Latch-up in bipolar low-voltage current sources

Latchup prevention is one general design problem of bipolar circuits able to operate at supply voltages of 1 V or even less. A method to solve this problem, using simple means to force saturation of some chosen transistors, is discussed. This method is demonstrated for application in low-voltage current sources. Conditions for a latchup-free design for various types of circuits and load-current situations have been derived and tested.