Arduino Pro Mini - two copies have different sleep currents

[Peabody]

So far, the only difference in performance that's been documented is the power-down sleep current.  And I don't usually mind using a cloned chip - I suspect I've never actually used a genuine FTDI chip.  But the MCU is a bit different.  If there's something that just doesn't work right, but it seems it ought to, could it be the fake 328P that's causing the problem?  So it becomes another thing you have to rule out that you shouldn't have to worry about.

But I would guess the counterfeits work ok for most things or issues would have been raised before.  When I tested the sleep current, it wasn't really the processor I wanted to test.  It was the rest of the Pro Mini board, and to make sure I hadn't messed up something when removing the regulator and LED.  And it was only when I received the second batch of Pro Minis from a different seller, which had been made with different parts in a different production run, but which also wouldn't sleep properly, that I began to suspect the processor.  So I suspect there are many people out there using these chips with no noticeable problem.

I wonder what's being shipped now from AliExpress, Bangood, and the large Ebay sellers.  My sellers were domestic US, and certainly not large, but could deliver in a week. SleemanJ reported receiving genuine parts on a recent order from TaoBao.  So I guess there's a possibility that this was a single production run, and new stuff will be ok.  Well, ok, just a possibility.

I still think we need Microchip to help find a reliable way for us to distinguish genuine from counterfeit.

[DrG]

Something put those bytes in there (as they are not 0xFF) and it almost certainly has to be the factory wafer ATE.

I think they are *NOT* a UID because Atmel, now Microchip don't *GUARANTEE* that they will be unique.  Obviously X,Y coordinates within a wafer will repeat, and over multiple batches the wafer number will repeat, so if the lot no. isn't guaranteed unique (i.e. due to limited code space of 6 alphanumerics, which probably also encodes the fab and line) they could reuse them, returning to the start when they run out of valid lot numbers for a particular fab/line.  Also, its a management issue - if they have to restart the wafer ATE partway through a run, do they *ALWAYS* guarantee to preset the last wafer no. used correctly?  It obviously benefits them for traceability to have a near-unique serial no. but I suspect the extra costs to publicly guarantee its a UID and make it so aren't insignificant.

If my suppositions are correct, the odds of finding a serial no. collision between current production genuine chips are vanishingly small, and although such collisions between current chips and old genuine chips are possible, your chances of finding one 'in the wild' are infinitesimal, mostly due to the small number of chips that will have survived in active use that are *NOT* in a dedicated application where the firmware will never be changed again.

I don't disagree with you although I am (literally) not sure about some of what you are saying based on my own limitations and lack of motivation to do many more hours of reading.

The problem, which we seem to be in agreement about, is that, beyond the signature bytes, the relevance of the values are undocumented. That does not mean that they can not be useful...subject to further examination. I think that is exactly what we are talking about with regard to identifying those chips that do not meet the low-power specs. If I had some Pro Minis that did not have something that looked like a UID (e.g. only FFs), I would avoid that chip or not choose to use it if I had a choice.

[HwAoRrDk]

I dumped the signature bytes from all the Arduino boards I own (or, at least, all the ones I could find ). One is a genuine Arduino Uno board, the others anonymous Uno clones. I've not had any problems with these clone boards - they've performed to expectations - but I've never done anything exotic with them that would expose them as potentially having non-genuine chips.

None of them are very recent, but I thought the data might be useful to see what typical clone board chips from prior years are like.

Genuine Arduino Uno R3, DIP-28
Markings:
1431
ATMEGA328P-PU
Boot signature dump:
      0001 0203 0405 0607 0809 0A0B 0C0D 0E0F - 0123456789ABCDEF
----------------------------------------------------------------
0x00: 1E42 95FF 0FD2 FF26 FF09 FF17 FFFF 5734 - .B•ÿ.Òÿ&ÿ.ÿ.ÿÿW4
0x10: 3431 3334 FF13 1C01 1702 1206 1306 FFFF - 4134ÿ.........ÿÿ

Clone Arduino Uno, LQFP-32
Markings:
MEGA328P
AU 1651
Boot signature dump:
      0001 0203 0405 0607 0809 0A0B 0C0D 0E0F - 0123456789ABCDEF
----------------------------------------------------------------
0x00: 1E9D 95FF 0FCE 0026 FF09 FF17 FFFF 5836 - ..•ÿ.Î.&ÿ.ÿ.ÿÿX6
0x10: 3134 3831 FF05 1B0D 1702 1208 1308 FFFF - 1481ÿ.........ÿÿ

Clone Arduino Uno, LQFP-32
Markings:
MEGA328P
U-PH
35473D
1752YSP
Boot signature dump:
      0001 0203 0405 0607 0809 0A0B 0C0D 0E0F - 0123456789ABCDEF
----------------------------------------------------------------
0x00: 1EAE 95FF 0FCE FF26 FF08 FF17 FFFF 5837 - .®•ÿ.Îÿ&ÿ.ÿ.ÿÿX7
0x10: 3734 3832 FF19 121D 1701 1209 1309 FFFF - 7482ÿ.........ÿÿ

[SilverSolder]

So far, the only difference in performance that's been documented is the power-down sleep current.  And I don't usually mind using a cloned chip - I suspect I've never actually used a genuine FTDI chip.  But the MCU is a bit different.  If there's something that just doesn't work right, but it seems it ought to, could it be the fake 328P that's causing the problem?  So it becomes another thing you have to rule out that you shouldn't have to worry about.

But I would guess the counterfeits work ok for most things or issues would have been raised before.  When I tested the sleep current, it wasn't really the processor I wanted to test.  It was the rest of the Pro Mini board, and to make sure I hadn't messed up something when removing the regulator and LED.  And it was only when I received the second batch of Pro Minis from a different seller, which had been made with different parts in a different production run, but which also wouldn't sleep properly, that I began to suspect the processor.  So I suspect there are many people out there using these chips with no noticeable problem.

I wonder what's being shipped now from AliExpress, Bangood, and the large Ebay sellers.  My sellers were domestic US, and certainly not large, but could deliver in a week. SleemanJ reported receiving genuine parts on a recent order from TaoBao.  So I guess there's a possibility that this was a single production run, and new stuff will be ok.  Well, ok, just a possibility.

I still think we need Microchip to help find a reliable way for us to distinguish genuine from counterfeit.

I wonder what these fake chips actually cost - maybe they are in range of the PADAUK processors, costing only pennies each? 

There is a place for compatible chips in the ecosystem, like Intel vs. AMD in the PC world...   but the chips need to be marked with what they actually are, rather than flying a false flag...

In a manufacturing situation you would probably want the "real thing" except for the lowest end consumer goods, unless the Aries chip somehow gets validated/tested and supplied with its own specs.


Another interesting thought is, there might be something the Aries chip actually does better than the Atmel one?  Maybe it can source or sink more current, or do well with some other parameter...  there's bound to be other differences between them in addition to the sleep current performance!

[HwAoRrDk]

I wonder what these fake chips actually cost - maybe they are in range of the PADAUK processors, costing only pennies each?

I would suspect somewhere in the region of $0.30. Clone Arduino Pro Mini boards sell for less than $2 on Alibaba, often nearer $1.50 in quantity. If you take into account that sellers are probably making their own small profit, say 10%, that means they're probably buying from the manufacturer for roughly $1.30 each. PCBs probably cost a few cents each, let's say 5c. All the supporting components are probably around 1 cent each - let's say $0.20 worth. Assembly costs are probably another few cents - call it $0.20. Add on another few cents for overheads, and we might have a price of $0.70 each. If the manufacturer is taking a 50% profit, that leaves less than $0.35 for the microcontroller.

[Doctorandus_P]

With another uC the STM32F103C8T6 which used to be popular in the "Blue Pill" boards is also plagued by dubious practices. There are currently at least 8 different clones of this chip, and if you buy the "blue Pill"boards from aliexpress / Ebay / China Direct they all have the string "STM32F103C8T6" on it, though often the ST logo is missing.
STM is the prefix for:  https://www.st.com/ But the chinese don't care about such details.

Each of those 8 manufacturers has their own prefix, and LCSC.com sells them all with the prefix of each manufacturer. Somehow these disapear on Ali / Ebay / China. There are known differences and incompatibilities between these look a likes, you never know which of the clones you get. More and more people are moving away from these boards for this reason.

The difference happened one or 2 years ago. Back then the price of these boars was around EUR 3.5, and now it dropped to below 2, but it's a price I am not prepared to pay.

There are several long threads with documentation about the STM32F103C8T6, including links to an external site with die pictures of several (maybe all?) decapped variants.

[cdev]

I have two that have the following code

MEGA328P
AU 1710

(no additional text on the chip)

Have no idea what the idle current is.

[NiHaoMike]

Another interesting thought is, there might be something the Aries chip actually does better than the Atmel one?  Maybe it can source or sink more current, or do well with some other parameter...  there's bound to be other differences between them in addition to the sleep current performance!

A good test to try would be to repeatedly write to the EEPROM until it starts to fail. I wouldn't be surprised if the clone fails way earlier than what the datasheet figures would predict.
https://hackaday.com/2011/05/16/destroying-an-arduinos-eeprom/

[Doctorandus_P]

It seems this post has reached Hackaday.
With links to youtube video's and die pictures.
The die has a "Aries" logo on it instead of "Atmel" (@08:20 on the 2nd video).

https://hackaday.com/2020/09/15/deep-sleep-problems-lead-to-forensic-investigation-of-troublesome-chip/

[DrG]

I wonder what these fake chips actually cost - maybe they are in range of the PADAUK processors, costing only pennies each?

I would suspect somewhere in the region of $0.30. Clone Arduino Pro Mini boards sell for less than $2 on Alibaba, often nearer $1.50 in quantity. If you take into account that sellers are probably making their own small profit, say 10%, that means they're probably buying from the manufacturer for roughly $1.30 each. PCBs probably cost a few cents each, let's say 5c. All the supporting components are probably around 1 cent each - let's say $0.20 worth. Assembly costs are probably another few cents - call it $0.20. Add on another few cents for overheads, and we might have a price of $0.70 each. If the manufacturer is taking a 50% profit, that leaves less than $0.35 for the microcontroller.

Your estimate is generally consistent (maybe a bit high) with this advertisement https://szaries.en.alibaba.com/product/60782607389-807067064/_Electronic_Components_atmega_328p.html?spm=a2700.icbuShop.41413.15.40fa769dCfBf3H

[TomS_]

Edit: Nevermind, already covered in Doctorandus_P's post

Haven't read the whole thread, but I just came across this video on YouTube. Very likely a high probability of a fake chip?

https://youtu.be/o0rEzcKYzGw

[Mecanix]

All parts used by the mass (popular ones) are cloned, not only by China but pretty much anyone/anywhere. Some even reported seeing those populars sold by authorized/licensed resellers for the price of a genuine. Trick to avoid being victim of this global incentives-hungry-phenomena is to avoid all parts that are "hyped" on the internet. Use/engineer with the equivalent from another manufacturer instead. I'd certainly avoid those 328 and other atmel duino thingy at all cost... regardless of where they come from

It is what it is...

[elecdonia]

I'm bumping this topic because I have several projects which use AVR devices: ATmega328P, ATmega324, ATmega644, ATmega1281, ATmega2560.

Some are used as "bare chips" in my own projects.

Others are "factory-installed" on a variety of Arduino-style boards including genuine original Arduino UNO, Chinese clone UNO-style boards, sparkfun RedBoards (UNO form factor), and adafruit Metro (UNO form factor). I also have a large quantity of Chinese clone Pro-mini and Nano style boards of various ages from recent back to 5 years old. Some of my Pro-mini boards cost <$4 USD each, leading me to suspect they do not contain genuine Atmel AVR chips.

My hoard of AVR devices provides a large variety of devices to explore. Several are guaranteed to be "genuine Atmel" because I purchased them as bare chips from Digikey 8-10 years ago, well before the Chinese began supplying huge quantities of (cheap) clone Arduino boards.

I plan to measure sleep currents and will obtain the entire 32 bytes of signature data from each AVR device.

Another item  I will measure is the frequency and stability of the 8MHz internal clock. I'm doing this because I frequently use the 8MHz internal RC oscillator in my projects. I wonder how much the accuracy/stability of the internal oscillator varies when comparing "genuine Atmel" to clone AVR chips?

Here are My first results from reading the entire 32 byte signature area from my AVR chips:

     Note: I edited “Lot#” and “Wafer info” after reading the Atmel app note

              This is from a genuine Atmel ATmega1284 I purchased from Digikey. 40-pin DIP package. Date code: 1940

Code: [Select]

AVR boot signature dump for ATmega1284
 Signature: 1E 97 06     OscCal: 90
Hex data:
  1E    90    97    FF    06    FF    FF    FF   
  FF    FF    FF    F7    FF    FF    57    39   
  36    31    32    36    FF    15    13    0F   
  17    01    12    FF    13    FF    FF    FF   

 Lot# 9W1662    Wafer info: 15  13  0F
           Chinese clone UNO board

Code: [Select]

AVR boot signature dump for ATmega328P
 Signature: 1E 95 0F    OscCal: AE
Hex data:
  1E    AE    95    FF    0F    E0    FF    26   
  FF    0A    FF    17    FF    FF    57    38   
  31    32    34    30    FF    0D    14    01   
  17    01    12    09    13    09    FF    FF 

 Lot: 8W2104     Wafer info: 0D 14 01
                 Chinese clone MEGA 2560 PRO board purchased in 2023

Code: [Select]

AVR boot signature dump for ATmega2560
 Signature: 1E 98 01    OscCal: 94
Hex data:
  1E    94    98    FF    01    FF    FF    FF   
  ED    FF    FF    F7    FF    FF    57    36   
  30    31    36    31    FF    16    15    0D   
  17    08    12    07    13    07    FF    FF 

 Lot# 6W1016    Wafer info: 16 15 0D
               Chinese clone NANO board      "DIY   more"      About 4 years old

Code: [Select]

AVR boot signature dump for ATmega328P
 Signature: 1E 95 0F    OscCal: AB
Hex data:
  1E    AB    95    FF    0F    DD    FF    26   
  FF    0C    FF    17    FF    FF    58    35   
  37    33    31    36    FF    12    0B    1D   
  17    01    12    06    13    06    FF    FF

 Lot# 5X3761     Wafer info: 12 0B 1D
                 Chinese clone Pro-mini board    "DIY more"   purchased about 4 years ago

Code: [Select]

AVR boot signature dump for ATmega328P
 Signature: 1E 95 0F    OscCal: A4
Hex data:
  1E    A4    95    FF    0F    C6    FF    26   
  FF    0A    FF    17    FF    FF    55    38   
  38    30    32    32    FF    10    06    06   
  17    01    12    09    13    09    FF    FF   

 Lot# 8U0822     Wafer info: 10 06 06
         Another Chinese clone Pro-mini board    "DIY more"   purchased about 4 years ago

Code: [Select]

AVR boot signature dump for ATmega328P
 Signature: 1E 95 0F    OscCal: 8A
Hex data:
  1E    8A    95    FF    0F    E3    FF    26   
  FF    08    FF    17    FF    FF    57    38   
  32    33    36    39    FF    0B    1B    14   
  17    01    12    09    13    09    FF    FF   

 Lot# 8W3296     Wafer info: 0B 1B  14
    So far, this next board has the only signature I’ve discovered yet where most of the bytes are 0xFF

            Another Chinese clone Pro-mini board      "The Simple"      purchased in 2023

Code: [Select]

AVR boot signature dump for ATmega328P
 Signature: 1E 95 0F    OscCal: C8
Hex data:
  1E    C8    95    FF    0F    FF    FF    26   
  FF    FF    FF    FF    FF    FF    58    FF   
  DF    FF    DF    FF    FF    FF    FF    FF   
  FF    FF    FF    FF    FF    FF    FF    FF

Lot#  X          Wafer info: FF FF FFThe only ASCII character in the 6 byte “Lot#” field is the letter “X” 
(The rest is  of this field is either 0xFF or 0xDF - not ASCII characters)
“Wafer info” is all 0xFF

[elecdonia]

I believe the lot codes *SHOULD* be ASCII.  They are six characters long in byte reversed pairs starting at location 0x0E.    Real Digikey 2020:

Code: [Select]

1E BA 95 FF 0F C6 00 26
FF 09 FF 17 FF FF 57 39
39 31 36 31 FF 01 29 1D
17 05 12 09 13 09 FF FF
has a lot code of '9W1916'. 
The wafer no. and die X,Y position (locations 0x15 - 0x17) are also informative

Did Atmel ever release any documentation about these reserved locations in the signature area?

    EDIT: Yes they did. See my newer post for details:
              https://www.eevblog.com/forum/microcontrollers/arduino-pro-mini-two-copies-have-different-sleep-currents/msg4799735/#msg4799735

Interesting: The “lot code” ASCII string is stored in “little endian” fashion (byte order reversed). This doesn’t surprise me because AVR machine code is also stored in flash as “little endian.”

I’m in the process of gathering signature dumps (all 32 bytes) from all of my AVR devices and Arduino boards.
So far I’ve identified only one board where most of the data is a string of 0xFF. It is a recently manufacturerd Chinese clone Pro-mini board labeled “The Simple.”

[elecdonia]

Did Atmel ever release any documentation about these reserved locations in the signature area?

Answering my own question: Microchip/Atmel technical article (summarized here):

Code: [Select]

​​​​​For Mega and Tiny T devices with “Serial number,”
  they have similar signature addresses for
  Lot Number, Wafer Number and X, Y coordinates.
 Byte Address --------- Description
    0x0E --------- Lot Number 2nd Char
    0x0F --------- Lot Number 1st Char
    0x10 --------- Lot Number 4th Char
    0x11 --------- Lot Number 3rd Char
    0x12 --------- Lot Number 6th Char
    0x13 --------- Lot Number 5th Char
    0x14 --------- Reserved
    0x15 --------- Wafer Number
    0x16 --------- Y-coordinate
    0x17 --------- X-coordinateThis section of signature data is 10d bytes in length.

 First 6 bytes:    ASCII text stored in “little endian” (bytes reversed)
                             ( addr 0x14 “reserved” )
 Last 3 bytes:    Wafer data (wafer #, X & Y coordinates)

Link to Microchip/Atmel technical article:
    https://microchip.my.site.com/s/article/Serial-number-in-AVR---Mega-Tiny-devices

[LC333]

    So far, this next board has the only signature I’ve discovered yet where most of the bytes are 0xFF

            Another Chinese clone Pro-mini board      "The Simple"      purchased in 2023

I've just ordered 10 of these marked "The Simple".  I had clean forgot about the prevalence of copied 328P chips as it's been a while since I've ordered complete PCBs like this, will check them when I receive them.

[Pacjunk]

I know this is an old thread, but I thought I would share my experience...

I have built several battery powered items over the years that use deep sleep, so I know my code is good. This particular system used one of the "The simple" type boards, which seemed to do things as expected. After only getting 3 weeks battery life for something that I expected to run for a year+, I pulled the thing apart looking for the issue. Once I had it down to the bare pro mini board, it was still taking 2.5mA in sleep. I know it was in sleep mode as it was doing the 8 second cycle as expected.

I tested the board with the suggested sketch and it showed lots of FF's. I managed to find a non-simple board in an old project and wired it up.
Same code is now 1.5uA in sleep!

So this post is really just to say, don't necessarily expect the 100-150uA sleep for these counterfeit chips. It can be much higher than that!

[SilverSolder]

Did Atmel ever release any documentation about these reserved locations in the signature area?

Answering my own question: Microchip/Atmel technical article (summarized here):

Code: [Select]

​​​​​For Mega and Tiny T devices with “Serial number,”
  they have similar signature addresses for
  Lot Number, Wafer Number and X, Y coordinates.
 Byte Address --------- Description
    0x0E --------- Lot Number 2nd Char
    0x0F --------- Lot Number 1st Char
    0x10 --------- Lot Number 4th Char
    0x11 --------- Lot Number 3rd Char
    0x12 --------- Lot Number 6th Char
    0x13 --------- Lot Number 5th Char
    0x14 --------- Reserved
    0x15 --------- Wafer Number
    0x16 --------- Y-coordinate
    0x17 --------- X-coordinateThis section of signature data is 10d bytes in length.

 First 6 bytes:    ASCII text stored in “little endian” (bytes reversed)
                             ( addr 0x14 “reserved” )
 Last 3 bytes:    Wafer data (wafer #, X & Y coordinates)

Link to Microchip/Atmel technical article:
    https://microchip.my.site.com/s/article/Serial-number-in-AVR---Mega-Tiny-devices

[FX: begging bowl in hand]  Would you be able to share a sketch that dumps the information to serial, or something like that?

[Peabody]

The sketch I use was provided by Kevin Darrah.  It works on the 328P.  I don't know about the other Atmels.

Code: [Select]

#include <avr/boot.h>
#define SIGRD 5
void setup() {
  Serial.begin(9600);
  Serial.println("");
  Serial.println("boot sig dump");
  int newLineIndex = 0;
  for (uint8_t i = 0; i <= 0x1F; i += 1) {
    Serial.print(boot_signature_byte_get(i), HEX);
    Serial.print("\t");
    newLineIndex++;
    if (newLineIndex == 8) {
      Serial.println("");
      newLineIndex = 0;
    }
  }
  Serial.println();
}

void loop() {
}