Buck-Boost Charge Pump: LTC3245
Linear Technology Corp. announces a new high reliability MP-grade, wider temperature range version of the LTC3245, a versatile 250 mA high voltage buck-boost charge pump. The MP grade has an operating junction temperature range of -55° C to +150° C.
The LTC3245 uses switched capacitor fractional conversion to maintain regulation over a wide range of input voltage from 2.7 to 38 V and produces a regulated output of 3.3 V, 5 V or adjustable (2.5 to 5 V). Internal circuitry automatically selects a conversion ratio of 2:1, 1:1 or 1:2 to optimize efficiency as input voltage and load conditions vary. Low operating current (18 μA with no load, 4 μA in shutdown) and low external device count (three small ceramic capacitors and no inductors) make the LTC3245 ideally suited for low power, space constrained automotive/ applications such as ECU/CAN transceiver supplies, industrial housekeeping supplies and efficient low power 12 to 5 V conversion.
The LTC3245’s unique constant frequency architecture with reduced switching edge rates provides lower conducted and radiated noise compared to conventional switching regulators. The device has pin selectable Burst Mode® operation, enabling the user to trade off low output ripple for better efficiency and lower quiescent current. Other features include low external parts count with ceramic capacitor stability, soft-start circuitry to prevent excessive current flow during startup, plus short circuit and thermal protection.
Summary of Features: LTC3245 – MP Grade
- 2.7V to 38V VIN Range
- Operating Junction Temperature Range: -55°C to +150°C (MP Grade Only)
- IQ = 18µA Operating; 4µA in Shutdown
- 12V to 5V Efficiency = 81%
- Multimode Operation (2:1, 1:1, 1:2) with Automatic Mode Switching
- Low Noise, Constant Frequency Operation
- IOUT = 250mA (Maximum)
- Pin-Selectable Burst Mode® Operation
- VOUT: Fixed 3.3V, 5V or Adjustable
- Over-Temperature & Short-Circuit Protection
- Thermally Enhanced 12-Pin MSOP Package
The LTC3245 MP grade is available in a compact 12-lead MSOP package with a backside thermal pad. 1000-piece pricing starts at $7.55 each and devices are available from stock. For more information, visit Linear's web site.