ISL54004 Datasheet, PDF (6/13 Pages) Intersil Corporation – Integrated Audio Amplifier Systems

ISL54004
ISL54004 Typical Application Circuit and Block Diagram
0.1µF
RIGHT AUDIO
LEFT AUDIO
0.22µF _INR
0.22µF _INL
GAIN
ROUTER/
SWITCHER
V_DD
BTL
SPK+
SPK-
HpR
SE
HD
HpL
SE
V_DD
100kΩ
10kΩ
HEADPHONE JACK
MICRO
CONTROLLER
CLICK
AND
POP
SD
HO
GSO
GS1
THERMAL ^BIAS
PROTECTION
REF ^CREF
1µF
LOGIC CONTROL
GND
Detailed Description
The Intersil ISL54004 device is an integrated audio power
amplifier system designed to provide quality audio, while
requiring minimal external components. Low 0.4% THD+N
ensures clean, low distortion amplification of the audio
signals. It is designed to operate from a single +2.7V to +5V
power supply. It is offered in a 20 Ld 4x4 TQFN package.
Targeted applications include battery powered equipment
such as cell-phones, MP3 players, and games/toys.
The ISL54004 part contains one class AB BTL type power
amplifier for driving an 8Ω mono speaker and two class AB
single-ended (SE) type amplifiers for driving 16Ω or 32Ω
headphones.
The BTL when using a 5V supply is capable of delivering
800mW (typ) with 0.4% THD+N and 941mW (typ) with 1%
THD+N of continuous average power into a stereo 8Ω BTL
speaker load. When the speaker load is connected across
the positive and negative terminals of the BTL driver the
voltage is doubled across the load and the power is
quadrupled.
Each SE amplifier when using a 5V supply is capable of
delivering 15mW (typ) with 0.07% THD+N and 50mW (typ)
with 0.3% THD+N of continuous average power into a 32Ω
headphone speaker.
When in Mono Mode (BTL driver active) the part automatically
mixes the left and right audio inputs and sends the combined
6
signal to the BTL driver. In Headphone Mode the right channel
input is sent to the right headphone speaker and the left
channel is sent to the left headphone speaker.
The ISL54004 features headphone sense input circuitry that
detects when a headphone jack has been inserted and
automatically switches the audio inputs from the mono BTL
output driver to the headphone drivers. It also has a logic
control pin (HO) that can override the sense input circuitry.
The ISL54004 has a four-level programmable gain stage to
boost the audio signal. The part requires no external gain
setting resistors. When GSO = GS1 = Low a driver will have a
gain of 1V/V (0dB). When GSO = High, GS1 = Low a driver
will have a gain of 1.2V/V (1.5dB). When GSO = Low,
GS1 = High a driver will have a gain of 2V/V (6dB). When
GSO = High, GS1 = High a driver will have a gain of 4V/V
(12dB). When the speaker is connected across the SPK+
terminal and SPK- terminal of the mono BTL driver you get an
additional gain of 2V/V (6dB) due to the BTL configuration.
The overall gain will be 2 times the values discussed above.
For example with GS1 = GS0 = High the overall gain will be
2 x 4 = 8V/V (18dB).
The part features low power shutdown, thermal overload
protection and click and pop suppression. The click and pop
circuitry prevents click and pops at the speakers when
transitioning in and out of shutdown.
FN6513.2
October 30, 2007