Lt1074

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

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.

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

Blueteeth said:

Google is your friend

Click to expand...

unless you live in china!

What is the unregulated input voltage?

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

3lectrokid said:

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

Click to expand...

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?