Freescale USB Development Board USB-KW40Z User’s Guide, Rev. 0, 10/2015

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Freescale Semiconductor, Inc.

USB-KW40Z development board

Figure 5. USB-KW40Z block diagram

4.2.1

RF performance and considerations

The USB-KW40Z board’s integrated transceiver includes a 1 mW nominal output power PA with internal

voltage controlled oscillator (VCO), integrated transmit/receive switch, on-board power supply regulation,

and full spread-spectrum encoding and decoding. Key specifications for the MKW40Z160 SoC are:

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Nominal output power is set to 0 dBm

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Programmable output power from -20 dBm to +5 dBm at the MMCX, no harmonic trap

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Typical sensitivity is -102 dBm (@1% PER for 25 °C) at the MMCX (802.15.4)

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Typical sensitivity is -91 dBm (@1% PER for 25 °C) at the MMCX (BLE)

•

Frequency range is 2360 to 2480 MHz

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Differential bidirectional RF I/O port with integrated transmit/receive switch

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Meander printed metal antenna for a small footprint, low cost design

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Uses a minimum number of RF marching components and external 50:100 balun

An external 50 (bal): 100 (unbal) balun connects a single-ended 50 ohm port to the differential RF port of

the MKW40Z160 SoC’s transceiver. The layout has provision for out-of-band signal suppression

(components L3 and C20) if required. Figure 6 shows the typical topology for the RF circuitry. The RF

connector J4 has been included in the design for measurement purposes and is used as a DNP.