LMR14030-Q1: LMR14030-Q1 Low Dropout Curve

tateo yamashiro

Guru 10890 points

Part Number: LMR14030-Q1
Other Parts Discussed in Thread: LMR14030, TPS54340

Hi,

We got a question from customer about LMR14030-Q1.
Could you help us?

[Question]
Is there the dropout curve at their condition or similar condition?

Vout=5V
Iout=2.5A
fsw=2.2MHz
Ta=70C

We are thinking the dropout curve depends on the operating temperature. How much is the variation of the dropout curve from Figure 9 at Ta=70C?

Best Regards,
tateo

over 7 years ago

0 Andy Chen over 7 years ago

TI__Mastermind 34555 points

Hi,

Data sheet curve tested at Ta=25C, for rough estimation, the RDS(on) will increase about 40mohm if Ta=70C. so additional voltage drop is 2.5A*40mohm=1000mV, sothe drop-out curve will move 1V down.

0 tateo yamashiro over 7 years ago in reply to Andy Chen

Guru 10890 points

Hi, Thank you for your reply. The Rds(on) will increase about 40mohm. So additional drop is 2.5A*40mohm=100mV, isn't it?

Best Regards,
tateo

0 tateo yamashiro over 7 years ago in reply to Andy Chen

Guru 10890 points

Hi, Sorry to bother you again. Could you provide the characteristics of Rds_on vs Junction temperature? They want to estimate Rds_on at Tj=130C.

Best Regards,
tateo

0 Andy Chen over 7 years ago in reply to tateo yamashiro

TI__Mastermind 34555 points

Hi,

Sorry that LMR14030 has no Rds(on) Vs Tj curve, you can refer to TPS54340 data sheet Figyre 1. as they have similar RDS(on) and same package.

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LMR14030-Q1: LMR14030-Q1 Low Dropout Curve