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Talk:Diode-connected transistor

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This article had previously linked to "constant-current diode". I believe this is incorrect, and added a short description of my understanding of the construction of diode-connected transistors. ---- Miles

The Base-Collector junction can also be used as a diode to overcome the reverse-Vbe limitations of the Base-Emitter junction. The trade-off is higher reverse current leakage and junction capacitance. Source: https://electronics.stackexchange.com/questions/50633/usage-of-a-transistor-configured-as-diode

"It is a common practice in precision analog electronics to use Bipolar transistors as diodes. The purpose is to obtain a very low leakage diode. For example, a 3904 type transistor will have <1pA of reverse leakage using the Base Emitter junction. However, it turns into a zener diode at around 6.8V. Works great for 5V and lower voltage logic circuits. Higher current and reverse voltage is achieved by using the Base as anode and the collector as the cathode. Still an excellent low leakage diode at around 10pA and now you get the voltage rating of the transistor and improved current. This will not be a high speed diode. Higher speed is achieved by shorting Collector to Base (Anode) and using the emitter as Cathode. However, reverse voltage must be limited to <5V." 107.130.194.130 (talk) 13:53, 12 September 2023 (UTC)[reply]