coupling capacitor blocks the DC voltage at
The size of the capacitor must be large enough to couple
+
in
AUDIO
INPUT
2 * P * R in * C in
and R
in
f
1
set the closed−loop gain of the amplifier.
.
J9
J8
Figure 34. Schematic of the Demonstration Board of the 9−Pin Flip−Chip CSP Device
J3
V
.
in
p
in
) value of 22 kW is realistic in most
, the cut−off frequency is given by
100 nF
100 nF
C1
C5
150 kW
in
)
C2*
20 kW
20 kW
R1
R5
R3
in
100 kW
and R
1 mF
C3
R4
f
)
R2
100 kW
*C2, TP1: Not Mounted
BYPASS
SHUTDOWN
NCP2892 Series
INM
INP
http://onsemi.com
VM_P
13
V
large input coupling capacitor requires more time to reach
its quiescent DC voltage (V
turn−on pops when a single ended audio input is used.
performs well in many applications (With R
Bypass Capacitor Selection (Cby)
and determines how fast the NCP2892 turns on (see
Figure 21). With a differential audio input, the amplifier
will be a zero pop noise device no matter the bypass
capacitor.
critical component to minimize the turn−on pop. A 1.0 mF
bypass capacitor value (C
clickless and popless shutdown transitions. The amplifier
is still functional with a 0.1 mF capacitor value but is more
susceptible to “pop and click” noises.
p
An input capacitor value between 33 nF and 220 nF
The bypass capacitor Cby provides half−supply filtering
With a single ended audio input, this capacitor is a
Thus, a 1.0 mF bypassing capacitor is recommended.
1 mF
SHUTDOWN
CONTROL
+
+
−
−
C4
V
p
20 kW
20 kW
VM
OUTA
OUTB
in
J11
= < 0.39 mF) should produce
p
/2) and can increase the
J5
TP1*
V
J7
p
in
= 22 KW).
8W