Abstract: A pulsed diode light source driver includes a variable output power supply, an output capacitor, a switchable linear current driver, a temperature sensor, a conditioning circuit, and a voltage monitor. The temperature sensor monitors the temperature of the capacitor while the voltage monitor circuit monitors the output voltage level. The conditioning circuit and the voltage monitor cooperatively control the output voltage of the variable output power supply, so that temperature-related changes in the characteristics of the capacitor are compensated for, and a constant current is maintained through the diode load over a desired range of temperature. The driver is suitable for laser diodes and light emitting diodes.