Meet transistor #Q615. It's labeled as C114 TSC but when I googled it I came up as a possible diode. On Digikey it looked more like a BJT transistor. This is from a Sony Stereo. This board controls the 3 CD player. This stereo has been scrapped and I just wanted to play with the bi-color LED's. If they can suit a purpose I may incorporate them into my truck. Details on that are unimportant. What I'm trying to do is figure this board out. Below is a schematic I made from following the single layer traces. It's pretty straight forward but could use a little help identifying two things about this board: 1) what voltage are they sending to the LED's? And 2) What type of control device is Q613, Q614 & Q615? (Q615 in picture)

 

japaneese transistors usually skip prefix 2s... did you try 2sc114

 

I think it could be a BC114. I have bought BC557 transistors (From Farnell.) and they were marked C557.

Les.

 

From the diagram I expect that a C114 is an NPN transistor. What voltage they are using depends on what current is being used for the LEDs.

 

Its a 2SC114 transistor Vcbo 50V, Ic 200 ma,Pc 750 mw. Had to look it up in a very old Japanese transistor manual as google wasn't very helpful. Going by the resistor values for the LEDs around 5 to 6V DC.

 

Wasn't sure if they were BJT's or some sort of FET.

No, I only tried C114. I'll try the 2SC114 and some variances of it.

As for voltage, I'm going to guess that they want to use 10 mA as a starting point. These lights were not intended to be bright, just to indicate which CD was being played, CD1, CD2 or CD3. Since they are bi-color I'm assuming there was some meaning to different colors, hence pins 4 and 5 appear to set up which color would be used and the transistors would determine which light was on at which instant. AND I don't even know what colors they are yet.

Pins 1, 2 & 3 appear to be connected to a "Gate" on each Q. Since it's on the side of the device I thought it might be a FET or MOSFET, but if it's an NPN then shouldn't the base be the center pin of Q615?

Searching through using expanded numbers I found http://www.onsemi.com/pub/Collateral/DTC114Y-D.PDF, which appears to have built in internal resistance. Closest thing so far, but still bewaffling me.

 

Its a 2SC114 transistor

Sanyo Stereo. Old enough to be obsolete. In fact, every component on the board is PTH, other than the micro controller.

 

Ic 200Ma

M = 1000000, Ic = 200 x 1000000A?
Ic = 200 mA.

 

Holding pin 6 low and driving pins 3, 4 & 5 high (5 volts) Both D631 LED elements illuminate. Pin 4 drives the yellow element, pin 5 drives the green element. It would stand to reason that pin 2 high would light D632 and pin 1 lights D633.

 

M = 1000000, Ic = 200 x 1000000A?
Ic = 200 mA.

Use context clues, obviously a shift key usage error.
http://www.dictionary.com/e/context-clues/

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