Toshiba America Electronic Components, Inc. (TAEC) announced the launch of a new transistor output photocoupler in a low-height SO6L 4 pin package – the TLP385. With its low-height of 2.3 mm (max), 45 percent lower than DIP4 packages, the TLP385 can be used in situations with strict height requirements. Applications including motherboards, programmable logic controllers, AC adapters, I/O interface boards, inverter interfaces and general purpose power supplies are suited to the new photocouplers.
Toshiba’s new photocoupler has an isolation specification equivalent to DIP4 F (wide lead) type package products, and provides a creepage and clearance distance of 8 mm (min) and isolation voltage of 5 kVrms (min).
Toshiba Introduces New Low-Height Transistor Output Photocoupler - [Link]
by Jessica MacNeil @ edn.com:
What began as research to improve telephone service became one of the most important inventions in electronics history.
In 1945, AT&T’s research division, Bell Labs, began working on technology to replace vacuum tubes and make long-distance telephone service more reliable. William Shockley organized a solid-state physics group to research semiconductor replacements for vacuum tubes and electromechanical switches.
1st successful test of the transistor, December 16, 1947 - [Link]
by Susan Nordyk @ edn.com:
International Rectifier’s IRFH4257D is a 25-V dual N-channel power MOSFET housed in a 4×5-mm PQFN power-block package aimed at 12-V input DC/DC synchronous buck applications, such as telecom equipment, servers, graphic cards, and computers. With this latest power-block addition, designers now have the option of choosing a 4×5-mm or 5×6-mm PQFN to suit their design requirements.
Dual MOSFET squeezes into PQFN package - [Link]
by w2aew @ youtube.com:
This tutorial back-to-basics video discusses the operating point (or quiescent point, Q-point, bias point, etc.) of a bipolar transistor (BJT) circuit, and how the choice of the circuit design can affect how sensitive the bias point will be to the value of Beta (current gain) of the transistor. Ideally, you’d want to use a circuit which is completely independent of beta, so that a wide variety of transistors could potentially be used. Three different transistor bias circuits are demonstrated with three transistors, each with a different value of Beta. The current gain of the three transistors are measured and recorded, and then the resulting voltage ACROSS the collector resistors is measured for each transistor in each configuration. In other words the voltage between VCC and the collector is what is measured and recorded (not the collector voltage with respect to ground).
Bipolar Transistor bias circuits and Beta dependence - [Link]
by Suzanne Deffree @ edn.com:
Texas Instruments announced plans for the Regency TR-1, the first transistor radio to be commercially sold, on October 18, 1954.
The move was a major one in tech history that would help propel transistors into mainstream use and also give new definition to portable electronics.
TI was producing germanium transistors at the time, but the market had been slow to respond, comfortable with vacuum tubes.
However, the use of transistors instead of vacuum tubes as the amplifier elements meant that the device was much smaller, required less power to operate, and was more shock-resistant. Transistor use also allowed “instant-on” operation because there were no filaments to heat up.
TI announces 1st transistor radio, October 18, 1954 - [Link]
Kevin Rye writes:
I’m in the very early stages of prototyping a nixie clock. I picked up some MJE340 power transistors to switch on some IN-3s. I can then use a digital pin on my Arduino to turn on the IN-3s through the transistor. I’ll then have myself a blinking colon for my nixie tube clock.
Flashing a Nixie with an Arduino - [Link]
International Rectifier have announced the introduction of the IR66xx series of high performance 600V ultra-fast Trench-gate Field Stop insulated-gate bipolar transistors (IGBTs). The new high power family of devices features extremely low conduction and switching losses optimized for welding applications.
Utilizing Trench thin wafer technology to offer lowest conduction and switching losses, the new devices are co-packaged with a soft recovery low Qrr diode and feature ultra-fast switching (8 KHz – 30 KHz) with 5 µs short circuit rating. The 600 V IGBTs also feature low VCE(ON) and positive temperature coefficient for easy paralleling.
IR Launch Welding IGBT - [Link]
Open Analog is an organization dedicated to exciting makers about analog hardware. We make popular ICs into transistor level kits!
The first Open Source analog IC kit from Open Analog has been created, assembled, and verified. We call it the SevenFortyFun and it is a transistor level op amp kit. You can finally get the chance to understand whats going on inside those ICs! Now we need your help to proto the next revision (I gotta eat somehow!). This Kickstarter campaign is to raise money in order to print the first batch of PCBs and order parts for production volume.
741 Op-Amp Kit - [Link]
Analysis of the bipolar transistor amplifier at low-frequency is relatively easy, and several calculators exist online that do a good job. For high-frequency operation, there are fewer references available. For my projects, I like to build a reference spreadhseet where everything is in one place. This allows me more flexibility in optimizing the circuit, and is much faster than simulating with LTSpice or similar package. Furthermore, constructing such a tool is a great way of gaining more insight into how the circuit works, and how each of the parameters affects performance.
Common-Emitter and Common-Collector Transistor Amplifier Calculator for High-frequency Operation - [Link]
Electronics DIY published a new build, the Curious C-beeper:
Curious C-Beeper is a fun to build little probe that can be used to quickly detect the capacity of capacitors in pF nF range, test their stability with temperature changes, find broken wires, locate wires, trace wires on PCBs, and to locate live wires behind the walls without touching them. The circuit uses three transistors to make a most unusual capacitance beeper probe. When a capacitor is touched to the probe, the probe beeps at a frequency that varies with capacitance. The frequency change is so steep with capacitance that tiny capacitors may be precisely matched or an exact fixed value may be selected to replace a trimmer in a prototype.
Curious C-beeper - [Link]