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Products using MSP430

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#81 maelli01


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Posted 19 December 2015 - 06:27 PM

Bike light follow-up: reverse engineering time!


here is my almost complete circuit diagram.


IC1 is a voltage regulator: 2.5V, exact type I could not find out. Only the MSP runs on the regulated voltage, all the rest runs from the raw battery voltage.


Voltage divider R2 1M / R3 330K measure the battery voltage (some microamps get lost here)


LED2 and 3 are indicator (red/green)


LED1 is the power led


PWM is 20kHz, coming from pin 11 of the MSP.

Main switch is a Si4562, N and P channel 20V 5A mosfet. Inductor is 100uH.

Instead of using only the upper fet, they alternately switch on the upper / lower FET, avoiding one diode voltage drop, increasing effiency.

The circuitry around IC3 (a weird CMOS 4572) creates a small dead time (less than a microsecond) to avoid cross-conduction.

Note the resistors in the signal path ;-) 


They managed to regulate the LED current without a shunt resistor. Took me some time to find out how:

The voltage across the inductor is low-pass filtered, R14 390k / C4 0.1u, then fed into the MSP. Of course the DC-part of the inductor voltage depends on the current flow.

Pretty clever. The regulation is rather slow (ramp-up of current is so slow it is actually visible).


The circuitry around Q8 and Q9 takes care of the battery charge turn on/off. Input is from a wall-wart adaptor which is 500mA constant current type.

R10/R11 tell the MSP that external voltage is present.



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#82 pneumatics


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Posted 22 December 2015 - 09:09 AM

Nice work reverse engineer  :)

I'm not that much familiar with buck/boost converters. So I could not understand the inductor part. So we will leave it aside for the time  :D.

I have a question. The light has 4xAA cells, right? So can we tap from 3V (ie 2xAA) point and power the MSP? I'm (planning to) doing that in my working project. I dont know whether it is correct. The drawback i'm seeing  is that the battery may drain unequally. But uA and nA counts for Alkaline cells?

#83 maelli01


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Posted 26 December 2015 - 09:30 AM

sure  you can power an MSP430 from 2 AA cells. The unequal power drain should be manageable for a hobby project. 

However, for a "product" it is probably not a too good idea: 

- what happens when inserting / removing batteries?

- 2 cells discharged during months, 2 others not, might be o.k. for alkalines, but for long term using Nimh? I do not know.

- The MSP can use the internal reference for battery voltage measurement. You have to check the datasheet whether the 1.5V reference

works when 2 cells are at the end of life.

- you might also check for wrong polarity. The german clever designers solved this issue mechanically. It does not give contact when in wrong direction.

#84 vinicius.jlantunes


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Posted 04 February 2016 - 01:32 AM

I was watching Dave Jones video about the smart tweezers I've been wanting to buy, and it has got an MSP430 in there.

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#85 agaelema



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Posted 01 March 2016 - 04:17 PM

Teardown Tuesday: Kwikset SmartCode Lock





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#86 pneumatics


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Posted 11 March 2016 - 01:41 PM

Nice find  :goodjob:


There you see an MSP430G2231. I did not figure out what it does.


Looks like some ADC and digital out functions

#87 chicken


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Posted 22 May 2016 - 10:08 PM

Philips Hue Tap, a wireless light switch without battery, featuring a MSP430FR5730
Attached File  Philips Hue Tap FR5730.PNG   485.2KB   16 downloads

Teardown by Adafruit, with the MSP430 discovered at the 15 minute mark.

This device doesn't have a battery, but uses a mechanical, relais-like component to generate power when the user pushes buttons.
Attached File  Philips Hue Tap switch.PNG   44.97KB   9 downloads
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#88 bluehash


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Posted 23 May 2016 - 12:03 AM

Now that is some cool usage of energy harvesting. Thanks @chicken.

43oh - MSP430, TivaC, ARM-Sitara and C2000 Discussion, News, Projects and Hacks



#89 chicken


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Posted 23 August 2016 - 09:54 PM

Here's a MSP430F413 in a cheap (< US$100) radar speed gun

Attached File  radar_gun_alex_udanis_opened_-_1.jpg   62.29KB   14 downloads



I'm surprised how little analog and digital processing there is in this product.. I guess all the RF magic happens inside the transceiver module (which is available at Mouser for $50).

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#90 chicken


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Posted 25 January 2017 - 05:53 PM

Another MSP430, this time it's a MSP430FR5739 running the Ring "smart" doorbell :rolleyes:

Attached File  RingMSP430.PNG   406.06KB   1 downloads


The full teardown is documented here:



I was a bit surprised to only have a "lowly" MCU in a device that streams video over WiFi. But it looks like a specialized IC by Omnivision (OV788) and the WiFi module (GainSpan GS2011M) do the grunt work. The MSP430 probably just waits for someone to press the button and then turns on LED driver, camera and WiFi. See this dev kit by the vendor of the WiFi module.


Attached File  GS2011 Video.PNG   30.74KB   1 downloads

The wonders of integration.


TI has a similar app note pairing the OV788 with a CC3200.





#91 chicken


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Posted 10 February 2017 - 08:44 PM

A MSP430F415 in a cheap fingertip oximeter from AliExpress

Attached File  Oximeter box.jpg   48.79KB   4 downloads

Attached File  Oximeter.PNG   459.82KB   4 downloads


Teardown here: http://www.kean.com.au/oshw/oximeter/


I wonder if that nicely labeled JTAG header is still functional.

Attached File  Oximeter jtag.PNG   78.48KB   4 downloads


With 16K Flash and 512 bytes of RAM, this MCU is comparable to the MSP430G2553. Energia on an oximeter anyone?

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#92 Fmilburn


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Posted 10 February 2017 - 09:47 PM

It is interesting that you posted this as I recently gave some thought to building one of these. TI has a number of reference articles about them, e.g. http://www.ti.com/tool/TIDA-00311
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#93 maelli01


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Posted 21 February 2017 - 09:30 PM

Hioki multimeter MSP430F449





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