ISL99202IRTAZ Intersil, ISL99202IRTAZ Datasheet - Page 9

• Manufacturer Part Number: ISL99202IRTAZ
• Description: IC AMP STEREO 60MW 12-TQFN
• Manufacturer: Intersil
• Type: Class ABr

Specifications of ISL99202IRTAZ

• Output Type: Headphones, 2-Channel (Stereo)
• Max Output Power X Channels @ Load: 70mW x 2 @ 16 Ohm
• Voltage - Supply: 2.4 V ~ 5.5 V
• Features: Depop, Short-Circuit and Thermal Protection, Shutdown
• Mounting Type: Surface Mount
• Package / Case: 12-TQFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Typical Application Circuit
Detailed Description
The ISL99202 incorporates a novel proprietary architecture
to eliminate the large output capacitors associated with
single supply headphone amplifiers. Traditional charge
pump based architectures that eliminated the output
capacitors required additional power to operate the charge
pump, which made them ill-suited for portable battery
powered applications. The ISL99202 architecture eliminates
the need for large output capacitors while consuming
industry’s lowest quiescent and shutdown currents.
Capfree Architecture
At the core of the Capfree architecture is a dynamically
adjusted negative voltage regulator. By continuously
monitoring the output power requirements, it adjusts the
energy delivery circuitry. The feedback system ensures that
overhead power required to deliver audio at the headphone
speaker is always optimized for lower power dissipation.
Integrated LDO
A high precision LDO integrated into the power path of the
amplifier accounts for a 92dB PSRR. This eliminates the
need for a dedicated LDO used in some systems resulting in
BOM/cost savings.
Offset Cancellation Circuitry
The DC offset is a very important parameter. It is a principal
contributor to Click and Pop. In the cast Capfree
architecture, the DC offset can also be a source of DC
AUDIO INPUT
AUDIO INPUT
RIGHT
LEFT
9
1µ
1µ
INL
INR
ISL99202
ISL99202
+
-
-
+
current in quiescent state. The ISL99202 is tested and
trimmed to have very low offset voltages (typically 50µV).
RF Immunity
Most portable applications for ISL99202 are subject to RF
radiation from a myriad of sources, like Wi-Fi networks or
cellular phone networks. Though these signals are not in the
audio band, they can interfere with the audio signals through
complex non-linear mechanisms, aliasing or demodulations
to create audio band noise. The ISL99202 architecture
prevents this coupling into audio band to achieve superior
audio performance.
Protection Circuitry
The ISL99202 has comprehensive protection circuitry, which
protects the part due to undervoltage, over-temperature and
overcurrent. There is hysteresis built into over-temperature
and undervoltage, while the overcurrent is designed to limit
the output current in case of accidental short circuit or low
impedance headphone load connection.
References
Intersil Technical Brief 451: “PCB Assembly Guidelines for
Intersil Wafer Level Chip Scale Package Devices”
http://www.intersil.com/data/tb/TB451.pdf
Intersil Technical Brief 389: “PCB Land Pattern Design and
Surface Mount Guidelines for QFN Packages”
http://www.intersil.com/data/tb/tb389.pdf
OUTL
OUTR
May 29, 2009
FN6758.0