Abstract: A switching circuit for switching an input dc voltage of predetermined polarity is used, for example, for a synchronous dc-dc converter. The switching circuit is divided between a high side package (52) and a low side package (56) each having a logic input (90) and a switch (6,8) connected between switching outputs (84,86). The switching outputs (84,86) of the high and low side packages (52,56) are connected in series between input voltage terminals (4,2). A pulse width modulator (18) is connected to the logic inputs (90) of the packages for supplying an alternating control signal for switching the high and low side switches (6,8) alternately. Each of the high and low side packages (52,56) contains logic circuitry (150) for controlling the respective switch (6,8) based solely on the voltages on the respective logic input (90) and respective switching outputs (84,86) to prevent the switches (6,8) in the high and low side packages (52,56) from conducting at the same time.

Abstract: A synchronous dc—dc converter converts an input dc voltage to an output dc voltage. A control FET (6) and a sync FET (8) are connected in series between input dc voltage terminals (2,4). An alternating control signal input from a control circuit (18) controls the control and sync FETs (6,8) to be switched on alternately. At least one driver (30, 32) is provided to drive the FETs (6,8). In response to a change in the alternating control signal of a predetermined polarity, the driver (32) switches off the sync FET (8), and then the driver (30) waits for the trigger signal before switching on the control FET (6).

Abstract: An integrated driver circuit includes a low side component and a synchronous dc voltage converter circuit. A sync FET (8) is controlled by a driver (32) powered between high and low voltage power connections (134, 138). A timing circuit (150) controls the driver circuit in accordance with a signal on a control input. The driver circuit (32) is isolated from the timing circuit (150), for example by a level shift circuit (136) and the low voltage power connection (138) of the driver circuit is directly connected to the source (108) of the sync FET (8). This arrangement is intended to reduce transient voltage effects.

Abstract: The invention relates to a low side component and a synchronous dc voltage converter circuit. A sync FET (8) is controlled by a driver (32) powered between high and low voltage power connections (134, 138). A timing circuit (150) controls the driver circuit in accordance with a signal on a control input. The driver circuit (32) is isolated from the timing circuit (150), for example by a level shift circuit (136) and the low voltage power connection (138) of the driver circuit is directly connected to the source (108) of the sync FET (8). This may reduce transient voltage effects.

Abstract: A synchronous dc-dc converter converts an input dc voltage to an output dc voltage. A control FET (6) and a sync FET (8) are connected in series between input dc voltage terminals (2,4). An alternating control signal input from a control circuit (18) controls the control and sync FETs (6,8) to be switched on alternately. At least one driver (30, 32) is provided to drive the FETs (6,8). In response to a change in the alternating control signal of a predetermined polarity, the driver (32) switches off the sync FET (8), and then the driver (30) waits for the trigger signal before switching on the control FET (6).

Abstract: A switching circuit for switching an input dc voltage of predetermined polarity is used, for example, for a synchronous dc-dc converter. The switching circuit is divided between a high side package (52) and a low side package (56) each having a logic input (90) and a switch (6,8) connected between switching outputs (84,86). The switching outputs (84,86) of the high and low side packages (52,56) are connected in series between input voltage terminals (4,2). A pulse width modulator (18) is connected to the logic inputs (90) of the packages for supplying an alternating control signal for switching the high and low side switches (6,8) alternately. Each of the high and low side packages (52,56) contains logic circuitry (150) for controlling the respective switch (6,8) based solely on the voltages on the respective logic input (90) and respective switching outputs (84,86) to prevent the switches (6,8) in the high and low side packages (52,56) from conducting at the same time.

Abstract: A dc—dc converter comprises first (5) and second (6) transistor switches connected in series between a dc input (1) and ground (4). The converter includes an inductor connecting the junction (8) of the two switches to a dc output and also a capacitor connecting the dc output to ground. The switches are closed alternately in response to a switching signal applied to a switching signal input (3), thereby alternately charging the capacitor from the dc input through the first switch and the inductor and discharging the energy stored in the inductor into the capacitor via the second switch. The coupling (12) from the switching signal input to the control input (25) of the second switch is provided with a threshold-responsive disable signal input (13) which is connected to the junction (8) between the two switches, for preventing the second switch from being controlled to a closed state at any time that the voltage on the junction is above a predetermined threshold.