DRV8837: Short-circuit protection

Part Number:DRV8837

Hi,Team

I need some help on the current limit for the DRV8837. Here is the problem description.

My application for DRV8837 is shown as below.R1 is not used. VCC=4V，IN1 and nSLEEP is pull high by VCC, A PWM signal (4V,50%Duty)  is provided to IN2.

 OUT1 is short to OUT2 .The captures are shown as below.

VM=2.5V,PWM 50KHz

VM=2.5V,PWM 10KHz

VM=1.5V,PWM 10KHz

There are my questions:

1. When OUT1 is short to OUT2,is the device protected by OCP?

2. If the OCP is occurred, why is OCP released so fast(PWM50KHz:6.3us; PWM10KHz:9.2us)?

3. Why is the time between pulse to pulse(IOUT) changed following PWM frequency?

Thanks!

Jason wei