simpe constant U/I supply. Would they work?

Status
Not open for further replies.
L

Lauris

Newbie level 6
Joined
Apr 24, 2012
Messages
11
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Location
Lithuania, Vlinius
Activity points
1,355
Hello everyone,

can anyone coment about how these schematics would act? And would they do that in order I think they should


Also maybe anyone have any other offers on making simple constant U/I schematics which are prooved working. Requaerments are same: constant u - 10-80V range to 5V up to 100mA. And constant I 10-20V range, 1,1A output.

Tahnk you in advance,
Laurynas.
 

1st schematic should be emitter follower out, non inverting with negative feedback, and pull down resistor. but Q1 may overheat if Vin = 80V @ 100mA

2nd schematic may be overkill and also has positive feedback (NG) I suggest you use LM317 with transistor to use ADJ-OUT 1.250V internal reg drop for constant current control. See chip App notes. It is better with TO3 case for more heatsinking but has thermal shutfown. EACH device is rated for 40V so cascade two LM317 for 80V operation with suitable zener or TVS for sharing the drop. **broken link removed**
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…