TLV733P-Q1: higher PSRR solution

Patrick Chen(TPE System & Application)

Expert 3430 points

Part Number: TLV733P-Q1
Other Parts Discussed in Thread: LP5907-Q1, TLV702-Q1, , LP5912-Q1, LP5912

Hi Sir,

My customer is using TLV73333PQDRVRQ1/TLV73318PQDRVRQ1 on their system, and facing a PSRR issue.

So they are looking for a higher PSRR solution with same package and pin out.

The requirement as below:

LDO 5V to 3.3V, LDO 5V to 1.8V.

Iout: >300mA

High PSRR, (> 65dB(min)@1KHz~3KHz ; >55 dB(min)@3KHz~30KHz)

Many thanks,

Patrick

over 6 years ago

0 Ryan Eslinger over 6 years ago

TI__Guru 55940 points

Hi Patrick,

Could you clarify what your nominal output current is? We need to make sure that the LDO is rated for your nominal output current.

Since TLV733P-Q1 is a 300 mA LDO, for now we will assume that you meant that Iout is less than 300 mA. In this case, please consider TLV702-Q1. If your nominal load is 250 mA or less, please consider LP5907-Q1.

Very Respectfully,
Ryan

0 Patrick Chen(TPE System & Application) over 6 years ago in reply to Ryan Eslinger

TI__Expert 3430 points

Hi Ryan,

The TLV702-Q1 WSON package(1.5mmx1.5mm) is not same package as TLV733P-Q1 WSON package(2mmx2mm).

Do you have other suggestion?

Thanks,

Patrick

0 Ryan Eslinger over 6 years ago in reply to Patrick Chen(TPE System & Application)

TI__Guru 55940 points

Hi Patrick,

Additionally please consider LP5912-Q1.

Very Respectfully,
Ryan

0 Patrick Chen(TPE System & Application) over 6 years ago in reply to Ryan Eslinger

TI__Expert 3430 points

Hi Ryan,

Many thanks for help. but the Pin5 is different.

TLV733 is NC on pin5 and LP5912 is GND.

Do you think we have to connect LP5912 pin5 to GND or it will work fine with pin5 floating?

Many thanks,

Patrick

0 Ryan Eslinger over 6 years ago in reply to Patrick Chen(TPE System & Application)

TI__Guru 55940 points

Hi Patrick,

The GND pin of a linear regulator is the reference for all internal voltages. If floating, Vout will vary between GND and Input.

Very Respectfully,
Ryan

0 Patrick Chen(TPE System & Application) over 6 years ago in reply to Ryan Eslinger

TI__Expert 3430 points

Hi Ryan,

Thanks for help.

Patrick

Power management

Power management forum

TLV733P-Q1: higher PSRR solution