Hello everyone
Anyone familiar or have triedterntive transistor for this one?
It's high voltage fast switching transistor installed at UPS,
Any help for equivelant number?
Datasheets attached

 

Hello,

Mouser seems to sell them:
https://eu.mouser.com/c/semiconductors/discrete-semiconductors/transistors/?series=KSP44

Bertus

 

MJE 13001 or 2 or 3 are commonly used for fast switching purpose.

 

Hello,

You could have a look in the transistor selector guide:
https://archive.org/details/Towers-TowersInternationalTransistorSelector

Bertus

 

MJE 13001/13002 can work, but it's pinout is different

 

PMBTA44,215
CMPTA46 TR PBFREE
2SC4002E-AA
PBHV8540X-QX
PMBTA44-QR
FMMT458W

 

MJE 13001/13002 can work, but it's pinout is different

The switching speed same?, or faster?

 

PMBTA44,215
CMPTA46 TR PBFREE
2SC4002E-AA
PBHV8540X-QX
PMBTA44-QR
FMMT458W

How did you find replacements please?

 

How did you find replacements please?

digikey
Go to the link and you will see what I found.
Let me teach you how to do this. Go to digikey.com (or almost a company that sales transistors) mouser.com etc.
In the search window type in transistor. In the digikey example next they want to know what type and pick bipolar. Next pick single transistor not array.
pick NPN not PNP
There are windows with data in them. For example I selected Collector current from 100mA to 500mA. (apply all)
Pick Collector voltage 400 to 600V (apply all)
Power 250mW to 600mW. apply
Pick transistors with Frequency above 10Mhz. apply
There is an optional check box for "in stock" which I did not do because I am looking for numbers not ordering right now.
By now you should have the data I got in the link above.

Each transistor should have a picture and a datasheet.
I was not looking for an exact replacement because there is not really one. I design circuits. I need a High Voltage, Fast, low current, low power, NPN transistor.

There is a story about fishing and feeding a man. Hope you learned how to fish for parts.

 

The switching speed same?, or faster?

Switching speed is comparable, so MJE 13001, 13002 is a suitable substitute

 

KSA44 is the same as an MPSA44. The KSA prefix used to be Samsung, and their transistor range was bought by Fairchild.