| abstract |
A technique for controlling a power supply (70) with power supply controlnelement (82) with a tap element. In one embodiment, a power supply regulatornincludes a power transistor (88) having first, second, third and fourth terminals (89,n91, 93, 94). A control circuit (83) is included, which is coupled to the third andnfourth terminals (93, 94) of the power transistor (88). The power transistor (88) isnconfigured to switch a current between the first and second terminals (89, 91) innresponse a control signal received from the control circuit (83) at the third terminaln(93). A voltage between the fourth (94) and second terminals (91) of the powerntransistor (83) is substantially proportional to a current flowing between the first andnsecond terminals (89, 91) when a voltage between the first and second terminals (89,n91) is less than a pinch off voltage. The voltage between the fourth (94) and secondnterminals (91) of the power transistor is substantially constant and less than thenvoltage between the first and second terminals (89, 91) when the voltage between thenfirst and second terminals (89, 91) is greater than the pinch off voltage. |