Free electronic circuit design and schematic diagram
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 moreWe 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 moreThis is a circuit of Closed-Loop Automatic Power Control for RF Applications. The circuit uses a log detector (AD8318) and a VGA (ADL5330). This circuit has a high temperature stability because of the high temperature stability of the AD8318. The AD8318 also ensures the same level of temperature stability at the output of the ADL5330 VGA. The ADL5330 is converted […]
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This is a circuit of RC5 Infrared Remote Control Transmitter. This circuit uses The PCA8521 that when a key pressed, the PCA8521 generates It generates output pulses, in accordance with the RC5 protocol. Although the IC doesn’t contain a software programmable processor, it contain a ROM which can be used to store the codes that have to be transmitted. Here […]
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This is a infrared Remote Control Decoder circuit. This circuit uses the SAA3049A which is used to check and convert the received coded data (RECS80/RC5) into latched binary outputs. We can uses several device in one location because the device address can be hard-wired for a particular address. The output of this device are the received data and address. Here […]
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The best choice for stability and high accuracy in temperature measurements is Platinum resistance temperature detectors (RTD). However, the signal conditioning is complicated by the RTD which exhibit a non-linear temperature versus resistance characteristic. The non-linearity amount of 0 C to 100 C is up to 0.4 C. Here is the schematic diagram of linearized platinum RTD signal conditioner : […]
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Four phase drive signals for two phase bipolar and four phase unipolar step motors in microcomputer-controlled application is easily implemented using L29 Stepper Motor Controller IC. We can drive the motor in half step, normal and wave drives mode and switch-mode control of the current in the windings is permuted on chip PWM chopper circuits. This device has some features […]
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