Browse Prior Art Database

Transistor Switching Regulator Starting and Monitoring

IP.com Disclosure Number: IPCOM000052213D
Original Publication Date: 1981-May-01
Included in the Prior Art Database: 2005-Feb-11
Document File: 3 page(s) / 54K

Publishing Venue

IBM

Related People

Biamonte, A: AUTHOR [+3]

Abstract

This transistor switching regulator (TSR) has a starting and control circuit that stores sufficient energy in a capacitor to provide full power to the controls and power transistor for start-up while meeting See Original the additional regulation requirement to limit the rise of this voltage and consequent damage to the control circuits.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 3

Transistor Switching Regulator Starting and Monitoring

This transistor switching regulator (TSR) has a starting and control circuit that stores sufficient energy in a capacitor to provide full power to the controls and power transistor for start-up while meeting See Original the additional regulation requirement to limit the rise of this voltage and consequent damage to the control circuits.

The system is shown in block diagram form in Fig. 1. Fig. 2 defines the functions and the relative levels ("Limit Voltage", "Reset Point", etc.) of V(C) at which they occur. The capacitor C(C) is charged from the line via CR1 and R(1). The Hysteresis Switch 10, Protect Latch 12, and associated circuit functions draw their operating power from the voltage V(C), and load that voltage with current I(CH). By design, I(CH) is smaller than I(CR1), such that capacitor C(C)( will charge toward the peak of the line voltage. The control circuits, and in particular the transistor drivers, require large currents which would be expensive to obtain from the line directly; therefore, capacitor C(C) is charged with a very light current I(CR1). Capacitor C(C) stores sufficient energy to supply these larger currents.

Since neither I(CH) nor I(CR1) is particularly stable, V(C) could charge to a limit voltage approaching the peak of the input line voltage, resulting in damage to the control circuits. Therefore, a system is provided to roughly regulate V(C) between the maximum tolerable voltage and a minimum voltage required for full operation of the circuitry.

Switch 10 operates to turn on transistor T(1) when V(C) reaches the Turn On Point (defined in Fig. 2) and also to turn off transistor T(1) when V(C) drops to the Undervoltage. When switch 10 shuts off, that is, when T(1) is turned off, switch 10 also inhibits the pulsing of power Transistor T(2) and causes the latch 12 function to be set. Latch 12 is also set when V(C) climbs to the Overvoltage point. Latch 12 being set will inhibit circuit...