Abstract: A boost DC-DC converter with a synchronous composite rectifier is presented. The boost DC-DC converter limits inductive in-rush current, includes a shutdown mode, operates also in step-down mode, and can be fabricated using conventional bipolar processes. The composite rectifier includes a power NPN transistor and a lateral PNP transistor. During converter start-up and in step-down mode (when the output voltage is less than the input voltage), the lateral PNP transistor drives the power NPN transistor. The lateral PNP transistor is biased such that inductive volt-second balance can be maintained, limiting in-rush current. In boost mode (when the output voltage is higher than the input voltage), the lateral PNP transistor is disabled and the power transistor is driven into saturation. Again, inductive volt-second balance can be maintained.

Abstract: An active pulldown means is provided for the output line of an ECL gate. The pulldown means utilizes a Wilson current mirror as a differential-to-single ended converter in a transition detection arrangement which tracks temperature variations and rejects supply voltage transients in order to ensure correct operation under all conditions. The desired and the present output conditions are compared in the detection scheme. High transient current is supplied to the output only when the two output conditions do not match for output high-to-low transitions.