International Rectifier announced the introduction of the IR3847 high current Point-of-Load (POL) integrated voltage regulator that extends the current rating of IR's third generation SupIRBuck® family up to 25A in a compact 5x6 mm package.
As a result of a new thermally enhanced package using copper clip and several proprietary innovations in the controller, the IR3847 can operate at 25A without heat sink, and reduces PCB size by 20% compared to alternative integrated solutions and 70% compared to discrete solutions using a controller and power MOSFETs. A complete 25A power supply solution can be implemented in as little as 168 mm2.
The new device integrates IR's latest generation power MOSFETs with a feature-rich, third generation SupIRBuck® controller that includes post-package precision dead-time trimming to optimize losses, and internal smart LDO to optimize efficiency across the entire load range. True differential remote sense essential for high current applications, 0.5% reference voltage accuracy in 25°C to 105°C temperature range, input feed-forward and ultra-low jitter combine to enable total output voltage accuracy less than 3% over line, load, and temperature, as required by high performance communications and computing systems.
As part of the new Gen3 SupIRBuck single input voltage (5V-21V) family, the IR3847 features a proprietary modulator scheme that reduces jitter by 90% compared to standard solutions. This has the dual benefit of reducing output voltage ripple by approximately 30% and allowing higher frequency/higher bandwidth operation for smaller size, better transient response and fewer output capacitors.
Available in a compact 5x6 mm PQFN package, the IR3847 also offers electrical and thermal performance for 15A - 25A applications such as peak efficiency greater than 96% and temperature rise at 25A as low as 50°C. Other advanced features include external synchronization, sequencing, VTT tracking, and output voltage margining. The pinout is optimized for easy placement of bypass capacitors and the internal thermally compensated current limit offers three settings that allow programmability without extra components and layout complications.
The IR3847 offers the standard SupIRBuck features of switching frequency up to 1.5MHz, pre-biased start-up, input voltage aware enable, over voltage protection, power good, optional true output voltage sensing for open line feedback and adjustable OVP, internal soft-start and minimum input voltage of 1.0V (with ext. bias) and operating junction temperatures of -40oC to 125oC. The device is qualified for the industrial market.
Pricing for the IR3847M begins at US $2.23 each in 100,000-unit quantities. The IRDC3847 reference design can be purchased for US $29 per kit.
