Smart Bluetooth Forum Discussions

Hi I know this thread is from a couple of years back: 20737S VBat short to GND​

but was there ever a resolution as we have had 2 chips fail?

One shorted out vBat to GND and the other suddenly pulls low the SPI and serial lines meaning it fails to communicate.

Thanks

Dear all,,,

I have been developing our application (barcode reader) with CYW20706-A2 Version.

I'm going to do tuning the external crystal (Main Clock / 24MHz) to measure good RF perfromance.

For example, The attached file is the external crystal selection and tuning guide for Cypress BLE (PSoC, PRoC).

For Broaccom BT Product, if there is any crystal tuning guide, pls, let me know hot to do tuning the external crystal (Main Clock / 24MHz).

Thanks,

Best Regards,

Philip Choi

We have been using the BCM20737S (SiP module).

Now we're trying to migrate to using the CYW20737A1KML2G (SoC) with external EEPROM, crystal, antenna, etc. and I'm using the BCM920737_LE_TAG4 board as a starting point for the external components used.

We plan to use the CYW20737 chip at 1.8V.

Physical size is important.

1.  Is the BCM920737_LE_TAG4 board a good candidate for finding other needed components?

2.  The 24FC512-I/ST used on this board is 3x6.4mm.  Are there other smaller parts that can be used instead?

For example, the 24AA512T-I/CS17K is probably the smallest part from the same family, but the "AA" part means it is only rated at 100kHz I2C at 1.8V whereas the original is rated at 400kHz I2C.

If I try to use another I2C 512kbit EEPROM Microchip family or something from On Semiconductor, ST, Toshiba, etc. would that cause a problem?

Every now and then (very rarely), we have this issue where a download will fail with no apparent reason and then we would not be able to

download the firmware anymore. We have to bring the part into download mode by holding the SDA high and then do the recovery procedure.

From looking at other posts with similar problems, I can see two problems that could lead in download failure: 1) I2C line load or interference

and 2) having a sudden disconnection of the cable or power down. I assume here that the right 3.3V cable is used.

In the post: Rebooting/Recovery of a BCM20737S **HELP**  the answer given states that it common to have EEPROM corrupted if you download and

test new firmware. I am wondering if there is an explanation what could cause something like that, assuming we don't have I2C and power problems.

Is this something that we can avoid or this is something out of our control that could happen anytime?

Thanks

Kostas

HI, I'm working with BCM 20737. The application uses the DEEP SLEEP mode, waking up via GPIO. It works fine, but now I need to recognize a wake up from DEEP SLEEP from a POR (Power On Reset) : Both stars with a bootstrap and passes through an APPLICATION_INIT. My question is There is a uController register I can check in order to recognize the difference ? Can You provide any axeample ?

Thanks,

Giuseppe

Hi,

I looked at the below URL and it says that the chip is WICED SMART READY.

http://japan.cypress.com/products/automotive-bluetooth​

Is this programmable via Smart SDK?

Best,

Wataru

Hi,

I'm trying to understand how to layout this IC so that I get the best range possible but the instructions on the technical manual are nor very clear to me.

Are side A and D on the edge of the board or is the GND Plane on the edge of the board? If the GND plane is not the edge of the board then what should I do after that? Can I just extend this GND plane for the entire board?

Where there is the L indication for the GND plane the same does nor reach the edge of the keepout area. Why is that? What should be placed above this area?

Would someone have an example that has a good range with this IC (no external antenna)?