LM2623: /LM51501-Q1 - Boost 1.8-3.1 V to 6V 400mA

Tom Robson

Part Number: LM2623
Other Parts Discussed in Thread: LM51501-Q1, , TPS61023, LMR61428

Hello,

I have a very similar query to an old post which is linked here.

My requirements are for a boost converter that provides up to 400mA at 6V. The minimum input voltage should be 1.8V and the max input 3.1V. I'll be using a CR2 Lithium Battery.

The WeBench suggests the LM51501-Q1 however I'm not sure that this is ideal for use in a non-automotive application? My solution should prioritise low Iq and small physical size.

The linked post for LM2623 suggests it could be suitable but I understand it's quite an old chip. Are there any other TI chips that are more suitable for my requirements?

Thanks,

Tom

over 2 years ago

0 EM over 2 years ago

TI__Genius 11215 points

Hello,

Thanks for reaching out. The expert for this family of devices is currently out of office and will reply as soon as possible. Thank you for your patience.

Kind regards,
EM

0 Tom Robson over 2 years ago in reply to EM

Prodigy 10 points

Thank you

0 Zack Liu over 2 years ago in reply to Tom Robson

TI__Mastermind 34201 points

Hi Tom,

TI has lots of boost converter that Vout is up to 5.5V. if you can change your application Vout to 5.5V, the recommended boost converter is TPS61023.

If you insists to have 6V Vout, LMR61428 is recommended.

0 Tom Robson over 2 years ago in reply to Zack Liu

Prodigy 10 points

Thank you. I will look into these options

0 Tom Robson over 2 years ago in reply to Zack Liu

Prodigy 10 points

On looking further, the LMR61428 does not look like it meets by requirements in Webench, due to the duty cycle exceeding the limit. Any other suggestions?

0 Eric Yue over 2 years ago in reply to Tom Robson

TI__Expert 5180 points

Hi Tom,

LMR61428 can be used in this application, because its control scheme uses a hysteresis window to regulate the output voltage. When the output voltage is below the upper threshold of the window, the LMR61428 switches continuously with a fixed duty cycle of about 70%. When the output voltage hits the upper threshold of the window, the LMR61428 stops switching completely.

Duty cycle has little effect on output voltage because LMR61428 is not a typical PWM control scheme converter, Webench may not be very accurate for this control.

Best Regards,

Eric Yue

0 Tom Robson over 2 years ago in reply to Eric Yue

Prodigy 10 points

Thank you for the explanation!

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LM2623: /LM51501-Q1 - Boost 1.8-3.1 V to 6V 400mA