Mutchus

BRIGHT FLASH FROM FLAT BATTERY This circuit can flash a white LED, on a provide from 2v to 6v and turn out a really bright flash. The circuit takes regarding 2mA and recent cells are often used. the 2 100u electros in parallel produce a much better flash when the availability is 6v. 3v WHITE LED FLASHER This will flash a white LED, on 3v provide and turn out a really bright flash. The circuit produces a voltage on top of 5v if the LED isn't in circuit however the LED limits the voltage to its characteristic voltage of three.2v to 3.6v.   The circuit takes regarding 2mA an is really a voltage-doubler (voltage incrementer) arrangement. Note the 10k charges the 100u. It doesn't illuminate the LED because the 100u is charging and also the voltage across it's invariably less than 3v. When the 2 transistors conduct, the collector of the BC557 rises to rail voltage and pulls the 100u HIGH. The negative of the 100u effectively sits just under the positive rail and also the positive...

Professional (directional) microphones often require a phantom supply of 48 V. This is fed via the signal lines to the microphone and has to be of a high quality. A portable supply can be made with 32 AA-cells in series, but that isn’t very user friendly. This circuit requires just four AA-cells (or five rechargeable1.2 V cells). We decided to use a standard push-pull converter, which is easy to drive and which has a predictable output voltage. Another advantage is that no complex feedback mechanism is required. For the design of the circuit we start with the assumption that we have a fresh set of batteries. We then induce a voltage in the secondary winding that is a bit higher than we need, so that we’ll still have a high enough voltage to drive the linear voltage regulator when the battery voltage starts to drop (refer to the circuit in Figure 1). T1 are T2 are turned on and off by an astable multivibrator. We’ve used a 4047 low-power multivibrator for this, which has been configu...

Infineon Technologies has launched an ultra-high ±5 cm resolution, miniature MEMS (Micro Electro Mechanical Systems) pressure sensor for use in mobile and wearable gadgets and IoT (Internet of Things) devices. The DPS310 is a low-power digital barometric pressure sensor that enables the development of new and enhanced navigation, location, well-being, gesture recognition and weather monitoring applications. Delivering accurate and stable performance across a wide temperature range, the DPS310 is ideal for indoor navigation and assisted location applications – such as floor detection in shopping malls and parking garages – and outdoor navigation where it can help to improve navigation accuracy or support ‘dead reckoning’ when GPS signal is not available. In addition, the ability to provide accurate data for calculating elevation gain and vertical speed suits activity tracking in mobile and wearable health and sports gadgets, while ultra-precise pressure measurement opens up new possibil...