LM723: What connection is used for Vz?

Harshith Alvakonda

Part Number: LM723

Hello Sir/Madam,

I am graduate student from University of Colorado,Boulder.I am using LM723 for my student project and I was not sure where exactly should Vz (pin 9 as per connection diagram from the datasheet -Figure 1) be connected in Figure 4.

Also, I have an LED as my load which has rating of 5volts, 20mA. Would this be fine to work with in this application?

If I plan to have variable resistor varying the output voltage from 2v-7v would this work as well?

Hoping for your feedback!

Thank you and appreciate your help in advance!

Kind Regards,

Harshith Alvakonda.

over 7 years ago

0 Kirby Kruckmeyer96848 over 7 years ago

TI__Genius 17125 points

Hello Harshith,

The Vz pin is used to drive an external transistor for applications needing more than 150 mA. If not needed, it can be left floating.

The LM723 is an older part. It does allow for greater flexibility but newer parts are simpler to design in. Have you tried WeBench to help you with your application?

www.ti.com/.../power-designer.html

0 Harshith Alvakonda over 7 years ago in reply to Kirby Kruckmeyer96848

Prodigy 20 points

Thank you for the notes. Could I know if it is possible to provide LM723 model on TINA Simulator? as this would be greatly helpful for simulating and looking at the results.

0 Ramesh Khanna over 7 years ago in reply to Harshith Alvakonda

TI__Expert 7445 points

Hi Harshith,

We do not have TINA simulation model for LM723 that is available at the moment.

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LM723: What connection is used for Vz?