Chokeless Schmitt-trigger regulator

• US 3,983,472 A
• Filed: 03/11/1974
• Issued: 09/28/1976
• Est. Priority Date: 03/11/1974
• Status: Expired due to Term

• Current Assignee: Monroe Systems For Business, Inc. (Carolina Wholesale Office Machine Company, Inc.)
• Original Assignee: Litton Business Systems, Inc. (Baker Hughes Company)
• Inventors: Morris, David
• Primary Examiner(s): Pellinen, A. D.
• Application Number:
  US05/449,688
• Time in Patent Office: 932 Days
• Field of Search: 321/2, 321/18, 323/17, 323/22 T, 323/23, 323/25, 323/DIG. 1
• US Class Current: 323/271
• CPC Class Codes: H02M 3/3385 with automatic control of output voltage or current H02M3/33561 takes precedence

Abstract

A switching regulator is series connected to an oscillator. A schmitt trigger responds to load voltage variations to control the on-off conditions of the switching regulator. When the switching regulator is on the oscillator is on to provide through transformer coupling an output to a capacitor connected across the load. When the voltage across the capacitor increases to a predetermined value the schmitt trigger turns the switching regulator off and thereby the oscillator too, the capacitor continuing to discharge into the load.

Claims

1. An electrical power supply comprising:

first coupling means for coupling a direct current input voltage source;

second coupling means for coupling a regulated voltage to an output load;

schmitt trigger means having an input terminal, an output terminal, and a control terminal;

a storage capacitor directly coupled across said output load;

and non-conduction conditions, comprising a switching regulator means and an oscillator, said switching regulator means having an input terminal coupled to said first coupling means, a control terminal coupled to said output terminal of said schmitt trigger means, and an output terminal coupled to the input of said oscillator, the output of said oscillator coupled to the input of said storage capacitor, a switching amplifier means having conduction for switching said switching amplifier means to either a conduction or non-conduction condition, and for only allowing charging of said storage capacitor during said conduction condition; and

output voltage detector means having an input terminal coupled to said storage capacitor, and an output terminal coupled to said control terminal of said schmitt trigger means.

2. An electrical power supply according to claim 1 wherein said switching amplifier means also only allows said storage capacitor to discharge during said non-conduction period.

3. An electrical power supply according to claim 2 wherein said switching amplifier means comprises a rectifier circuit means, having an input and output, coupled at its input to the output of said oscillator and coupled at its output to the input of said storage capacitor.

4. An electrical power supply according to claim 2 wherein said switching regulator means comprises a series switching transistor having an input, output and control terminal.

5. An electrical power supply according to claim 4 wherein said schmitt trigger means comprises a schmitt trigger circuit having an output terminal and input terminal, said output terminal connected to said series switching transistor'"'"'s control terminal.