STM32L151C6 = Medium Density Device?

[parketny]

Posted on April 29, 2013 at 11:38

Hi All,

the reference manual is quite confusing regarding this question. Within most it is stated that the medium range devices have a flash range from 64 to 128KByte, while in one chapter this range is given from 32 to 128KByte (Cp. 14 Operational amplifiers).

1. I would assume that the 32kB Flash memory MCU is also a medium density device. Is that assumption correct?

2. Is the STM32L151CBU6 (128kB Flash) a medium oder a medium+ device?

Thanks for clarifying.

Regards,

Tobias

#stm32l151

[Tesla DeLorean]

Posted on April 29, 2013 at 13:35

Medium-density devices are STM32L151xx and STM32L152xx microcontrollers where

the program memory density ranges between 64 and 128 Kbytes.

Medium+ density devices are STM32L151xx, STM32L152xx and STM32L162xx

microcontrollers where the program memory density size is 256 Kbytes.

High-density devices are STM32L151xx, STM32L152xx and STM32L162xx

microcontrollers where the program memory density is 384 Kbytes.

[parketny]

Posted on April 29, 2013 at 14:56

Hi Clive,

I have read these notes in nearly every section of the reference manual, but not in the OPAMP section:

''Medium density devices are STM32L151xx and STM32L152xx microcontrollers where the Flash memory density ranges between 32 and 128 Kbytes.''

And well, if the 32kB devices are not medium density devices I can not find any information on this device within the reference manual, not even within the device id field:

DEV_ID(11:0): Device identifier

This field indicates the device ID.

0x416: Medium density device

0x427: Medium+ density device except devices in CSP64, BGA132 and

LQFP144 packages

0x436: Medium+ density device for devices in CSP64, BGA132 and LQFP144

packages

0x436: High density device

Despite your answer I am not convinced that the STML151C6 is a low density device. When having a look at the device overview (p.10/cp. 2.1) the 32kB version has the same peripherals as the ''bigger'' STM32L15xCx micros.

Tobias

[Tesla DeLorean]

Posted on April 29, 2013 at 16:03

What's important is to figure out what die your part has, you should perhaps examine the 16-bit word at 0x1FF8004C, to determine the flash size. A flash of 32KB would, I presume, qualify as a low density part.

[parketny]

Posted on April 30, 2013 at 14:36

I do not have a STM32L151C6 device yet. I am evaluating it at the moment.

I am not convinced that your presumption is correct, since I can neither find information for a low density device in the Flash module organization section nor within the embedded bootloader section of the reference manual. That's why I expect the 32kB flash device STM32L151C

6

to be a medium density device despite the fact that the reference manual tells me that the medium density devices begin with 64kB...

Tobias

[Tesla DeLorean]

Posted on April 30, 2013 at 15:44

I'm presuming the die in your part actually has 64KB of FLASH, with only half of it being tested. Check the device, then you'll know.

[parketny]

Posted on April 30, 2013 at 16:13

Ok, now I understand your point. But I expect that it should be possible to get a clarification of this issue before buying the ic, writing firmware and reading out the device flash size.

[Tesla DeLorean]

Posted on April 30, 2013 at 17:46

Then you'll need to dig up an ST rep or FAE and probe them. My due diligence process includes getting an eval board and understand parts before I select them. Trying to do a clean room design from the data/reference/programming manuals is fraught with problems.

The STM32F205 I have is marked as 256KB, it has 1MB on it. Chip marking and pricing stratification suggest there are more die variations than there actually are.

You are correct the PM doesn't describe the 32K variant, in the same way the F2/F4 PM's don't describe anything below 1MB, the lower rated parts being a subset.

An L1 part that really only contained 32KB would be a different die, and that's not documented anywhere. Again clarification from ST would be needed, as I'm not buying this part.