TLV61220 accuracy

Antony Pierre Carvajales

Intellectual 1910 points

Other Parts Discussed in Thread: TLV61220, LM2735

Hi Team

I looked for the accuracy of the TLV61220 in the documents below and could not find it

Low Input Voltage Step-Up Converter in Thin SOT-23 Package

Basic Calculation of a Boost Converter's Power Stage (Rev. C)

TLV61220EVM-120, Low-Input Voltage, Step-Up Converter Evaluation Module

Plase provide me or show me were to find the accuracy of the TLV61220 operating on the following conditions

Vout (V)	4.5V
Vin (V)	3.1 to 3.5V
Iout (mA)	10 to 50 mA
Temperature of operation (°C)	10° to 70°

Thanks!!

Antony C.

over 10 years ago

0 JohnTucker over 10 years ago

TI__Guru**** 191445 points

The basic specification you are looking for is the Vfb voltage, 483 mV min, 500 mV typ, 523 mV max.

Additionally the line and load regulation is specified as typically 0.5% fro each. The resolution of the regulation graphs in the datasheet (figs 10 and 11) are not at a vertical resolution where you can see that percentage change. They look essentially flat.

0 Antony Pierre Carvajales over 10 years ago in reply to JohnTucker

TI__Intellectual 1910 points

Thank you John for your prompt response

The customer is looking for a synchronous boost with an accuracy of 3% or better.

If I understand correctly you are saying that to calculate the accuracy I need to add the feedback voltage range which is ~2.53% + 0.5% line regulation + 0.5% load regulation = gives an output voltage accuracy of 3.5%. If I am not mistaking this estimate does not take into account temperature ranges and tolerance of the resistor divider.

If this is correct, this device will not fit the requirements of 3% output voltage accuracy.

Please comment and advice

Thank you John

Regards,

Antony C.

0 JohnTucker over 10 years ago in reply to Antony Pierre Carvajales

TI__Guru**** 191445 points

That is generally how it works. I think the VFB tolerance is actually over temperature. I am somewhat surprised about the typical line and load regulation numbers. Usually our parts perform a little better than that, but I don't directly support the TLV61220. You might be best off to search for a part with 1% reference accuracy. My group mostly does buck converters.

0 JohnTucker over 10 years ago in reply to JohnTucker

TI__Guru**** 191445 points

LM2735 has 2% reference tolerance over your temp range.

0 Antony Pierre Carvajales over 10 years ago in reply to JohnTucker

TI__Intellectual 1910 points

Thank you John much appreciated

Power management

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TLV61220 accuracy