Техническая Спецификация для STMicroelectronics Evaluation board for A5970AD EVALA5970AD EVALA5970AD

DocID14661 Rev 5

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The A5970AD device features two types of current limit protection: pulse-by-pulse and 
frequency foldback.

The schematic of the current limitation circuitry for the pulse-by-pulse protection is shown in 

. The output power PDMOS transistor is split into two parallel PDMOS transistors. 

The smallest one includes a resistor in series, R

SENSE

. The current is sensed through 

R

SENSE

 and if it reaches the threshold, the mirror becomes unbalanced and the PDMOS is 

switched off until the next falling edge of the internal clock pulse. Due to this reduction of the 

A5970AD

A5970AD

A5970AD

A5970AD