Free Simple Circuit Diagram
When you design a circuit with only a single-cell battery, you will need boost-converter to provide enough voltage for most application. This circuit is a modification of the diode-OR connection circuit. The linear regulator is formed by the U1’s internal gain coupled with the PFET(Q1). The diode-OR connection is connected to Q1’s source that will act as USB power supply. […]
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A LM3900 quad operational amplifier can be used to build a pulse width (PWM) controller. The LM3900 was chosen because it only need single supply voltage of 4 to 30 V. This circuit can give 100 percent pulse-width control. A1 op-amp forms a 1 kHz oscillator, generating a square wave oscillator for the basic oscillation. A2 is a ramp generator […]
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We can do a step-up conversion without using transformer. Using this circuit, a 5V DC source can be converted into 15V. Please note that there is no power gain here, as we cannot create energy from nothing, it means that we can leverage the voltage but the current will drop. This circuit can provide 15V source but the maximum current […]
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A DC to DC converter is needed for a board that only has +5V supply but have to provide dual-polarity supplies for few device such as op-amp or some DAC. Using switched capacitors as the main converting element (diode-capacitor voltage-doubler), there is no inductors or transformers in this circuit. This circuit also does not require dc-to-dc converter ICs but uses […]
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