Transistor Outline-202:  National Semiconductor Application Note   (app note added 2/06)

Transistor Outline-226:  National Semiconductor Application Note   (app note added 2/06)

Transistor Outline-237:  National Semiconductor Application Note   (app note added 2/06)

Transistor Pair Lowers PWM IC's Start up Current:  03/18/99 EDN-Design Ideas / (added 6/06) An auxiliary winding usually provides power for the popular UC384X-based offline switch-mode power supplies (SMPSs). This winding feeds the main PWM controller during steady-state operation. However, the controller always needs a small start-up current, which clearly plagues the efficiency in very low-power standby SMPSs with POUT =500 mW, for example. Any wasted source power, such as for the start-up network and controller supply, adds to the power drawn from the mains and significantly degrades the overall efficiency. Obtaining an acceptable efficiency at high line voltage represents a tough design task. Some tricks totally stop the start-up current by using a high-voltage bipolar or MOSFET (Reference 1). However, the....

Transistor quickly wakes sleeping LDO:  09/01/98 EDN-Design Ideas / (added 110/05) Portable systems, such as telephone handsets, make extensive use of low-dropout (LDO) regulators. These components provide noise-sensitive parts with a stable power-supply line. When a telephone enters standby mode, most of the circuits go to sleep by disabling the LDO's outputs. Operating .....

Transistor Schmitt Trigger Oscillator:  The Schmitt Trigger oscillator below employs 3 transistors, 6 resistors and a capacitor to generate a square waveform. Pulse waveforms can be generated with an additional diode and resistor (R6). Q1 and Q2 are connected with a common emitter resistor (R1) so that the conduction of one transistor causes the other to turn off. Q3 is controlled by Q2 and provides the squarewave output from the collector. In operation, the timing capacitor charges and discharges through the feedback resistor (Rf) toward the output voltage. When the capacitor voltage rises above the base voltage at Q2, Q1 begins to conduct, causing Q2 and Q3 to turn off, and the output voltage to fall to 0. This in turn produces a lower voltage at the base of Q2 and causes the capacitor...   (added 11/05)

Transistor Spot Checker:  (schematic added 8/03)

Transistor tester fits into your pocket:  12/20/01 EDN Design Ideas  /  (added 1/05)  It can be helpful to rapidly and easily determine the polarity (npn or pnp) and function of a transistor. The pocket-transistor tester in Figure 1 is ideal for quickly testing without regard to such parameters as gain and frequency response. You connect the transistor, or device under test, between the collectors, T, of an astable multivibrator. ...

Transistor Trio Makes Vector Anemometer:  09/01/97 EDN-Design Ideas  / (added 8/03)  

Transistors offer overload delay:  09/16/04 EDN Design Ideas  / (added 11/05)  Although an SMPS (switch-mode power supply) can protect itself against permanent short circuits, it sometimes has problems when dealing with transient overloads. Transient overloads are not short circuits but can push the power supply above its nominal load value. This scenario occurs with typical loads such as printer heads and small motors.

Transistors offer thermal protection for Controller:  07)/19/01 EDN Design Ideas  /  (added 1/05)  When a switch-mode power-supply controller, such as On Semiconductor's NCP1200, operates at a high ambient temperature, you should protect the entire power supply against lethal thermal runaway. The NCP1200 operates directly from the power mains without an auxiliary winding; therefore, the die in the IC dissipates

Transistors tame perfidious leakage inductance:  09/27/01 EDN Design Ideas  /  (added 1/05)  In flyback converters that use primary regulation, the loose coupling between the power secondary and the primary auxiliary windings often results in poor cross-regulation. This situation arises mainly from the leakage inductance but also comes from the level of the primary clamp voltage. Figure 1 shows a typical application schematic using On Semiconductor's (www. ...

Two Transistor Amplifier #2:  (electronic circuit added 1/03)

Two Transistor Amplifier:  (schematic added 8/03)

Two Transistor Atomic Frequency Standard:  (circuit / schematic design added 6/06)

Two Transistor circuit replaces IC #1:  05/07)/2002  EDN Design Ideas / (added 10/03)    Linear Technology's recently introduced LTC4300 chip buffers I2C clock and data lines to and from a hot-swappable card. This task is difficult because the IC must work bidirectionally, meaning that you can simultaneously and actively drive both sides. However, as is sometimes the case, you can replace a complicated circuit by a simple one without much loss of performance. .

Two Transistor FM Transmitters:  (schematic added 8/03)

Two Transistor LED Flasher #1:  (schematic added 8/03)

Two Transistors Form Bidirectional Level Translator:  11/07)/96 EDN-Design Ideas / (added 8/03) Planar-magnetic technology is growing in popularity as a design option for dc-dc converters. In addition to providing electrical benefits, planar magnetics offers reduced leakage inductance and improved consistency. It also significantly reduces the cost of magnetics if you integrate it into the printed-circuit board. To use planar magnetics in a dc-dc converter, the switching frequency should be higher than 500 kHz. This high frequency limits the number of turns required for the magnetic element, thus making it easier to implement on the pc board.....

Ultra Low Voltage Crystal Oscillator Circuit using Active Loads:  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Low Voltage Differential Amplifier:  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Low Voltage Micropower Crystal Oscillator Circuit:  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Low Voltage Nanopower Inverter Circuit :  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Low Voltage Nanopower LC (Colpitts) Oscillator Circuit:  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Low Voltage Nanopower Two-Input NOR and NAND Gates:  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Low Voltage N-Channel Analog Switch (Transmission Gate):  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Low Voltage RC Oscillator :  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Ultra Miniature Surface Mount Transistor (2/17/94) :  Application Note California Eastern Laboratories Doc #906  (app note added 6/06)

Understanding MOSFET  Data:  Supertex Semiconductors  (app note added 2/06)

Understanding The Differences between Standard MOSFETs and Avalanche Energy Rated MOSFETs:  Application Note Microsemi-formerly Advanced Power Technology APT9402 ( app note added 4/08)

Unijunction Transistor:  The unijunction transistor (UJT) is a three terminal device with characteristics very different from the conventional 2 junction, bipolar transistor. It is a pulse generator with the trigger or control signal applied at the emitter . This trigger voltage is a fraction (n) of interbase voltage, Vbb. The UJT circuit symbol, junction schematic, and characteristic curve are ... (app note added 02/05)

Universal Power MOSFET  Interface IC (TC4420/9):  Microchip Application Note Published 14-Nov-02   (app note added 2/06)

Use of transil as rectifier diodes:  AN586  (app note added 6/06)

Using Surface Mount Power MOSFETs in Processor Power Supplies / AB-15:  Fairchild Application Notes / (app note added 3/06)

Various Transistor Throttle Circuits:  (circuit / schematic design added 6/06)

VDS(on) VCE(sat) Measurement:  Application Note Microsemi formerly Advanced Power APT0407) (added 05/07)

Video Amplifier Circuit from Discrete Transistors:  ASCII format (added 6/06)

Voltage Controlled Resistor:  Circuit Ideas for Designers Application Notes Advanced Linear Devices, Inc.  (app note added 6/06)

Voltage Reference improves JFET:  10/26/00 EDN-Design Ideas / (added 05/03) /The common JFET current-source in Figure 1a has average output impedance and depends heavily on the JFET's VP and IDSS variations. These manufacturing variations limit the initial accuracy of the current setpoint that the circuit can obtain with a fixed R1. Most users of JFET current-sources sample VP and IDSS for each lot of JFETs and then select R1 by first solving the quadratic equation ID=IDSS(1–VGS/VP)2 for VGS and then solving.....

ZTX415 Avalanche Mode Transistor: An Introduction to Characterisation, Performance and Applications:  Zetec Semiconductors  Applications Notes Avalanche mode switching operation of bipolar transistors is a useful but sometimes frustrating experience due to the lack of suitably designed components, and an understanding of their limiting values. The ZTX415 is the industry's first device that has been designed specifically for this function, and this note provides parametric background, typical application circuits, and also lists useful references.   (app note added 2/06)