LT1932_ LED Driver Behavior

Dear Sir

We have used LT1932 to drive 20MA single LED from CR123A Li-ion Battery. We are facing the following issues:

1) Some of the board functions satisfactory but after few days of testing the LED stays at Full Brightness & we are not able to change the brightness using PWM at shutdown pin.

2) In some of the boards, the small residual voltage (a small amount of current is passing at low ) has observed at the LOW condition. (LED Lit mildly)

3) We have implemented a Zener diode (open string condition) & soft start circuit as recommended in the datasheet.

4) The PWM freq is 5KHz & Rset is set at 20mA

5) We also wanted to achieve uA steps for NVIS mode but max we can achieve is ~1.18mA

 Request you to provide the necessary inputs if any & If required pls suggest suitable P/N.

Thanks & Regards

Chirag Naik

[edited by: JValeriani at 8:02 PM (GMT 0) on 9 Oct 2019]
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