Quiescent current

FIGURE 7.52 The graphical solution to the push pull Class B amphfier configuration is shown. The quiescent point is midway between the ends of the loadline as in Class A, but unlike Class A, the quiescent current is zero. Each transistor output sees Ri at the collector since the center tapped primary transformer has a 1 1 turns ratio from Ri to each transistor even though it has a 2 1 primary (end to end) to secondary turns ratio. 

The next major category of testing is power supply current tests. Current tests include active switching current or power test, power down test, and standby or stable quiescent current tests. This last test, often called /ddq. wiU be discussed later. 

Quiescent current The current that flows in a device in the absence of an applied signal. 

Quiescent "current saving" method strobes LEDs 160+ Hz. To achieve <10% duty cycie to prolong battery life... 

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