ISL99201
Filterless High Efficiency 1.5W Class D Mono Amplifier

Key Features

• Filterless class D with efficiency greater than 86% at 400mW
• Click-pop suppression
• Slew rate control
• Spread spectrum switching
• Optional SYNC pin for master/slave operation without interface
• 1.4W into 8W 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)

Description

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 8W load from a 5V supply.

The ISL99201 features a high-efficiency, low-noise modulation scheme. It operates with 86% efficiency at 400mW into 8W 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.

Applications

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