A21SP16 Datasheet, PDF (1/37 Pages) STMicroelectronics – Thermal shutdown protection

A21SP16
3 W filter-free class-D audio power amplifier
Pin connection
IN₊
1/A1
GND
2/A2
OUT_-
3/A3
V_DD
4/B1
V_DD
5/B2
GND
6/B3
IN_-
STBY
OUT₊
7/C1
8/C2
9/C3
IN+: positive differential input
IN-: negative differential input
VDD: analog power supply
GND: power supply ground
STBY: standby pin (active low)
OUT+: positive differential output
OUT-: negative differential output
Block diagram
C2 ^Stdby Internal
Bias
150k
B1
B2
Vcc
Out+
C3
C1 _-
In-
In+ ₊
A1
PWM
Output
H
Bridge
150k
A3
Out-
Oscillator
GND
A2
B3
Features
 Operating from V_CC = 2.4 V to 5.5 V
 Standby mode active low
 Output power: 3 W into 4  and 1.75 W into 8 
with 10% THD+N max and 5 V power supply
 Output power: 2.3 W @ 5 V or 0.75 W @ 3 V
into 4 with 1% THD+N max
Datasheet - production data
 Output power: 1.4 W @ 5 V or 0.45 W @ 3 V
into 8 with 1% THD+N max
 Adjustable gain via external resistors
 Low current consumption 2 mA @ 3 V
 Efficiency: 88% typ.
 Signal to noise ratio: 85 dB typ.
 PSRR: 63 dB typ. @ 217 Hz with 6 dB gain
 PWM base frequency: 250 kHz
 Low pop & click noise
 Thermal shutdown protection
 Available in flip-chip 9 x 300 m (Pb-free)
Applications
 Wearable
 Fitness and healthcare
 Cellular phone
 PDA
Description
The A21SP16 is a differential class-D BTL power
amplifier. It is able to drive up to 2.3 W into a 4 
load and 1.4 W into a 8  load at 5 V. It achieves
outstanding efficiency (88% typ.) compared to
classical Class-AB audio amps.
The gain of the device can be controlled via two
external gain-setting resistors. Pop & click
reduction circuitry provides low on/off switch
noise while allowing the device to start within 5
ms. A standby function (active low) allows the
reduction of current consumption to 10 nA typ.
Part number
A21SP16
Table 1. Order codes
Temperature range
Package
-40 °C to +85 °C
Lead-free flip-chip
Packing
Tape & reel
Marking
62
March 2014
This is information on a product in full production.
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