Step-Up Converters Awake With Only 0.9V

In addition to operation from either 1- or 2-cell supplies, TK651xx series dc-to-dc converter/switching regulator ICs also can start up with a mere 0.9V. The devices take a dc input and raise it to a regulated 2.7V, 3.0V or 3.3V output, which is monitored by an internal comparator that provides a reset signal if the output falls below a specified minimum. The 6-pin SOT-23L step-up converters together with five components will provide up to 30 mA in single-cell applications, with the inductor value selected determining the maximum output current. The ICs also boast of low switching transients and laser-trimmed internal oscillator frequency. An application board configured for single-cell input and 3V, 4 mA output is also available.