Single Cell High Current Micropower 600kHz Boost DC/DC Converter

The LT1308A/LT1308B are micropower, fixed frequency step-up DC/DC converters that operate over a 1V to 10V input voltage range. They are improved versions of the LT1308 and are recommended for use in new designs. The LT1308A features automatic shifting to power saving Burst Mode operation at light loads and consumes just 140µA at no load. The LT1308B features continuous switching at light loads and operates at a quiescent current of 2.5mA. Both devices consume less than 1µA in shutdown.

Low-battery detector accuracy is significantly tighter than the LT1308. The 200mV reference is specified at ±2% at room and ±3% over temperature. The shutdown pin enables the device when it is tied to a 1V or higher source and does need to be tied to VIN as on the LT1308. An internal VCC clamp results in improved transient response and the switch voltage rating has been increased to 36V, enabling higher output voltage applications.

The LT1308A/LT1308B are available in the 8-lead SO and the 14-lead TSSOP packages.

Features

LT1308

Not Recommended For New Designs

LT1308A

Improved Transient Response, Burst Mode

LT1308B

Improved Transient Response, Burst Mode Disabled

Applications

* GSM/CDMA Phones

* Digital Cameras

* LCD Bias Supplies

* Answer-Back Pagers

* GPS Receivers

* Battery Backup Supplies

* Handheld Computers

* 5V at 1A from a Single Li-Ion Cell

* 5V at 800mA in SEPIC Mode from Four NiCd Cells

* Fixed Frequency Operation: 600kHz

* Boost Converter Outputs up to 34V

* Starts into Heavy Loads

* Automatic Burst Mode™ Operation at Light Load (LT1308A)