AS1702 - AS1705
1.8W Single-Channel Audio Power Amplifiers
D a ta S he e t
1 General Description
The AS1702 - AS1705 are single-channel differential
audio power-amplifiers designed to drive 4 and 8Ω
loads. The integrated gain circuitry of these amplifiers
and their small size make them ideal for 2.7- to 5V-pow-
ered portable audio devices.
The differential input design improves noise rejection
and provides common-mode rejection. A bridge-tied
load (BTL) design minimizes external component count,
while providing high-fidelity audio power amplification.
The devices deliver 1.8W continuous average power per
channel to a 4Ω load with less than 1% total harmonic
distortion (plus noise), while operating from a single 2.7
to 5V supply.
For reduced component designs, the devices are avail-
able with different gain levels as shown in
Table 1. Standard Products
Model
AS1702
AS1703
AS1704
AS1705
Gain
Adjustable (via external components)
A
V
= 0dB
A
V
= 3dB
A
V
= 6dB
2 Key Features
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2.7 to 5.5V (V
CC
) Single-Supply Operation
THD+N: 1.8W into 4Ω at 1% (per Channel)
Differential Input
Adjustable Gain Option (AS1702)
Internal Fixed Gain to Reduce External Component
Count (AS1703, AS1704, AS1705)
<100nA Low-Power Shutdown Mode
Click and Pop Suppression
Pin-Compatible to National Semiconductor LM4895
(AS1705) and Maxim MAX9718A/B/C/D
Operating Temperature Range: -40 to +85ºC
Package Types
- 10-pin MSOP
- 10-pin DFN
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Integrated shutdown circuitry disables the bias genera-
tor and amplifiers, and reduces quiescent current con-
sumption to less than 100nA. The shutdown input can
be set active-high or active-low. All devices contain click-
and-pop suppression circuitry that reduces audible
clicks and pops during power-up and shutdown.
The AS1702 - AS1705 are pin compatible with the
LM4895 and the MAX9718A/B/C/D. The devices are
available in a 10-pin MSOP package and a 10-pin DFN
package.
Figure 1. Simplified Block Diagram
!
3 Applications
The devices are ideal as audio front-ends for battery
powered audio devices such as MP3 and CD players,
mobile phones, PDAs, portable DVD players, and any
other hand-held battery-powered device.
Single Supply 2.7
to 5.5V
9
V
CC
4
IN+
2
IN-
1
SHDN
3
SHDM
–
+
10
OUT+
R
L =
4 or 8Ω
6
OUT-
AS1702/AS1703/
AS1704/AS1705
7
GND
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