Author Topic: switching IC identification?  (Read 282 times)

0 Members and 1 Guest are viewing this topic.

Offline iXod

  • Regular Contributor
  • *
  • Posts: 188
switching IC identification?
« on: August 13, 2018, 12:33:21 pm »
The manufacturer of this product has abraded off the number of this SMD-8 switching device.

It's in a 2-LED flashlight, one flood and one spot. Pressing the latching pushbutton once turns on the flood LED. Pressing the pushbutton again turns it off. If it is pressed again within a few seconds the spot LED illuminates; if the pushbutton is not pressed within that time period, pressing it again turns on the flood LED again.

Based on the delay between successive "ON" presses of the pushbutton, the device enables one of two outputs, turning on one or the other LED.

The only cap is in parallel with a resistor creating this time constant.

Anyone know what part number this switch device might be?

Schematic of the circuit follows. (Transistors--A13sHB--are draw intentionally vague; don't know if they're BJTs or FETs. Anybody know?) Power is a single 18650 cell.

Thanks.
« Last Edit: August 14, 2018, 02:49:13 am by iXod »
 

Offline amyk

  • Super Contributor
  • ***
  • Posts: 5777
Re: switching IC identification?
« Reply #1 on: August 13, 2018, 12:47:54 pm »
Your schematic is messy enough that it doesn't make much sense.

A1sHB (not A13sHB) are SI2301DS MOSFETs.

There are so many of these that your best bet is to Google "LED手电 IC" and just go through the results one-by-one for something matching.
« Last Edit: August 13, 2018, 12:50:14 pm by amyk »
 

Offline iXod

  • Regular Contributor
  • *
  • Posts: 188
Re: switching IC identification?
« Reply #2 on: August 14, 2018, 01:40:35 am »
Schematic is readable for anyone interested.

This IC has nothing to do with LED driving. LED current is set by transistors and series resistors.

This IC performs solely a switching function.

Thanks for your input.
 

Offline Benta

  • Super Contributor
  • ***
  • Posts: 1496
  • Country: de
Re: switching IC identification?
« Reply #3 on: August 14, 2018, 02:04:31 am »
Probably a small 8-pin MCU. They're so cheap nowadays that making a custom IC doesn't make sense.
 
The following users thanked this post: iXod

Offline iXod

  • Regular Contributor
  • *
  • Posts: 188
Re: switching IC identification?
« Reply #4 on: August 14, 2018, 02:29:24 am »
Thanks for your reply.

If it's a cheap MCU, why erase the ID from the chip? I mean, if it's programmed it wouldn't matter if I did know the IC number, I wouldn't have the code.

And if custom IC, replacement not available so no reason to hide ID.

This why I still suspect a common (not custom) part number.

Thanks.
« Last Edit: August 14, 2018, 02:51:04 am by iXod »
 

Offline amyk

  • Super Contributor
  • ***
  • Posts: 5777
Re: switching IC identification?
« Reply #5 on: August 15, 2018, 11:59:19 am »
Schematic is readable for anyone interested.

This IC has nothing to do with LED driving. LED current is set by transistors and series resistors.

This IC performs solely a switching function.

Thanks for your input.
There are special ICs that do just this switching function, and they are designed for use in LED flashlights. I believe I've seen one mentioned before in a bigclivedotcom video. It's not a microcontroller but an ASIC, because at the volumes these are made, a tiny amount of custom logic is cheaper. They have linear current regulators but in this case the manufacturer added the transistors to drive higher current LEDs.
 

Offline GadgetBoy

  • Regular Contributor
  • *
  • Posts: 71
  • Country: ca
Re: switching IC identification?
« Reply #6 on: August 15, 2018, 12:03:38 pm »
It's most likely a pic of some unknown provenance, judging by the placement of the power rails.

Sent from my ONEPLUS A3000 using Tapatalk

 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf