TLV62080: capacitive load and device features

Hello Davide,

Thank you for using E2E,

Davide Tosatto said:

I want to implement a TLV62080DSGR in my design and I would like to clarify some doubts.

TLV62080 is a old device, I would instead recommend TPS62A02 data sheet, product information and support | TI.com which is our low cost hero device.

Davide Tosatto said:

In his datasheet, it is written that "the device is designed to operate with an output capacitance of 10 to 100 uF and beyond" and then "load transient testing and measuring the bode plot are good ways to verify stability with larger capacitor values". Based on your experience would it be a problem using a 700uF ceramic capacitive load?

TI has evaluated the following LC combination. If you would like to operated beyond the recommended LC combination, it's better to check the stability of the device. I don't have any data related to 700uF output capacitor.

Davide Tosatto said:

Moreover, there are no quotes about features like "output over-voltage protection" and "negative over-current protection". Are not they present? Could the device be susceptible to these events?

This device only has the over current protection as mentioned in the section 8.3.8 in datasheet.

If you would like to protect the device from the negative current from the output side then, you can use a Schottky diode at the output side.

Thank you & regards,

Moheddin.

Hello Moheddin,

Moheddin Pasha Shaik said:

TLV62080 is a old device, I would instead recommend TPS62A02 data sheet, product information and support | TI.com which is our low cost hero device.

thank you for your recommendation but it does not fit my application because I need one with at least 6V max recommended operating voltage. I am looking for alternative components in TI Buck converter product catalogue, so I would be glad to receive other suggestions.

Moheddin Pasha Shaik said:

TI has evaluated the following LC combination. If you would like to operated beyond the recommended LC combination, it's better to check the stability of the device. I don't have any data related to 700uF output capacitor.

For other TI components, I have used the WEBENCH designer to evaluate the device stability, so if there are no other ways I will have to check the stability in the laboratory.

Moheddin Pasha Shaik said:

If you would like to protect the device from the negative current from the output side then, you can use a Schottky diode at the output side.

And it is needed to ensure the output max voltage is below Vin+0.3V, isn't it?

Thank you,

Davide

Hello Moheddin,

I am still here asking a new related question .

Even if the TLV62080 does not have a negative current protection, how much negative current could it sustain?

Thank you,

Davide

Hello Davide,

Davide Tosatto said:

Even if the TLV62080 does not have a negative current protection, how much negative current could it sustain?

This a DCS control device and the only way to have negative current is by increasing the Vout than Vin. In this case it would violate out SW pin Abs max ratings.

In case if your application really needs negative current, then go with  TPS628512 data sheet, product information and support | TI.com

which has a Low-side FET negative current limit DC value –1.8 A.

Thank you & regards,

Moheddin.

Hello Moheddin,

Moheddin Pasha Shaik said:

In case if your application really needs negative current, then go with  TPS628512 data sheet, product information and support | TI.com

which has a Low-side FET negative current limit DC value –1.8 A.

I could evaluate this component. His datasheet says it has a 200uF max effective output capacitance, it has already been tested that higher output capacitance could lead to instability or do I have to check myself? Instability depends only on output capacitance value or other parameters (like input voltage, output voltage, input capacitor...) ?

Thank you,

Davide

Hello Davide,

What is the maximum capacitance for your application? 

Davide Tosatto said:

I could evaluate this component. His datasheet says it has a 200uF max effective output capacitance, it has already been tested that higher output capacitance could lead to instability or do I have to check myself? Instability depends only on output capacitance value or other parameters (like input voltage, output voltage, input capacitor...) ?

The stability of the device mainly depends upon the Inductor and output capacitor, you can check the stability of the device if the L & COUT are beyond our datasheet requirements.

I would also recommend to look into this device parallelly -TPS628302 data sheet, product information and support | TI.com

Thank you & regards,

Moheddin.