Lt1074

[3lectrokid]

Hey,
I just broght a LT1074 switching voltage regulator from rapid but i do not understand how to change the output voltage. i do not understand much on switching regulators but have read through wikipedia here. I would like an output of 24 volts for an audio system. the product is **broken link removed** and the product datasheet is **broken link removed**.

Thank you all for your time reading this post

 

[Roff]

What is your input voltage?
Also, I ran a simulation, and the output ripple was about 0.5Vp-p at about 3kHz. Can you tolerate this?
BTW, the part you linked to at Rapid is an LT1076, which is only good for 2A.

 

[Blueteeth]

Go over the datasheet again and look for the example circuit. Almost all 'adjustable' switching regulators have a 'FB' (feedback) pin, which is used to set the output voltage via a voltage divider. I tihnk the datasheet even gives you the formula for working out the resistor values for a given output voltage. The chip will try to keep the votlage at the feedback pin at 2.21V (according to the datasheet), so, you need to make a resistor deivider which can produce 2.21V, from 24V (your output). Google is your friend

 

[ghostman11]

Google is your friend

unless you live in china!

 

[MikeMl]

What is the unregulated input voltage?

 

[3lectrokid]

the input voltage will be 30v - the voltage drop of the rectifier im guessing around 1.4 volts

 

[MikeMl]

the input voltage will be 30v - the voltage drop of the rectifier im guessing around 1.4 volts

Are you saying that you are using a 30V AC transformer?

Full-wave Rectifier?

50 or 60Hz?

How large a filter capacitor between the rectifier and the input to the LT1074?