Standby Circuit for Power Savings
Original Publication Date: 1986-Sep-01
Included in the Prior Art Database: 2005-Mar-09
Power is saved by disabling a reference voltage so that all of the current sources drawing current from the power supplies are disabled. The CCSL (cascode current switch logic) of all the head driver circuits of a resistive ribbon typewriter, for example, employ a reference circuit providing a bias voltage from which all the current sources of the chip are derived. The head driver is not needed when a user is keying the display and during line feed and tab operations, so that turning off the power at such times will save power. A reference circuit 1 (Fig. 1) produces a VREF LOW signal on a line 2 and a VREF HIGH signal on a line 3. The VREF LOW signal is utilized as a reference signal to activate a plurality of useful circuits 4, which could be other than parts of head driver circuits of a resistive ribbon typewriter.