DRV103: DRV103H: Unregulated supply

Hello Stephan,

Please understand that we have not characterized the DRV103 under the unusual Pdc conditions that you are inquiring about so the answers I am providing are based on my best understanding of the device.

1. Without any capacity the maximum voltage is 36 V and minimum is 26 V. Can the DRV103 handle this ripple (300/360 Hz)? 

   The absolute maximum Supply Voltage rating is +40 V. Therefore, it should be able to tolerate the +36 V peak level. The maximum operating voltage is +32 V and I do expect the device is still operational when the voltage exceeds that level, but TI cannot make any assurances about operation above +32 V. 

   The DRV103 datasheet states, “The DRV103 operates from a single +8V to +32V supply with excellent performance. Most behavior remains unchanged throughout the full operating voltage range. Parameters that vary significantly with operating voltage are shown in the Typical Performance Curves.” Curves indicating performance related to the +40 V Absolute Maximum are QUIESCENT CURRENT vs JUNCTION TEMPERATURE, and DELAY vs JUNCTION TEMPERATURE. 

2. The DRV103 maximum operating voltage is 32 V, will the rectified peaks damage the part (in the long term) or affect it in any other way?

    The DRV103 processing supports the +40 V Absolute Maximum, and +36 V level does not exceed that level. The higher voltage itself should not be issue that affects the short or long-term reliability of the device. Operating with a higher voltage supply does increase the power dissipation and raises the junction temperatures. Heat is a factor that affects the long-term life of a semiconductor’s lifetime and can be predicted by the Arrhenius' equation. Likely, if the output DMOS transistor is sinking significant current from a load its power dissipation will be the largest contributor to self-heating.

Regards, Thomas

Precision Amplifiers Applications Engineering