Optocoupler
TLP521-1 LP521-4 PC817 EL357
Darlington tube
Darlington is two transistors connected together, and the polarity is only recognized by the front transistor.
MJD127
TIP series, TIP41C TIP41c can be replaced by D880, D633, C2073, 2N3733, C2335
TIP122 TIP120-TIP127 ULN2803 ULN2003 ULN2804
mos tube
IRF640 IRF840
Triode
NPN-S8050 PNP-S8550
diode
IN4007 IN4148 IN5824 (freewheeling)
http://www.elecfans.com/yuanqijian/erjiguang/20180304642590.html
1N4007 is an ordinary rectifier diode, with a withstand voltage of 1000V, a current of 1A, and a reverse recovery time of ms. It can only be used in low frequency circuits.
1N4148 is a switching diode, with a voltage resistance of 100V, a current of 150mA, and a fast reverse recovery speed.
SS34 SS14
The characteristic of ss14 Schottky tube bai is fast working speed du, high current, but low reverse withstand voltage (zhiSS14 only 40V), so it cannot be directly replaced with ordinary rectifier tubes (such as 1N4007). The latter is characterized by large current and slow speed, but high reverse withstand voltage (1N4007, withstand voltage 1000V) if it is forcibly applied, it may cause SS14 to be broken down. The role of S14: a device with unidirectional conductivity. But its most notable feature is the extremely short reverse recovery time, so it is mostly used as high-frequency, low-voltage, high-current rectifier diodes, freewheeling diodes, and protection diodes.
Schottky diodes are metal-semiconductor devices made of precious metals (gold, silver, aluminum, platinum, etc.) A as the anode and N-type semiconductor B as the cathode. The barrier formed on the contact surface of the two has rectification characteristics.
SS34 is a SMD Schottky diode, commonly used in small current (model) ESCs for instant rectification of circuits. The white segment is the negative electrode.
Voltage regulator chip LDO
7805 series LM2596 BM2596 series AMS1117 series