Low Drop-Out (LDO) Voltage Regulator Using Discrete Semiconductors

There are several integrated circuit chips designed specially for LDO (low drop out) voltage regulator. Building LDO using standard op-amp and discrete components can be an alternative. Here is one design of LDO circuit: Here some guidelines to select the components values: D1 is chosen for the best performance, the sharper the on-off transition curve the better. Some people say […]

Read more

Audio Amplifier with DC Volume Control

The TDA7052B and TDA7052BT are 0.5 W and 1 W mono Bridge-Tied Load (BTL) output amplifiers with DC volume control. Not only have been designed for use in TV and monitors, but TDA7052B and TDA7052BT are also suitable for use in battery-fed portable recorders and radios. This devices are integrated with a Missing Current Limiter (MCL). When the difference in […]

Read more

Fan Speed Controller Using Op-Amp

We can make an enhancement to DAC drive fan controllers with the use of an external amplifier that closes the loop around the tachometer. Essentially linear control over the full range of 8 bit DAC codes from 0 to 255 is provided by this enhancement. This only requires a little signal conditioning and a suitable amplifier arrangement since the tachometer […]

Read more

MAX6650 Fan Speed Controller

We can simplified greatly the fan speed regulation design using a dedicated IC such as the MAX6650 or MAX6651. The MAX6650 is designed to control a single fan. The MAX6651 has more features, it can controls a single fan and can monitor and watchdog three additional fan tachometer outputs. We can synchronize multiple MAX6651s to control multiple fans. The IC […]

Read more

VHF (100-450 MHz) 250W Power Amplifier

Two octave wideband amplifier (covering both the civil and military airbands between 100 and 450 MHz), equipped with two MOSFET devices, which is capable of generating 250 W of output power are given on this design procedures and measurement results report. One of the two octave wideband amplifier has to use the device s with the output capacitance reduced to […]

Read more

Analog Multiplier

The figure below shows a simple embodiment of the analog multiplier. This circuit provides three quadrant analog multiplication which is relatively temperature insensitive and which is not subject to the bias current errors which is plague most multipliers and circumvents many of the problems associated with the log-antilog circuit. By considering A2 as a controlled gain amplifier, amplifying V2, whose […]

Read more

Adjustable High Power LED Driver

A circuit that can drive three to four high power LEDs is shown on figure below. The ADP 1610 is an adjustable boost regulator. The voltage headroom and current for the LEDs is provided by this device. An average gain of 12 feedback network that servos the Rset voltage and the ADP1610 FB pin 1.2 V band gap reference voltage […]

Read more
1 26 27 28 29 30 33