Abstract

A voltage regulator (1) and includes a first switch (S1) coupled between an input conductor (2) and a first terminal (4) of an inductor (5), a second switch (S2) coupled between the first terminal of the inductor and a common conductor (3), a third switch coupled between an output conductor (7) and a second terminal (6) of the inductor, and a fourth switch (S4) coupled between the second terminal of the inductor and the common conductor (3). The voltage regulator is operated in a mixed buck-boost mode by producing a first signal (V32) representative of the difference between an output voltage (VOUT) produced on the output conductor (7) by the voltage regulator and a reference voltage. A second signal (IMEAS) is produced to represent the current through the inductor (5). A third signal (V68) is produced to represent a combination of the first signal and the second signal. A pulse width modulated error signal (PWM) is produced by comparing the third signal (V68) to a reference voltage. The first (S1) and fourth (S4) switches are controlled in response to the error signal (PWM) and first (Q23) and second (Q27) state signals representative of prior states of the first (S1) and fourth (S4) switches.

Other References

• "Dynamic Analysis of the Switch-Mode DC/DC Converters" by Andre Kislovski et al., Van Nostrand Reinold, New York, pp. 177-203, No dat