TPS2660: TPS26601 Issue about SHDN/

Part Number:TPS2660

Hi.

I have a question about SHDN/ working.

1. Load is about 800mA

2. First Start up is OK

3. SHDN/ pin is set LOW, VOUT is OFF. This working is OK.

4. But SHDN/ pin is set HIGH, VOUT is sitll OFF and FLT is activated.

5. And then if SHDN/ pin is set LOW -> HIGH after 8~10 seconds, VOUT is ON.

Why this working is occurred?

Please let me know how to fix this.

Thanks.