You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
34 lines
1.3 KiB
34 lines
1.3 KiB
|
|
limits: |
|
output voltage: 2V (minimum of lm723) - 28V (max of lm358) |
|
output current: 3A parallel, 1.5A series (max of transformer) |
|
|
|
|
|
new features: |
|
- working current limit :P |
|
- calculate actual filtering cap value for some value of ripple at 3A |
|
- I=CdV/dt, C=Idt/dV, dt=8.33ms (one half of 1/60 because full wave), |
|
for 3Vpp ripple at 3A, 3*0.00833/3 = 8,330uF, (2x 50V 4700uF in parallel) |
|
for 1Vpp ripple at 3A, 3*0.00833/1 = 24,990uF :o |
|
- calculate worst case power dissapation value for pass transistor |
|
- at 100C case temp, 3055 can safely dissipate about 60W |
|
15V-2V = 13V*3A = 39W (with relay switching xformer leads at 15V) |
|
should probably still add better heatsink with fan |
|
- use keyed cable connectors |
|
- high side current meausurement resistor |
|
- need to use differential amplifier with good CMRR |
|
- SCR overvoltage protection |
|
|
|
- relays: |
|
- on/off switch disables outputs |
|
- switchable output |
|
- voltage range switches transformer configuration |
|
- 2-15V parallel output, 3A |
|
- 15-28V series output, 1.5A |
|
- may need to also switch off output when changing the voltage to |
|
prevent inductive spikes from switching the xformer going to |
|
the output |
|
|
|
- kicad: |
|
- virtual symbols for off-board components (ac side protection/switch) |
|
^ https://forum.kicad.info/t/off-board-components-in-kicad-5/22286
|
|
|