UCC21756-Q1: How to modify UCC21750 EVM to fit UCC21756

Raymond Tan

Part Number: UCC21756-Q1
Other Parts Discussed in Thread: UCC21732

Hi,

I refer to your document, module and gate driver compatibility

https://www.ti.com/lit/ug/sluuck0/sluuck0.pdf?ts=1707984265782&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FUCC21750

Section 2.2, it wrote that i need to modify the threshold of the EVM.

How do i do that?
Section 6.3 didn’t state for UCC 21756

7 months ago

0 Sasikala Thangam 7 months ago

TI__Expert 6610 points

Hi Raymond,

Thanks for your interest in using the UCC21756 isolated gate driver. The required Vdesat threshold at the gate driver is 5V. Please refer section 3.4.6.1 which talks about how to calculate the desat threshold,

VDET = VDESAT − VZ − n × VF − Ichg × Rlim

In the formula for UCC21756, VDESAT = 5V, Vz = 2.7V, n=2, VF=~0.7V, I chg = 500uA and Rlim is 475 ohms. it helps to define the actual detection voltage at the module.

Hope it helps.

Thanks

Sasi

0 Raymond Tan 7 months ago in reply to Sasikala Thangam

Prodigy 170 points

Hi, I am looking at the TI recommended EVM board, UCC21750QDWEVM-025

when I logged into the UCC21756 website https://www.ti.com/product/UCC21756-Q1

Inside the document, the user manual wrote about UCC21732.

Is there a version on the schematic and BOM list for 21750?

want to check, if i want to test the UCC21756,

i need to get this EVM board, UCC21750QDWEVM-025,

1. change the chip to UCC21756

2. Rlim value increase to 1K ohm to make it respond faster

0 Sasikala Thangam 7 months ago in reply to Raymond Tan

TI__Expert 6610 points

Hi Raymond,

UCC217xxEVM Design Files (zip) - this link has the design files for 0x750 variation and also BOM info. Hope it helps.

Thanks

Sasi

Power management

Power management forum

UCC21756-Q1: How to modify UCC21750 EVM to fit UCC21756