| R (DC) | Only a resistor, used for DC circuits |
| T (DC) | Discrete constant current source, used for DC circuits |
| IC (DC) | IC constant current source, used for DC circuits |
| R+D (AC) | Resistor+Diode, the most simple AC circuits, low efficiency, very high power loss at high voltage |
| R+C+D (AC) | Resistor+Capacitor+Diode, a better AC circuit, can be used over a wide range of voltages |
| D+C+R (AC) | Diode+Capacitor+Resistor, best for low voltages, rectifies the voltage, this eliminates the mains frequence flashing of the LED |
| DD+CC+R (AC) | Dual diode+Dual capactir+Resistor, best for very low voltage, rectifies the voltage with a voltage doubler, this eliminates the mains frequence flashing of the LED |
| R+Bridge (AC) | Resistor+Bridge, double efficiency of a single diode |
| R+C+Bridge (AC) | Resistor+Capacitor+Bridge, the best AC circuit, can be used over a wide range of voltages with high efficiency |
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| Input voltage | Ac or DC voltage used to supply the circuit |
| Freq | Frequence of the AC voltage, when field is empty 50Hz is assumed |
| Led voltage drop | Volts accross LED while on, depends on LED type, check datasheet for actual LED, 2 volt can usual be used (for green/red/yellow leds) when the voltage drop over the resistor/capacitor is more than 3 volts |
| R | Voltage drop resistor, for series capacitor solutions this resistor is used to limit the peek current in the LED |
| C | Capacitor, this can be either series or parallel capacitor depending on circuit, be carefull with the voltage rating! |
| LED current | Design for specified current, most LEDS can handle 10mA, some LEDS can handle up to 30mA or more |
| Peek current | Worst case one time peek current (Vpp/R), usual in the range of 0.1 to 1A, a high peek current gives a good efficiency (Because most voltage is dropped accross the capacitor) |
| LED Ron | Dynamic on resistance of LED* |
| Diode Ron | Dynamic on resistance of diode* |
| Drop | Diode on voltage drop* |
| Bridge Ron | Dynamic on resistance of bridge* |
| Drop | Bridge voltage drop* |
| Transistor | Only visible when circuit T is shown, select transistor used in circuit |
| IC | Only visible when circuit IC is shown, select IC used in circuit |
* These values are used to make simple components models, when drawing the voltage waveforms, and calculate the
current/voltage/power of the components.
| Resistor | Designed resistor, remember to check the power rating |
| Discharge resistor | Optional capacitor discharge resistor. This resistor will discharge the capacitor to 50 volts in 1 second. This resistor is not included in the calculations. |
| Capacitor | Designed capacitor, remember to check the voltage. For mains connected circuits also be sure to use capacitors with the correct safety marking. |
| Diode/Bridge | A standard diode/bridge, check peek current rating and voltage rating |
| Current (rms) | RMS current in component |
| Current (peak) | Peak current in component, component must be able to withstand this current, for a short time, without fusing. |
| Voltage (rms) | RMS voltage over component |
| Voltage (peak) | Peak voltage over component, component must be able to withstand this voltage, for a short time, without damage |
| Power (rms) | Power dissipation in component |
| Power (peak) | Peak power dissipation in component, component must be able to withstand this power, for a short time, without damage |
| Peek (each cycle) | Peek current due to the AC frequence |
| Peek (one time) | Maximum peek current under worst case conditions: Capacitor charged to Vp, circuit switched in while supply is -Vp, giving Vpp accross the resistor |
| Peek falloff | How fast the one time peek disappears |
| Power input (rms) | Power used from supply |
| Power LED (rms) | Actuel power delivered to the LED |
| Efficiency | A low number means your have designed a heater |
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