QC3.0 Powerbank Circuit Schematic - Page 1
Forum section: electronics / projects

author: redgear
author_rank: Frequent Contributor
timestamp: October 30, 2019, 07:55:29 am
content: I am looking at the Injoinic IP5328 to be used in my powerbank project. The datasheet has a reference schematic and I have doubts if it is complete. I am attaching the schematic below, while there is a terminal for the VBAT+, the connection for the negative terminal of the battery is nowhere mentioned.I want to use a different battery protector, How do I design the circuit in that case? Should I connect both the output from both MOSFETs (charging and discharging) to the same terminal(VBAT+)?If the image is not clear, I am also attaching the Datasheet PDF but it is available only in Chinese and I have been using Google Translate to read it.

author: jhpadjustable
author_rank: Frequent Contributor
timestamp: October 30, 2019, 09:24:10 am
content: It's safe to assume you connect the negative side of the battery to ground. There isn't a whole lot of pressure to get datasheets right when nobody knows how long the flavor-of-the-month will run. Not very helpful for young players, I'm sure.The protection board is intended to sit between the battery and its load. The MOSFETs on the protection board are intended to be connected in series so that they can pass or block current both to and from the battery.The battery and its protection board should be considered one unit, with a V+ terminal and a V- terminal that you can charge and discharge just as you would the battery alone, but safer. Typical application below.

author: redgear
author_rank: Frequent Contributor
timestamp: October 31, 2019, 05:23:26 am
content: Quote from: jhpadjustable on October 30, 2019, 09:24:10 amThank You! Wrt to above schematic, the negative terminal from the protection board should be connected to EPAD, right? Datasheet mentions EPAD as Power Ground and AGND as Analog Ground. What components should I ground to the AGND?

author: viperidae
author_rank: Frequent Contributor
timestamp: October 31, 2019, 05:48:29 am
content: Have a look at the bottom right of page two of the PDF you attached. It shows the battery negative connected to ground

author: redgear
author_rank: Frequent Contributor
timestamp: October 31, 2019, 08:27:09 am
content: Quote from: viperidae on October 31, 2019, 05:48:29 amThank You for pointing it out!Also, I just noticed in the image I attached EPAD is again grounded with a thicker trace.

author: redgear
author_rank: Frequent Contributor
timestamp: October 31, 2019, 09:06:48 am
content: I have to create a custom Symbol for the IP5328P in Kicad, can I use the same pin positions as in the image below? Are all pins except, BAT, VIN and VING output pins?

author: jhpadjustable
author_rank: Frequent Contributor
timestamp: October 31, 2019, 09:59:34 am
content: In general, connect all grounds together at the chip.Quote from: redgear on October 31, 2019, 09:06:48 amI'm lazy. I don't use the ERC function. So I just set everything that's not obviously logic or power to "passive" and call it a day.

author: Purduephotog
author_rank: Regular Contributor
timestamp: December 27, 2019, 02:18:36 am
content: A different model of this chip was (is) used in the Aukey/Anker 20,000 mah pack, and it did NOT have an NTC on it. Pack overheated while charging and fried the chip.There are PCBs on Ali with the chip you're talking about. Construction seems good; I've got it sitting and charging said dead pack right now, but it's only pulling 5V (2.5A). Don't know if that's a limit of the charger I'm using or not.I'm looking for a case for it, so if you come across one or create an STL please let me know.