Buck Converter Comes in Tiny Package

Jul 9, 2008 5:29 PM

Housed in a 1.26-mm by 1.56-mm micro SMD package, National Semiconductor’s LM3691 is a 4-MHz synchronous stepdown converter that provides up to 1 A of output. The converter is optimized for powering high-performance processors from a single Li-ion cell battery in mobile phones, personal media players and other mobile devices.

Device type: synchronous stepdown converter
Input voltage range: 2.3 V to 5.5V (fixed output)
Output voltage: 0.75 V to 1.8 V
Output voltage accuracy: ±1%
Output current: 1 A
Quiescent current: 490 μA in PWM mode, 64 μA typ. in ECO mode
Efficiency: peak efficiency of 95%
Features: switching frequency up to 4 MHz enables use of 1-μH multilayer inductors and 4.7-μF capacitors for a solution size of less than 15 mm2; load transient performance of ±40 mV (see the datasheet graphs starting on page 10); an integrated mode-control pin allows the design engineer to select forced PWM mode or auto mode, which changes modes between economy or ECO (gated PWM mode) and PWM automatically; overcurrent and overtemperature protection; a member of National’s PowerWise energy-efficient product family
Operating temperature range: -40°C to +125°C
Packaging: 6-pin, 1.26-mm by 1.56-mm micro SMD
RoHS compliant? yes
Target applications: single Li-Ion cell applications in mobile phones, personal media players and other mobile devices
Pricing: $2.25 each in 1000-unit quantities
Availability: available now
Data sheet posted on web? yes, see www.national.com/pf/LM/LM3691.html