Hi JohnC,

EMU_E201 only applies to xG1 devices.  It does not apply to anything that follows like xG12, xG13, and xG14.

John

Hi JohnC,

EMU_E201 only applies to xG1 devices.  It does not apply to anything that follows like xG12m xG13, and xG14.

John

Hi JohnC,

Is it safe to erase/write flash up to the IM32 device's specified maximum temperature of 125 C?

Hi JohnC,

Is it safe to erase/write flash up to the IM32 device's specified maximum temperature of 125 C?

Hi Evangelos,

I'm afraid the QFN adapter you are using is fundamentally the source of your problem. It's causing you to connect things to the device in a way that runs counter to good circuit design and construction practices.

The trouble here is with all those capacitors on the corner of your board. I know what you've soldered might appear to look like what we do on our Starter Kits in terms of using the same decoupling capacitors values, but it doesn't match our design in any way that would lead to a functional circuit.

I suspect the issue here is two fold:

1. All of the decoupling capacitors, whether it's those connected to AVDD or IOVDD and especially those connected to DECOUPLE and DVDD are expected to be as close to the device as possible, i.e. comfortably less than 1 cm away. The collection of radial-leaded electrolytic capacitors bunched together on the corner of an adapter board that looks to be over 2 cm away from the device (and probably more like 4 cm when you include the lead lengths) is not conducive to proper operation.
    
2. I sincerely doubt that the actual capacitance SEEN at the DECOUPLE pin on the EFM32PG1 device in this setup is the mandated 1 µF that goes directly to ground. As this is critical to proper operation of the core voltage regulator, the fact that you are seeing an actual ramp to 2.2V on the pin tells me that something is very, very wrong.
    
3. I suspect the same probably applies if you are trying to use the DCDC, which is especially sensitive to the inductance seen on the VREGSW pin.

As I said, the QFN adapter is not helping you because it is resulting in a circuit layout that does not provide proper decoupling of the power supplies nor does it permit the DCDC converter to operate the way a properly constructed circuit would allow (and for which we have simulated and characterized the design).

It also looks like you haven't consulted our relevant application notes which provide guidance on how your hardware should be designed. Let me refer you to:

1. AN0002.1: EFM32 and EFR32 Wireless Gecko Series 1 Hardware Design Considerations, which provides an overview of how the power supplies should be connected and decoupled, among other things.
    
2. AN0948: EFM32 and EFR32 Series 1Power Configurations and DC-DC, which goes into detail on the use of the on-chip DC-DC converter.

At this point, I think you would really be better off getting a small PCB manufactured that follows our rules for powering and decoupling the device. You could still go with a breakout type of design as the QFN adapter provides (I've worked with a customer who was successful doing this once before), but the key would be that you would provide the necessary passive components for powering the device on the PCB using surface mount components that are placed as close to the pins to which they are connected as possible.

I don't think you will be successful if you persist in trying to use the QFN adapter, but if want to give it another try, follow the guidance in section 3.2 of AN0948 for configuring the device for operation WITHOUT the DCDC converter. I still don't know how you will manage a proper connection to DECOUPLE with a radial capacitor. It just runs counter to all of our guidance about this capacitor being as close to the device as possible with traces that are only as long as necessary to connect the capacitor to ground and meet component placement guidelines for manufacturability. However, you would be eliminating a major variable that might be a source of your problem.

John

Hi Evangelos,

I'm afraid the QFN adapter you are using is fundamentally the source of your problem. It's causing you to connect things to the device in a way that runs counter to good circuit design and construction practices.

The trouble here is with all those capacitors on the corner of your board. I know what you've soldered might appear to look like what we do on our Starter Kits in terms of using the same decoupling capacitors values, but it doesn't match our design in any way that would lead to a functional circuit.

I suspect the issue here is two fold:

1. All of the decoupling capacitors, whether it's those connected to AVDD or IOVDD and especially those connected to DECOUPLE and DVDD are expected to be as close to the device as possible, i.e. comfortably less than 1 cm away. The collection of radial-leaded electrolytic capacitors bunched together on the corner of an adapter board that looks to be over 2 cm away from the device (and probably more like 4 cm when you include the lead lengths) is not conducive to proper operation.
    
2. I sincerely doubt that the actual capacitance SEEN at the DECOUPLE pin on the EFM32PG1 device in this setup is the mandated 1 µF that goes directly to ground. As this is critical to proper operation of the core voltage regulator, the fact that you are seeing an actual ramp to 2.2V on the pin tells me that something is very, very wrong.
    
3. I suspect the same probably applies if you are trying to use the DCDC, which is especially sensitive to the inductance seen on the VREGSW pin.

As I said, the QFN adapter is not helping you because it is resulting in a circuit layout that does not provide proper decoupling of the power supplies nor does it permit the DCDC converter to operate the way a properly constructed circuit would allow (and for which we have simulated and characterized the design).

It also looks like you haven't consulted our relevant application notes which provide guidance on how your hardware should be designed. Let me refer you to:

1. AN0002.1: EFM32 and EFR32 Wireless Gecko Series 1 Hardware Design Considerations, which provides an overview of how the power supplies should be connected and decoupled, among other things.
    
2. AN0948: EFM32 and EFR32 Series 1Power Configurations and DC-DC, which goes into detail on the use of the on-chip DC-DC converter.

At this point, I think you would really be better off getting a small PCB manufactured that follows our rules for powering and decoupling the device. You could still go with a breakout type of design as the QFN adapter provides (I've worked with a customer who was successful doing this once before), but the key would be that you would provide the necessary passive components for powering the device on the PCB using surface mount components that are placed as close to the pins to which they are connected as possible.

I don't think you will be successful if you persist in trying to use the QFN adapter, but if want to give it another try, follow the guidance in section 3.2 of AN0948 for configuring the device for operation WITHOUT the DCDC converter. I still don't know how you will manage a proper connection to DECOUPLE with a radial capacitor. It just runs counter to all of our guidance about this capacitor being as close to the device as possible with traces that are only as long as necessary to connect the capacitor to ground and meet component placement guidelines for manufacturability. However, you would be eliminating a major variable that might be a source of your problem.

John