TPS767D301

Hi Alexander,

The back-gate diode is the body diode inherent to the structure of a MOSFET. We currently do not the information available on the forward voltage of this diode, or the I-V curve for it, and the data will take some time to collect.

So I can better assist you, what would you like to use the body diode for?

Regards,

David

Hi David,

we use the linear regulator to supply the infinion microcontroller XC167. The input voltage of the regulator is 5 V and the output 1 voltage is 3.3 V. The 5 V and 3.3 V are supply voltages of the microcontroller. The requirement for power sequencing of the microcontroller is (5 V supply - 3.3 V supply) > -0.5V. If the forward voltage of the body diode is below 0.5 V, for power down no additional diode is necessary .

Best regards,

Alexander

Hi Alexander,

Thank you for the information - you may want to also consider the TPS73801 which grounds the body of the pass device removing the effect of the body diode. 

Regards,

David

Alexander,

Just realized I forgot to mention this - I will also be measuring the forward voltage on a few of the TPS767D301 once they arrive here at the office.

Regards,

David

Alexander,

I did a bench check on 10 units, both channels, and found the forward voltage to be around 542.5mV +/- 5mV.

Regards,

David

Hi David,

can you please provide the current and the temperature for the forward voltage measurement.

 

Best regards,

 

Alexander

Alexander,

The test current was 1mA and the test was done at 25C.

Regards,

David

TPS767D301 increat temparature high!

Dear All,

We designed a power schematic for DSP as TPS767D301. Voltage output at Vout1 = 1.89 V, Vout2 = 3.3V. But after about 15s, IC TPS767D301 increate temparature than 70 C. I have up image of schematic and PCB folow url :
www.upsieutoc.com/.../DJR3 (PCB)
www.upsieutoc.com/.../DJRA (Schematic)
Can you help me reson increate temparature of TPS767D301? I don't see my design other with datasheet of TPS767D301. Thanks many!

Hi Thanh,

The links that you posted on the forum do not work. Using the button that I circled in blue you will be able to upload the schematics to the site. Also, it would be useful if you can provide the input voltage and current from each output. This will help determine what is causing the increase in temperature of the device.

Best Regards,

Mark

Dear Mark Sellers,

  Thank you for your reply, I insert again my schematic and PCB. Can you help me?

Dear Mark Sellers,

  Thank you for your reply, I insert again my schematic and PCB. Can you help me?

I check again datasheet of TPS767D301, but i don't see problem in my schematic. Haizz, may be by quality of IC. :(

Hi Achut,
Ater looking at your layout and schematic I did notice that you did not connect the thermal pad on the bottom of the device. This will be important to dissipate heat by using the PCB as a heat sink for the LDO. The thermal specs that are listed in the datasheet are only valid for having the thermal pad connected as specified in the datasheet. One more thing to consider is you have 5V as the supply voltage to the device, depending on the current that the LDO is providing it is not unreasonable to see this kind of heating especially without the thernal pad connected. One way to reduce the amount of power that is being dissipated across the device is to reduce the headroom that you have by lowering the input voltage. If the input voltages are adjusted be sure to ensure that all of the requirements in the Electrical Characteristics table on page 3 are met for proper device functionality.
Best Regards,Mark