Battery Charging Circuit with Dynamic Path Management IC - Page 1
Forum section: electronics / projects

author: ataradov
author_rank: Super Contributor
timestamp: January 06, 2019, 08:44:00 pm
content: I recently had to deal with a dead Hantek 2D72 scope, and the dead IC was H&M Semi HM4052. It is an IC from some Chinese company, but the functionality is "Switched Single-Cell Li-Ion Battery Charging Circuit with Dynamic Path Management". It is available in SO-8 package.Essentially it is a device that has input voltage (USB typically) and a battery voltage. And it produces regulated fixed output voltage. If input voltage is applied, then it is used to produce the output and also to charge the battery. If only battery is present, then it is used as an input to the boost converter.Here it is in Chinese datasheethttp://hmsemi.com/downfile/HM4052.PDF.The question is - are there equivalent in functionality ICs from more obtainable vendors, but in the same SO-8 or other small pin count and easy to solder package?I can find some equivalent ICs from likes of TI and Maxim, but they are overly complicated (with I2C interfaces) and only available in 24-32 pin packages that are hard to solder by hand.Anyone aware of closer equivalents?Come to think about it, this is exactly what portable power banks do. I guess I need to watch a few of Big Clive's videos now.

author: SiliconWizard
author_rank: Super Contributor
timestamp: January 07, 2019, 05:51:12 pm
content: This is an impressively to-the-point and very simple to use IC. Is the output voltage nominally 3.4V? (Seems so but I have a hard time with the datasheet.) Is it produced by a buck-boost switching regulator? (I'd suppose so, but again this is not very clear. Could it be a buck reg only? In which case obviously the output voltage would not be regulated when on battery only and its voltage drops below 3.4V...) Would be nice to know for sure, because there are very few charger ICs with integrated buck-boost regulators. Damn, we should learn chinese I guess. Google translate didn't help a whole lot, or maybe the datasheet is too frugal.Anyway, I've looked too and frankly haven't found anything close to this IC and as simple to use either. Yes most of them are QFNs with exposed pads.I guess you have also looked at Analog Devices/Linear? (I have looked a bit and the situation seems similar.)You could take a look at MP:https://www.monolithicpower.com/en/products/battery-management.htmlthey have a bunch of interesting power-related ICs and a lot are available from the usual distributors. After a quick look, I haven't found anything close to your requirements either, but they have many ICs so you may find something.As a last resort, you may consider designing a small PCB to solder on top of the SO8 footprint and use more readily available ICs, but I don't know if that would be worth the hassle.

author: ataradov
author_rank: Super Contributor
timestamp: January 07, 2019, 05:58:17 pm
content: I assume it is buck-only. In the device nothing depends on this voltage being stable, so it is hard to tell. The IC I have is obviously dead.The nominal output voltage is around 3.9 V (according to graphs).I just put diode or from USB and the battery. No charging for me, but the scope works from both USB and the battery now.

author: laurentiumarian
author_rank: Newbie
timestamp: November 27, 2019, 10:51:46 am
content: HI, It seems I have the same problem. Are you please so kind to tell me how you did it? Thanks

author: ataradov
author_rank: Super Contributor
timestamp: November 27, 2019, 05:53:19 pm
content: I really don't remember the details. But the ICs are actually available. They are called ETA6002 and here is one sourcehttps://www.aliexpress.com/item/32825837308.htmlThere may be others with smaller quantity.