The ISL99201 is a fully integrated high efficiency class-D
mono amplifier. It is designed to maximize performance for
mobile phone applications. The application circuit requires a
minimum requirement of external components and operates
from a 2.4V to 5.5V input supply. It is capable of delivering
1.4W of continuous output power with less than 1% THD+N
driving a 8Ω load from a 5V supply.
The ISL99201 features a high-efficiency, low-noise
modulation scheme. It operates with 86% efficiency at
400mW into 8Ω and has a signal-to-noise ratio (SNR) that is
better than 95dB. The ISL99201 has a micro-power
shutdown mode with a typical shutdown current of 200nA.
Shutdown is enabled by applying a logic low to the SD pin.
The architecture of the devices allows it to achieve very low
level of pop-and-click. This minimizes voltage glitches at the
output during turn-on and turn-off, thus reducing audible
noise on activation and deactivation.
The fully differential input of the ISL99201 provides excellent
rejection of common mode noise on the input typically 75dB.
EMI suppression is achieved by SRC (Slew Rate Control).
The ISL99201 oscillator can be synchronized to an external
clock through the SYNC input, allowing the switching
frequency to be externally defined. The SYNC input also
allows multiple ISL99201 to be cascaded and frequency
locked; minimizing interference due to clock intermodulation.
The ISL99201 also has excellent rejection of power supply
noise, including noise caused by GSM transmission bursts
and RF rectification. PSRR is typically 75dB at 217Hz. There
will be 4 versions of the part; they will consist of three fixed
gain settings (6dB, 9. 6dB, 12dB) and one user
programmable gain setting (need external resistors).
The ISL99201 has built-in thermal shutdown and output
short-circuit protection.

Features
• Filterless class D with efficiency > 86% at 400mW
• Click-pop suppression
• Slew rate control
• Spread spectrum switching
• Optional SYNC pin for master/slave operation without
interface
• 1.4W into 8Ω with less than 1% THD+N
• 2.4V to 5.5V single supply voltage
• Built-in resistors to reduce board component count
• Only one external component required (Fixed gain mode)
• Short circuit and thermal protection
• Gain programmable 6dB, 9.6dB, 12dB and User
programmable
• Pb-Free (RoHS compliant)

Applications
• Mobile phones
• MP3 players
• Portable gaming
• Portable electronics
• Educational toys