LM2621: LM2621MM, not getting 10v output

ASHISH CHHONKAR

Part Number: LM2621
Other Parts Discussed in Thread: TPS61088

I want to convert the 3.7v- 5v input to 10 v output. I prepare a circuit but did not get 10v . Output voltage is 4.88v instead of 10v.

over 5 years ago

0 Zack Liu over 5 years ago

TI__Mastermind 34201 points

Hi Ashish,

1. VDD pin has a 5V maximum voltage limit. So you cannot connect the vo to VDD directly. You could use a 4.9V zener diode to generate a voltage for VDD,EN and BOOT.

2. What's the load current? Are you just simulating in PC or doing a test on bench? If it is a test result, please provide the key waveforms, such as SW, inductor current, Vin.

0 ASHISH CHHONKAR over 5 years ago in reply to Zack Liu

Prodigy 30 points

Thanks for your reply

Our requirement is to generate 10v (700mA) from input source 1 cell lithium battery. We tested our schematic on PCB an voltage stable at 4.88v. We requires 1.8v logic signal for enable chip from microprocessor side.

I request you to please suggest the right schematic for our specification.

0 Zack Liu over 5 years ago in reply to ASHISH CHHONKAR

TI__Mastermind 34201 points

Hi Ashish,

You can use TPS61088. It is a fully integrated synchronous boost converter with Enable function.

0 ASHISH CHHONKAR over 5 years ago in reply to Zack Liu

Prodigy 30 points

Sir,
Can you provide final schematic for 10v?

0 Zack Liu over 5 years ago in reply to ASHISH CHHONKAR

TI__Mastermind 34201 points

Hi Ashish,

Please refer to the below schematic. 10V@700mA is generated by TPS61088.

You can use TI webench tool to run simulation.

Power management

Power management forum

LM2621: LM2621MM, not getting 10v output