• 0.5V Negative Supply
  Although not very efficient, this simple circuit, consisting of two LEDs and a photo diode, generates a negative voltage with a current level of a couple milliamps.  It is ideal for supplying a negative rail to low power “rail to rail” op amp circuits, which need to have a true zero volts output.

• CHARGE PUMP EFFICIENTLY DIVIDES SUPPLY VOLTAGE
  This circuit uses a few FETs and logic devices to down convert a DC voltage to about one half its value

Buck Boost Regulator Suits Battery Operation - 09/04/03 EDN-Design Ideas: A buck/boost converter can step a voltage up or down. Such a converter is appropriate for battery-powered applications. One application derives a regulated 14.1V at 1A from 12V solar panels with 9 to 18V variation. In this type of battery application, efficiency is an important factor; hence, this design uses an inexpensive synchronous-rectifier-based MC33166/7 circuit.....(design idea added 1/05)

Charge Pump Efficiently Divides Supply Voltage  - This circuit uses a few FETs and logic devices to down convert a DC voltage to about one half its value ….(designed by David A. Johnson)

Circuit reduces negative Voltage stresses on Control IC - 04/18/02 EDN-Design Ideas: In a synchronous, buck switching power supply, the two FETS and the output inductor meet at the phase node (Figure 1). The phase node often connects directly to the control IC. The voltage on this node swings from the input voltage to some voltage lower than ground. If the voltage goes too far below ground, the ESD structures or other circuitry within the control IC can become forward-bia.....(design idea added 1/05)

Constant on time Buck boost regulator converts a positive input to a negative output - 12/07/04 EDN-Design Ideas: Buck regulators find wide application as step-down regulators for converting large positive input voltages into a smaller positive output voltages. Figure 1 shows a simplified buck regulator that operates in continuous-conduction mode—that is, the inductor current always remains positive. The output voltage, VOUT, is equal to D×VIN, where D is the duty-cycle ratio of the buck switc.....(design idea added 1/05)

Controlling Slew Times Tames EMI in Offline Supplies - 11/14/02 EDN-Design Ideas: EMI from offline switching power supplies typically causes all sorts of problems for power-supply designers. You may need a large EMI filter to meet FCC emission requirements. Switchers for high efficiency produce high-frequency switching noise that can propagate through the rest of the system and cause problems.....(design idea added 1/05)

DC to DC Controller Generates Negative Supply - 06/08/95 EDN-Design Ideas: a Switch mode Power Supply controller plus a diode capacitor network generate the modest negative Supply Current needed for OpAmps or for LCD Bias, without inductors.....(design idea added 7/02)

Depletion mode MOSFET kick starts power supply - 01/10/08 EDN-Design Ideas: A depletion-mode MOSFET virtually eliminates power wasted in switcher's start-up circuitry.....(design idea added 9/08)

Designing a Boost-Switching Regulator with the MCP1650 - Microchip Application Note Published 1-Apr-05  (app note added 2/06)

Eight Switcher Powers High Performance µPs - 04/13/95 EDN-Design Ideas: The circuit in Fig 1 delivers 8A for driving as many as two of today's high-performance, high-speed µPs. You can also optimize the design for lower current by changing a few components. Most systems use a low-current 12V bias supply and a poorly regulated high-current 5V to power the logic.....(design idea added 3/03)