JSMSEMI IRS20957STR-JSM

The IRS20957 is a high-voltage, high-speed MOSFET driver with floating PWM input, designed for Class D audio amplifier applications. It integrates high- and low-side overcurrent protection (for both high- and low-side power devices), shoot-through prevention dead-time logic, and three voltage domains (VDD~VSS / VCC~COM / VB~VS).

Without any external shunt resistors, the IRS20957's bidirectional current sensing capability detects overcurrent conditions during both positive and negative load current cycles. A built-in protection control module provides safe protection sequencing and a programmable reset timer for overcurrent conditions.

An internal dead-time generation module enables precise gate switching control and optimal dead-time settings for improved audio performance, including lower THD and reduced audio noise.

The IRS20957 is a high-power Class D audio amplifier driver IC with integrated overcurrent protection. Combined with an error amplifier, two external power MOSFETs, and passive components, it forms a complete Class D audio power amplifier with high- and low-side overcurrent protection, shoot-through protection, and undervoltage lockout. Overcurrent detection is achieved by sensing the power MOSFET's Rds(on), eliminating the conventional direct current sensing approach, simplifying the system architecture, and reducing application complexity. To accommodate a bridge output topology, the analog PWM input and protection logic are placed in a floating well, as is the high-side circuitry. The breakdown voltage between the floating well and the chip substrate ground (COM) exceeds 200V, enabling use in power amplifier applications up to ±100V with output power exceeding 500W.

• Floating PWM input
• Integrated overcurrent protection with auto-recovery on both high-side and low-side
• External 5V reference voltage output; programmable low-side overcurrent protection threshold
• Programmable preset dead time for improved THD performance
  • 15ns @ DT pin voltage > 0.57V
  • 25ns @ 0.57V > DT pin voltage > 0.36V
  • 35ns @ 0.36V > DT pin voltage > 0.23V
  • 80ns @ 0.23V > DT pin voltage > 0V
• High transient noise immunity (CMTI): > 50V/ns
• Output swing up to ±100V, enabling output power exceeding 500W
• 3.3V/5V logic-compatible input
• Maximum operating frequency up to 800kHz
• Wide temperature range: -40°C~125°C
• Switching parameters:
  • 90ns/105ns typical propagation delay
  • 500ns maximum overcurrent protection delay
  • 250ns maximum enable control delay
• Output source/sink current capability up to 2A
• RoHS compliant
• SOP-16

• Home theater systems
• Stereo systems
• Mini component systems
• Active speaker systems
• General-purpose audio power amplifiers