Best-in-class voltage regulator for high performance communications and computing applications
International Rectifier (IR) 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 5×6 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 heatsink, 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 168mm2.
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.
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| IR3847 Basic Application Circuit |
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 5×6mm PQFN package, the IR3847 also offers market-leading 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.
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| Efficiency [Vin=12V, Fsw=600kHz] |
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 –40°C to 125°C. Finally, it is qualified for the industrial market.
Specifications
|
Part Number
|
Package
|
Circuit
|
VIN Range
(V) |
VOUT Range
(V) |
IOUT
(A) |
Switching
Frequency (kHz) |
|
IR3847MTRPbF
|
PQFN
5×6mm |
Single Output
|
1 – 21V
|
0.6 – 86%Vin
|
25
|
300 -1,500
|
Design Tools
A datasheet and application notes are posted on the International Rectifier website at www.irf.com. The IRDC3847 reference design featuring the new device is also available.
|
Reference
Design |
Featured
Part |
VIN
(V) |
VOUT
(V) |
IOUT
(A) |
Switching Frequency
(kHz) |
|
IRDC3847
|
IR3847M
|
12
|
1.2
|
25
|
600
|
Price and Availability
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.
