Articles and news - 5

A previously published Design Idea describes a practical gadget that has the potential to save a lot with little investment. However, the circuit uses 120 V line voltage and, as such, it is not that convenient for many applications...

The circuit is designed for portable-power applications that require white LEDs with adjustable, logarithmic dimming levels. The circuit drives as many as four white LEDs from a 3.3 V source and adjusts the total LED current from 1 to 106 mA in 64 steps of 1 dB each...

When designing devices with microcontrollers, I like to use some of the analog-to-digital converter inputs to measure onboard voltages along with all the required sensors inputs. This means I often run out of ADC inputs...

A stable voltage from an input supply that is higher and lower than the output is often required. A common solution is to use a boost converter followed by an LDO...

There’s been a lot of interesting conversation and DI teamwork lately devising circuits for ON/OFF power control using inexpensive momentary-contact switches...

Dual precision comparators are needed in many designs, such as for industrial and instrumentation applications, to generate accurate pulse-width modulated waveforms with very high (>99%) and very low (<1%) duty-cycle percentages...

Injection locking can not only improve oscillator frequency stability and phase noise, but act as a selective frequency divider as well...

Frequent design idea contributor Nick Cornford recently published a synergistic pair of DIs... The main theme of these articles is design techniques for audio VCOs that have an exponential relationship between control voltage and frequency...

This modular resistor load bank uses a unique topology to reduce the number of switches and resistors while providing the maximum number of steps...

In general, muting and/or signal switching is done by relays, FETs or CMOS analogue switch ICs. All have limitations, but a little known technique that really doesn't look like it could ever work...