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 LT1308ACS8 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.
FeaturesLT1308Not Recommended For New DesignsLT1308AImproved Transient Response, Burst ModeLT1308BImproved Transient Response, Burst Mode DisabledFeature
- 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)
- Continuous Switching at Light Loads (LT1308B)
- Low VCESAT Switch: 300mV at 2A
- Pin-for-Pin Upgrade Compatible with LT1308
- Lower Quiescent Current in Shutdown: 1µA (Max)
- Improved Accuracy Low-Battery Detector Reference: 200mV ±2%
- Available in 8-Lead SO and 14-Lead TSSOP Packages
Applications
- GSM/CDMA Phones
- Digital Cameras
- LCD Bias Supplies
- Answer-Back Pagers
- GPS Receivers
- Battery Backup Supplies
- Handheld Computers
(Picture: Pinout)
