United States Patent
US Patent 5157347: Switching bridge amplifier
US 5157347 ยท granted 1992-10-20
Abstract
Bridge amplifier circuit including a linear amplifier stage (3) which in single-ended configuration drives a load (13). Once the output voltage (U.sub.0) at the output (7) of the amplifier stage (3) has reached the maximum or minimum output swing limit, the voltage on the load terminal (14) remote from the output (7) is either reduced or increased by a switch circuit (15) in response to control signals (36) originating from control means (37) in dependence on the input signal (U.sub.i) and/or the output signal (U.sub.0). The switch circuit (15) includes a bidirectional switch (16) arranged as two controllable diodes (90, T.sub.11) connected in anti-parallel and having very little forward bias. Compensating voltage jumps at the output (7) of the amplifier stage (3), which require a high slew rate, are avoided in this manner.
| Patent Number | 5157347 |
|---|---|
| Title | Switching bridge amplifier |
| Filed | 1992-01-17 |
| Granted | 1992-10-20 |
| Inventor(s) | Boezen; Hendrik, Geerdink; Lambertus H. |
| Assignee | U.S. Philips Corporation |
| Number of Claims | 38 |
Abstract
Bridge amplifier circuit including a linear amplifier stage (3) which in single-ended configuration drives a load (13). Once the output voltage (U.sub.0) at the output (7) of the amplifier stage (3) has reached the maximum or minimum output swing limit, the voltage on the load terminal (14) remote from the output (7) is either reduced or increased by a switch circuit (15) in response to control signals (36) originating from control means (37) in dependence on the input signal (U.sub.i) and/or the output signal (U.sub.0). The switch circuit (15) includes a bidirectional switch (16) arranged as two controllable diodes (90, T.sub.11) connected in anti-parallel and having very little forward bias. Compensating voltage jumps at the output (7) of the amplifier stage (3), which require a high slew rate, are avoided in this manner.
Claim 1
Switching bridge amplifier comprising: an amplifier stage having an input for receiving an input signal to be amplified, and having an output for presenting an output voltage which varies in a positive and a negative sense relative to a reference voltage; a reference voltage terminal for connecting a reference voltage source for a reference voltage supply; first and second load terminals for connecting a load, the first load terminal being coupled to the output of the amplifier stage; a plurality of at least one positive switch voltage terminals, for connecting respective positive switch voltage sources to respective switch voltages which, in ascending steps deviate in a positive sense from the reference voltage; a plurality of at least one negative switch voltage terminals, for connecting respective negative switch voltage sources to respective switch voltages which, in ascending steps deviate in a negative sense from the reference voltage; switch means comprising a reference switch, a number of positive switches corresponding to the plurality of positive switch voltage terminals, and a number of negative switches corresponding to the plurality of negative switch voltage terminals
Claims
38 totalSwitching bridge amplifier comprising: an amplifier stage having an input for receiving an input signal to be amplified, and having an output for presenting an output voltage which varies in a positive and a negative sense relative to a reference voltage; a reference voltage terminal for connecting a reference voltage source for a reference voltage supply; first and second load terminals for connecting a load, the first load terminal being coupled to the output of the amplifier stage; a plurality of at least one positive switch voltage terminals, for connecting respective positive switch voltage sources to respective switch voltages which, in ascending steps deviate in a positive sense from the reference voltage; a plurality of at least one negative switch voltage terminals, for connecting respective negative switch voltage sources to respective switch voltages which, in ascending steps deviate in a negative sense from the reference voltage; switch means comprising a reference switch, a number of positive switches corresponding to the plurality of positive switch voltage terminals, and a number of negative switches corresponding to the plurality of negative switch voltage terminals