87 LEDs in parallel what type of rectifier diode is suitable

It is better to use a low dropout voltage regulator, and the voltage drop is less than 1V

As long as you use a group of four LEDs to limit the current limiting resistors, use the same groups in parallel and then connect them to 12V, without any diodes.

Are you doing a LED light that flashes with **, it is not called a rectifier diode, it is called a switch diode, and it is not a step-down. It's OK to connect the sound output, but the effect is not good.

The rectifier diode can not reduce the voltage from 12V to 2V, and 12 LED lights can be connected to the battery in series, and if they are not bright enough, they can be less than 1.

The voltage drop of the rectifier diode can be done with two 1N4007 rectifier diodes of 1A. The IN5404 rectifier diode is recommended for more durability. Some regulators are sold.

It depends on whether you can buy it or not. Connect 8 to 10 of that kind of LED light-emitting two-section tube, light-emitting two-section tube yes. The 8 LEDs are only used in parallel.

Add a few ohms of resistance and you're good to go.

It mainly depends on how much A you need when the current. 1A chooses 1N4001, 2A chooses 1N5401

It is enough to choose two silicon diodes in series, such as 1N4007, etc.

The selection of this parameter is the same as the requirements of the switching power supply, it is difficult to explain clearly on this, it is recommended to refer to the relevant books of the switching power supply, which have a detailed description of the selection of component parameters.

From a technical point of view: under the premise of requiring normal luminescence, how much voltage is needed for a single connection, how much voltage is needed for parallel connection.

In series, the number of single voltages can be used.

The key is in the control of the current.

However, now many drive power supplies, is constant current, the voltage can be automatically adjusted to the best state, according to the calculation of each LED 3V, 5 is 15V, 20 is 60V, but I have used the same driver to bring 2 beads - 20 beads (F5, that is, 5 mm lamp beads) can be used normally and for a long time, so the driver only needs to choose the appropriate current.

The 5WLED bulb itself has a full-wave rectifier circuit, there is no need to add a rectifier diode, if it is used as a step-down, only a rectifier diode is not useful, because there are more than 10 diodes in series, and the step-down mainly depends on its step-down capacitor.

Reverse voltage means that the reverse voltage should not exceed 5V, which will be damaged after exceeding, and this situation will not occur with normal connection.

Two in parallel connected with 3V voltage (to ensure that the current is sufficient), in series with 6V

If the mains is a standard sine wave, then there is no need for these capacitors, but unfortunately our mains is not a standard or pure sine wave, and the sine wave is superimposed on many other wave-forming voltages, and these voltages are added to the load to form a current. The formation of these voltages is more complex, there are power supply system internal generation: such as electromagnetic relay work or EDM production of spike pulses, there are also external electromagnetic interference pulses, such as automobile ignition pulses, lightning induction pulses, although these pulse currents are small, but the voltage is high, the destructive force of the diode and even the electronic components behind is not small, after the parallel diode, because the voltage at both ends of the capacitor can not be abruptly changed, so these voltages are neutralized after the capacitor is added to the capacitor through the filter capacitor of the power supply.

Weaken the damage of these impulse voltages to the electronic components in the diode and power supply circuits, and even protect other functional circuits. It also makes the regulated DC voltage more pure, eliminating undesirable interference signals, such as audio signals and eliminating noise. Of course, when the spike pulse voltage reaches a certain level, it will damage the capacitor and diode.

Absorbs instantaneous overvoltages to prevent breakdown diodes.

Spike absorption to prevent breakdown of the diode.