TS4621B
High-performance class-G stereo headphone amplifier
with I2C volume control
Features
TS4621BEIJT - flip-chip
■ Power supply range: 2.3 V to 4.8 V
■ 0.6 mA/channel quiescent current
■ 2.1 mA current consumption with
100 µW/channel (10 dB crest factor)
■ 0.006% typical THD+N at 1 kHz
■ 100 dB typical PSRR at 217 Hz
■ 100 dB of SNR A-weighted at G = 0 dB
■ Zero pop and click
Pinout (top view)
INR-
INR+
INL+
VOUTR
SCL
SDA
D
C
B
A
CMS
C2
PVSS
C1
2
■ I C interface for volume control
HPVDD
AGND
■ Digital volume control range from -60 dB to
+4 dB
INL-
4
VOUTL
3
AVDD
2
SW
1
■ Independent right and left channel shutdown
control
■ Integrated high-efficiency step-down converter
■ Low software standby current: 5 µA max
■ Output-coupling capacitors removed
■ Thermal shutdown
Balls are underneath
When powered by a battery, the internal step-
down DC/DC converter generates the appropriate
voltage to the amplifier depending on the
amplitude of the audio signal to supply the
headsets. It achieves a total 2.1 mA current
consumption at 100 µW output power (10 dB
crest factor).
■ Flip-chip package: 1.65 mm x 1.65 mm,
400 µm pitch, 16 bumps
Applications
THD+N is 0.02 % maximum at 1 kHz and PSRR
is 100 dB at 217 Hz, which ensures a high audio
quality of the device in a wide range of
environments.
■ Cellular phones, smart phones
■ Mobile internet devices
■ PMP/MP3 players
The traditionally bulky output coupling capacitors
can be removed.
Description
A dedicated common-mode sense pin removes
parasitic ground noise.
The TS4621B is a class-G stereo headphone
driver dedicated to high audio performance, high
power efficiency and space-constrained
applications.
The TS4621B is designed to be used with an
output serial resistor. It ensures unconditional
stability over a wide range of capacitive loads.
It is based on the core technology of a low power
dissipation amplifier combined with a high-
efficiency step-down DC/DC converter for
supplying this amplifier.
The TS4621B is packaged in a tiny 16-bump
flip-chip package with a pitch of 400 µm.
September 2011
Doc ID 022194 Rev 2
1/48
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