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KW40Z PA Issue

Discussion created by Like Li Employee on Jul 13, 2016
Latest reply on Aug 11, 2016 by wswong

My customer is trying to use the KW40Z  in their ZigBee products.

And they need to add external power amplifier and LNA to extend the RF Range for the product. However, they have encountered a problem on this part.

 

They use single antenna configuration and use only one GPIO PTC2 to control the TX/RX switch of the FEM (Front End Module).

Refer to the chapter 31 (FEM) and chapter 51 (ZLL) of the reference manual (Document Number: MKW40Z160RM Rev. 1.2, 10/2015):

Register/Field Name

Setting1 (Use TSM)

Setting 2 (Use FAD)

PTC2

Output GPIO (MUX=1)

MUX = 4

ZLL_FAD_CTRL Register:

FAD_EN

0

1

ANTX

0

0

FAD_NOT_GPIO

0

1

ANTX_EN

01

01

ANTX_HZ

0

0

ANTX_CTRLMODE

0

0

ANTX_POL

0

0

TSM Registers:

TSM_TIMING42

Have tried the following values with the above FAD Control Register value:

0x00000000

0xFFFFFFFF

0x01010101

0x03030303

0xFFFF0000

0xFFFF0303

0xFFFFFFFF

Base on the above settings, the PTC2 always stays low even when the KW40Z transmitting and receiving data.

Also the gpio pin mapping shown in page 1036 and page 1408 of the reference manual are not consistent.

 

 

 

 

Can anyone advise the correct setting to enable the TX/RX Switch pin (PTC2) for 802.15.4.

Thank you very much!

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