Integrated Circuit Identification Help?

[Deltatango]

I have one of those small (0.28 inch) voltmeters that are all around, I wonder if anyone has identified its IC used as all the ones I have seen have no markings.

Yes I know buy another as they are cheap, got one that is duff, regulator gets hot. Figure its either a PIC chip or some TI copy.

Any ideas ??

Thanks from David

 

[ELECTRONICIENSENIOR]

A photo ???
And pcb top - bottom

 

[SWRmeter]

Most any 8 bit uC could do the job. So there might be multiple solutions out there in the market. Need more information to be able to specifically identify a specific one, if it IS a standard uC at all. Regulator getting 'hot' is relative, but also dependent on the software the uC is programmed with, if it is a uC at all and not a dedicated chip.

 

[Deltatango]

I enclose the pictures requested, if they are some simple PIC chip thing then OK I give up and just salvage parts, but if it is a chip that has a number I would be interested. I know that many IC's that have emerged from China are from Texas Industries dating back to the 1960's then were sold to now defunct European companies of long ago, which have been copied and reused in interesting ways.

Thanks for any help David

 

[andre_luis]

Did you even make a survey on what pins are the VCC/GND, Reset, etc... ?

 

[Deltatango]

Sadly No it had blown up, I know it works on 3 volts and the regulator gets over hot plus must be multiplexed, as there are hundreds if not thousands of these meters around thought that some other person may have explored them before as happens.

Will get and check the power pins at least........

David

 

[andre_luis]

These key pins give at least an indication of what microcontroller/chipset is it, or alternativelly, which IC could replace it if applicable.

 

[barry]

Replacing a microcontroller without having the code to program it with is useless.

 

[KlausST]

Hi,

For multiplexing yor IC needs to be able to drive ROWs and COLUMNs.
For your 3 digit x 8 LEDs the ROW driver needs to be able to drive up to 8 LEDs.
This means if you want a LED current of 15mA, then the row driver needs to drive up to 8 x 15mA = 120mA.
A typical microcontroller can't do this. (Unless you spend other electronic parts which act as drivers .. and needs a lot of PCB space)

Even worse:
With multiplexing you lose brightness.
If you want to compensate for a 1:3 mux rate you need to multiply the LED current by 3.
So 120mA become 360mA.

Klaus

 

[ELECTRONICIENSENIOR]

Perhaps TITAN MICRO ELECTRONICS could have such a part like that :

TM1616 Datasheet(1/15 Pages) TITAN | LED

LED 驱动控制专用电路TM16161©Titan Micro Electronicswww.titanmec.comVer1.1特性描述TM1616是LED（发光二极管显示器）驱动控制专用电路，内部集成有MCU 数字接口、数据锁存器、LED 高压驱动等电路。本产品性能优良，质量可靠。主要应用于VCR、VCD、DVD 及家庭影院等产品的显示屏驱动。采用SOP16和DIP16的封装形式。 Datasheet search

html.alldatasheet.fr

https://fr.aliexpress.com/i/1005004406828514.html?gatewayAdapt=glo2fra

http://aitendo3.sakura.ne.jp/aitendo_data/product_img/ic/LED-driver/TM1651_%20V1.2/TM1651_V1.1_EN.pdf

 

[FvM]

You are showing a LED driver with SPI interface. The IC in questions is either a dedicated meter chip or a uC.
Current consumption of the voltmeter module is about 10 mA according to advertizing. So it could use a general purpose uC. There must be however some kind of segment current regulation, e.g. additional resistors below the LED part. Continuity test of the circuit can show if all LED pins are directly connected to IC or additional resistors are involved.

--- Updated Feb 14, 2023 ---

Presonally I would expect a dedicated meter ASIC, but not sure.

 

[ELECTRONICIENSENIOR]

Yes I know it is not exactly the same, I would only say that this silicon maker acts in this domain, with many references, for ex TM1637, 1638, 1639, 1640 and TM707 and 708 analog to digital converters. It should be an idea to visit their sites

LED Display Drivers | Nixie Tube Driver/LED Driver | LCSC

LED Display Drivers are available at LCSC Electronics. LCSC offers inventory, prices, datasheets for LED Display Drivers.

www.lcsc.com

https://www.win-source.net/manufacturer/shenzhen-titan-micro-electronics-co.-ltd..html

Titan Titan Micro Electronics Co., Ltd. in Shenzhen, Guangdong, China - Company Profile

Titan Titan Micro Electronics Co., Ltd. - is a leading Exporter of digital photo frame , , from Shenzhen, Guangdong, China

www.tradeindia.com