600kHz, 1A Switch PWM DC/DC Converter

The LT1949 is a fixed frequency step-up DC/DC converter with a 1A, 0.5Ω internal switch. Capable of generating 10V at 175mA from a 3.3V input, the LT1949 is ideal for generating bias voltages for large screen LCD panels. Constant frequency 600kHz operation results in a low noise output that is easy to filter and the 30V switch rating allows output voltage up to 28V using a single inductor. An external compensation pin gives the user flexibility in optimizing loop compensation, allowing small low ESR ceramic capacitors to be used at the output. The 8-lead MSOP and SO packages ensure a low profile overall solution.

The LT1949 includes a low-battery detector that stays alive when the device goes into shutdown. Quiescent current in shutdown is 25µA, while operating current is 4.5mA.

Applications

* LCD Bias Supplies

* GPS Receivers

* Battery Backup

* Portable Electronic Equipment

* Diagnostic Medical Instrumentation

* 1.1A, 0.5Ω, 30V Internal Switch

* Operates with VIN as Low as 1.5V

* 600kHz Fixed Frequency Operation

* Low-Battery Detector Active in Shutdown

* Low VCESAT Switch: 410mV at 800mA

* Pin-for-Pin Compatible with the LT1317B

* Small 8-Lead MSOP Package and SO Packages