Choice Stack configuration and feedback on TOPSwitch
I need design power supplly for soldering station.
Input voltage - AC 230 (for use in EU)
Output Power: min. 2W max. 160W
Output voltage
- Output 1 : 5,7V, current 200mA - 800mA high requirement for accuracy , say +- 1%
- Output 2: 24 up to 25V, current 0 max 4A accuracy +- 10% (for switched heating element and alternative for driving)
- Output 3: 48 up to 50V, current 0 max 3A accuracy +- 10% (for switched heating element)
I would like to use TOP271EG, but do not know how to choose the configuration of the stack and and how output connect feedback? Output power is minimum (all heating element off) 2W max power is 160W, load {heating element) is switched.
Comments
Thanks for the answer.
I ask otherwise.
Example:
Power supply with TOP271E
Input -110-265V
Output 1: 5,7V, 0,2A - 1A
Output 2: 24V, 0,01A - 3.3A
Output 3: 48V, 0,01A - 3.0A
Max output power 150W
Feedback from output 1 5,7.
Example mode load source:
Output 1: consumption fluctuates between 20mA - 600mA
Output 2: 1mA 9 switching 3,3A switched frequenci is max 1kHz , 1ms On / 1ms Off, .
Output 3: up tp 1mA
How it will respond to the source switching to 80W output 2
My point is, within what limits will vary the output voltage of 5.7 V to output 1?
It is clear that it depends on the concrete realization of the output phase source, but for approximately Say Each output has 2x 680uF C and small 3.3 uH inductor
If you take most of your feedback from output 2, then your should have a very good response.
It may be needed to tune the loop a little bit,
You can take the attached file as a reference. This is a PI expert file. You can download the program from:
http://www.powerint.com/en/design-support/pi-expert-design-software
For the low voltage output, you need to add a liner regulator.
Flyback converters are a good choice for multiple output voltages because you need to add few components tfor each aditional output you are adding. However, when required accuracy in the output, it is tricky because the desired accuracy depends on how the load will change. Let say, in one output you have maximum load while in another output you have no load. Under this condition, the unloaded voltage will tend to go high.
What I mean you need to play with the circuit to tune it for proper output tolerances.
Your feedback resistor R16, determines the accurate output voltage on the output it is sensing. However, you can split the feedback. Instead of having a single feedback branch (R16) sensing one output. You can have two resistors sensing two outputs. Just make the right calculation and split the total amount of current in tow branches.
I can not give you better help for you. You need to start putting together a prototype and tune it for your cross regulation
Good luck