Linear Technology Corp. provides high reliability versions of the LTC3803/-3/-5 current mode flyback controllers in the tiny 6-pin ThinSOT package. These devices are specified and are 100% production tested over a junction temperature range of -55 to 150°C. The input and output voltage ranges of LTC3803/-3/-5-based power supplies are limited only by external components, enabling wide-input-voltage and high-input-voltage applications.
The constant 200 or 300 kHz operating frequency is maintained down to very light loads, minimizing low frequency noise generation over a wide range of load current. An integrated soft-start function reduces inrush current and output voltage overshoot. A 100 mV current sense threshold allows the use of a small current sense resistor to maintain high efficiency. An LTC3803/-3/-5-based power supply does not require any minimum output load for stable operation. An internal shunt regulator allows the LTC3803/-3/-5 to be powered simply from a high input voltage through a series resistor. In wide-Vin-range applications where this isn’t feasible, the LTC3803 and LTC3803-3 feature a wide hysteresis undervoltage lockout that enables efficiency-enhancing micropower startup and bootstrap biasing techniques.