ST SPIRIT1 User Manual

SPIRIT1

Low data rate, low power sub-1GHZ transceiver

Features

■Frequency bands: 150-174 MHz, 300-348 MHz, 387-470 MHz, 779-956 MHz

■Modulation schemes: 2-FSK, GFSK, MSK, GMSK, OOK, and ASK

■Air data rate from 1 to 500 kbps

■Very low power consumption (9 mA RX and 21 mA TX at +11 dBm)

■Programmable RX digital filter from 6 kHz to 800 kHz

■Programmable channel spacing (12.5 kHz min.)

■Excellent performance of receiver sensitivity (- 120 dBm), selectivity, and blocking

■Programmable output power up to +11 dBm

■Fast startup and frequency synthesizer settling time (6 µs)

■Frequency offset compensation

■Integrated temperature sensor

■Battery indicator and low battery detector

■RX and TX FIFO buffer (96 bytes each)

■Configurability via SPI interface

■Automatic acknowledgement, retransmission, and timeout protocol engine

■AES 128-bit encryption co-processor

■Antenna diversity algorithm

■Fully integrated ultra low power RC oscillator

■Wake-up on internal timer and wake-up on external event

■Flexible packet length with dynamic payload length

■Sync word detection

■Address check

■Automatic CRC handling

■FEC with interleaving

Datasheet — preliminary data

QFN20

■Digital RSSI output

■Programmable carrier sense (CS) indicator

■Automatic clear channel assessment (CCA) before transmitting (for listen-before-talk systems). Embedded CSMA/CA protocol

■Programmable preamble quality indicator (PQI)

■Link quality indication (LQI)

■Whitening and de-whitening of data

■Wireless M-BUS, EN 300 220, FCC CFR47 15 (15.205, 15.209, 15.231, 15.247, 15.249), and ARIB STD T-67, T93, T-108 compliant

■QFN20 4x4 mm RoHS package

■Operating temperature range from -40 °C to 85 °C

Applications

■AMR (automatic meter reading)

■Home and building automation

■WSN (wireless sensors network)

■Industrial monitoring and control

■Wireless fire and security alarm systems

■Point-to-point wireless link

Table 1.	Device summary
Order code		Package	Packing
SPIRIT1QTR		QFN20	Tape and reel

April 2012

Doc ID 022758 Rev 2

1/91

This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to	www.st.com
change without notice.

Contents	SPIRIT1

Contents

1	Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. 5
2	Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. 6
3	Typical application diagram and pin description . . . . . . . . . . . . . . . . .		. 8
	3.1	Typical application diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
4	Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		10
5	Absolute maximum ratings and thermal data . . . . . . . . . . . . . . . . . . .		11
6	Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		12

6.1 General characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.2 Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

6.2.1 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.2.2 Digital SPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 6.2.3 RF receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 6.2.4 RF transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 6.2.5 Crystal oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 6.2.6 Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

7	Operating modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		24
	7.1	Reset sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	27
	7.2	Timer usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	28
	7.3	Low duty cycle reception mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	28
	7.4	CSMA/CA engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	29

8	Block description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		33
	8.1	Power management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	33
	8.2	Power-on-reset (POR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	33
	8.3	Low battery indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	33
	8.4	Voltage reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	33
	8.5	Oscillator and RF synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	33
	8.6	RCO: features and calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	36

2/91	Doc ID 022758 Rev 2

SPIRIT1	Contents

8.6.1 RC oscillator calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

8.7 AFC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 8.8 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 8.9 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 8.10 Temperature sensors (TS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 8.11 AES encryption co-processor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

9	Transmission and reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		40
	9.1	PA configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	40
	9.2	RF channel frequency settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	41
	9.3	RX timeout management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	43
	9.4	Intermediate frequency setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	44
	9.5	Modulation scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	45

9.5.1 Data rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 9.5.2 RX channel bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

9.6 Data coding and integrity check process . . . . . . . . . . . . . . . . . . . . . . . . . 48

9.6.1 FEC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 9.6.2 CRC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 9.6.3 Data whitening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 9.6.4 Data padding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

9.7 Packet handler engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

9.7.1 STack packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 9.7.2 Wireless M-Bus packet (W M-BUS, EN13757-4) . . . . . . . . . . . . . . . . . . 51 9.7.3 Basic packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 9.7.4 Automatic packet filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 9.7.5 Link layer protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

9.8 Data modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 9.9 Data FIFO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 9.10 Receiver quality indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

9.10.1 RSSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 9.10.2 Carrier sense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 9.10.3 LQI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 9.10.4 PQI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 9.10.5 SQI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

9.11 Antenna diversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Doc ID 022758 Rev 2

3/91

Contents			SPIRIT1
	9.12	Frequency hopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . 61
10	MCU interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . 62
	10.1	Serial peripheral interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . 62
	10.2	Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . 64
	10.3	GPIOs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . 65
	10.4	MCU clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . 67
11	Register table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . 69
12	Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . 86
13	Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		. . . 88

4/91	Doc ID 022758 Rev 2

SPIRIT1	List of tables

List of tables

Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table 2. Description of the external components of the typical application diagram . . . . . . . . . . . . . 8 Table 3. Pinout description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Table 4. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 5. Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 6. Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Table 7. General characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Table 8. Power consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 9. Digital SPI input and output (SDO, SDI, SCLK, CSn, and SDN) and GPIO specification

(GPIO_1-4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Table 10. RF receiver characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 11. RF transmitter characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 12. Crystal oscillator characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Table 13. Ultra low power RC oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 14. N-Fractional ÓÄ frequency synthesizer characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 15. Analog temperature sensor characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 16. Battery indicator and low battery detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Table 17. States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Table 18. Commands list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Table 19. POR parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 20. SPIRIT1 timers description and duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 21. Programmability of trans-conductance at startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 22. CP word look-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Table 23. PA_level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Table 24. Frequency threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Table 25. RX timeout stop condition configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Table 26. IF_OFFSET settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Table 27. CHFLT_M and CHFLT_E value for channel filter bandwidth (in kHz, for fclk = 26 MHz) . . 47 Table 28. Packet configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Table 29. MCU clock vs. state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Table 30. Interrupts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Table 31. Digital outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Table 32. Digital inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Table 33. MCU_CK_CONF configuration register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Table 34. MCU clock vs. state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68 Table 35. General configuration registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Table 36. Radio configuration registers (analog blocks). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Table 37. Radio configuration registers (digital blocks) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Table 38. Packet/protocol configuration registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Table 39. Frequently used registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 Table 40. General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 Table 41. QFN20 (4 x 4 mm.) mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 Table 42. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Doc ID 022758 Rev 2

5/91

List of figures	SPIRIT1

List of figures

Figure 1. SPIRIT1 block diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Figure 2. Suggested application diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 3. Diagram and transition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Figure 4. Power-on reset timing and limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Figure 5. LDCR mode timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Figure 6. CSMA flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Figure 7. Shaping of ASK signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Figure 8. Output power ramping configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 9. LFSR block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Figure 10. Threshold of the linear FIFO. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Figure 11. SPI “write” operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 Figure 12. SPI “read” operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Figure 13. SPI “command” operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Figure 14. QFN20 (4 x 4 mm.) dimension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

6/91	Doc ID 022758 Rev 2

SPIRIT1	Description

1 Description

The SPIRIT1 is a very low-power RF transceiver, intended for RF wireless applications in the sub-1 GHz band. It is designed to operate both in the license-free ISM and SRD frequency bands at 169, 315, 433, 868, and 915 MHz, but can also be programmed to operate at other additional frequencies in the 300-348 MHz, 387-470 MHz, and 779-956 MHz bands. The air data rate is programmable from 1 to 500 kbps, and the SPIRIT1 can be used in systems with channel spacing of 12.5/25 kHz, complying with the EN 300 220 standard. It uses a very small number of discrete external components and integrates a configurable baseband modem, which supports data management, modulation, and demodulation. The data management handles the data in the proprietary fully programmable packet format also allows the M-Bus standard compliance format (all performance classes).

However, the SPIRIT1 can perform cyclic redundancy checks on the data as well as FEC encoding/decoding on the packets. The SPIRIT1 provides an optional automatic acknowledgement, retransmission, and timeout protocol engine in order to reduce overall system costs by handling all the high-speed link layer operations.

Moreover, the SPIRIT1 supports an embedded CSMA/CA engine. An AES 128-bit encryption co-processor is available for secure data transfer. The SPIRIT1 fully supports antenna diversity with an integrated antenna switching control algorithm. The SPIRIT1 supports different modulation schemes: 2-FSK, GFSK, OOK, ASK, and MSK. Transmitted/received data bytes are buffered in two different three-level FIFOs (TX FIFO and RX FIFO), accessible via the SPI interface for host processing.

Doc ID 022758 Rev 2

7/91

Introduction	SPIRIT1

2 Introduction

A simplified block diagram of the SPIRIT1 is shown in Figure 1.

Figure 1. SPIRIT1 block diagram

Z /K KEdZK>

Z&/Ed

'W/KͺϬ

dKZh>DK dKZh>DK

'W/K

'W/Kͺϭ

'W/KͺϮ

ZyƉ

&/&KƐdy &/&KƐZy

'W/Kͺϯ

>E

ZyŶ

Zz>>/E<d

^Ŷ

^W/

^ ><

DK^/

D/^K

Ϭ

&Z Y

ϵϬ

^

dy

W

^zEd,

Z '/^d Z^ D W

d DW^ E^

>

<>K>/'/d

> K

EdZ >

K>ŝǀKhd

K>ŝŐŝƚĂů

Z / ^

KZ

ϭsϱ

K>Ks

K>W>>

K>WZK'

K>

sZ '

/ ^

;ĂĐĐ

/'

Z K

/ͬK

^ E

>Žǁ WŽǁĞƌ

ŝŐŝƚĂů> K

yK

ZD

^DW^

KZ

WKZ

;ƌĂǁ

ds

yKhd

y/E

s d

džƚϭ^DW^

džƚϮ^DW^

!-6

The receiver architecture is direct conversion. The received RF signal is amplified by a twostage low-noise amplifier (LNA) and down-converted in quadrature (I and Q) to the intermediate frequency (IF). LNA and IF amplifiers make up the RX front-end (RXFE) and have programmable gain. At IF, I/Q signals are digitized by ADCs. The demodulated data is then provided to an external MCU either through the 96-byte RX FIFO, readable via SPI, or directly using a programmable GPIO pin. A 128-bit AES co-processor is available to perform (offline) data encryption/decryption to secure data transfer.

The transmitter part of the SPIRIT1 is based on direct synthesis of the RF frequency. The power amplifier (PA) input is the LO generated by the RF synthesizer, while the output level can be configured between -30 dBm and +11 dBm in 0.5 dB steps. The data to be transmitted can be provided by an external MCU either through the 96-byte TX FIFO writable via SPI, or directly using a programmable GPIO pin. The SPIRIT1 supports frequency hopping, TX/RX and antenna diversity switch control, extending the link range and improving performance.

The SPIRIT1 has a very efficient power management (PM) system.

8/91	Doc ID 022758 Rev 2

SPIRIT1	Introduction

An integrated switched mode power supply (SMPS) regulator allows operation from a battery voltage ranging from +1.8 V to +3.6 V, and with power conversion efficiency of at least 80%.

A crystal must be connected between XIN and XOUT. It is digitally configurable to operate with different crystals. As an alternative, an external clock signal can be used to feed XIN for proper operation. The SPIRIT1 also has an integrated low-power RC oscillator, generating the 34.7 kHz signal used as a clock for the slowest timeouts (i.e. sleeping and backoff).

A standard 4-pin SPI bus is used to communicate with the external MCU. Four configurable general purpose I/Os are available.

Doc ID 022758 Rev 2

9/91

Typical application diagram and pin description	SPIRIT1

3 Typical application diagram and pin description

3.1Typical application diagram

Figure 2. Suggested application diagram

				1.8V÷3.6V power supply
					C0			C13
INTERFACE		GPIO 1 20	GPIO 2 19	GPIO 3 18	VREG 17			C12
	1 GPIO_0					SDN 15
						L7	L8	C11
	2 MISO					16VBAT
DIGITAL			SPIRIT1			SMPS Ext1 14
	3 MOSI		DIE ATTACH PAD:			SMPS Ext2 13
								L0
	4 SCLK					TX 12
								C15
	5 CSn					GND_PA 11
		6 XOUT	7 XIN	8 VBAT	9 RFp	10 RFn		L1
								C1
						L4
								L2
							L9	C2
					L6	C5
		XTAL
	C9		C10		C6			L3
						C4	C14	C3
					L5
							C7	C8	Antenna
									(50Ω)
									AM09258V1

Table 2. Description of the external components of the typical application diagram

Components	Description
C0	Decoupling capacitor for on-chip voltage regulator to digital part
C1, C2, C3, C14, C15	RF LC filter/matching capacitors
C4, C5	RF balun/matching capacitors
C6, C7, C8	RF balun/matching DC blocking capacitors
C9, C10	Crystal loading capacitors
C11, C12, C13	SMPS LC filter capacitor
L0	RF choke inductor
L1, L2, L3, L9	RF LC filter/matching inductors
L4, L5, L6	RF balun/matching inductors

10/91

Doc ID 022758 Rev 2

SPIRIT1	Typical application diagram and pin description

Table 2. Description of the external components of the typical application diagram (continued)

Components	Description
L7, L8	SMPS LC filter inductor
XTAL	24, 26, 48, 52 MHz

Table 2 assumes to cover all the frequency bands using only four sets of external components.

Doc ID 022758 Rev 2

11/91

Pinout	SPIRIT1

4 Pinout

Table 3.	Pinout description
Pin		Name		I/O	Description
1		GPIO_0		I/O	See description of GPIOs below
2		MISO		O	SPI data output pin
3		MOSI		I	SPI data input pin
4		SCLK		I	SPI clock input pin
5		CSn		I	SPI chip select
6		XOUT		O	Crystal oscillator output. Connect to an external 26 MHz crystal or
					leave floating if driving the XIN pin with an external signal source
					Crystal oscillator input. Connect to an external 26 MHz crystal or to
7		XIN		I	an external source. If using an external clock source with no crystal,
					DC coupling with a nominal 0.2 VDC level is recommended with
					minimum AC amplitude of 400 mVpp
8		VBAT		VDD	+1.8 V to +3.6 V input supply voltage
9		RXp		I	Differential RF input signal for the LNA. See application diagram for a
10		RXn		I	typical matching network
11		GND_PA		GND	Ground for PA
12		TX		O	RF output signal
13		SMPS Ext2		I	Regulated DC-DC voltage input
14		SMPS Ext1		O	DC-DC output pin
					Shutdown input pin. 0-VDD V digital input. SDN should be = ‘0’ in all
15		SDN		I	modes except shutdown mode. When SDN =’1’ the SPIRIT1 is
					completely shut down and the contents of the registers are lost
16		VBAT		VDD	+1.8 V to +3.6 V input supply voltage
17		VREG(1)		VDD	Regulated output voltage. A 100 nF decoupling capacitor is required
18		GPIO3		I/O	General purpose I/O that may be configured through the SPI
					registers to perform various functions, including:
19		GPIO2		I/O
					– MCU clock output
					– FIFO status flags
					– Wake-up input
20		GPIO1		I/O	– Battery level detector
					– TX-RX external switch control
					– Antenna diversity control
					– Temperature sensor output
21		GND		GND	Exposed pad ground pin

1. This pin is intended for use with the SPIRIT1 only. It cannot be used to provide supply voltage to other devices.

12/91

Doc ID 022758 Rev 2

SPIRIT1	Absolute maximum ratings and thermal data

5 Absolute maximum ratings and thermal data

Absolute maximum ratings are those values above which damage to the device may occur. Functional operation under these conditions is not implied. All voltages are referred to GND.

Table 4.	Absolute maximum ratings
	Pin	Parameter	Value	Unit
	8,14,16	Supply voltage and SMPS output	-0.3 to +3.6	V
	17	DC voltage on VREG	-0.3 to +1.4	V
1,3,4,5,15,18,19,20		DC voltage on digital input pins	-0.3 to +3.6	V
	2	DC voltage on digital output pins	-0.3 to +3.6	V
	11	DC voltage on analog pins	-0.3 to +3.6	V
	6,7,9,10	DC voltage on RX/XTAL pins	-0.3 to +1.4	V
	13	DC voltage on SMPS Ext2 pin	-0.3 to +1.4	V
	12	DC voltage on TX pin	-0.3 to +3.6	V
	TSTG	Storage temperature range	-40 to +125	°C
VESD-HBM		Electrostatic discharge voltage	±1.0	KV

Table 5.	Thermal data
Symbol		Parameter			QFN20				Unit
Rthj-amb		Thermal resistance junction-ambient				45			°C/W
Table 6.	Recommended operating conditions
Symbol		Parameter	Min.		Typ.		Max.		Unit
VBAT	Operating battery supply voltage		1.8		3		3.6		V
TA	Operating ambient temperature range		-40				85		°C

Doc ID 022758 Rev 2

13/91

Characteristics	SPIRIT1

6 Characteristics

6.1General characteristics

	Table 7.	General characteristics
	Symbol	Parameter	Min.	Typ.	Max.	Unit
			150		174	MHz
	FREQ	Frequency range	300	-	348	MHz
			387		470	MHz
			779		956	MHz
		Air data rate for each modulation scheme
		Optional Manchester and 3 out of 6 encoding/decoding can be selected
		2-FSK	1		500	kBaud
	DR	GMSK (BT=1, BT=0.5)	1		500	kBaud
		GFSK (BT=1, BT=0.5)	1	-	500	kBaud
		MSK	1		500	kBaud
		OOK/ASK	1		250	kBaud

6.2Electrical specifications

6.2.1Electrical characteristics

Characteristics measured over recommended operating conditions unless otherwise specified. Typical values are referred to TA = 25 °C, VBAT = 3.0 V. All performance is referred to a 50 Ohm antenna connector, via the reference design.

14/91

Doc ID 022758 Rev 2

SPIRIT1							Characteristics
	Table 8.	Power consumption
	Symbol	Parameter		Test conditions	Min.	Typ.		Max.	Unit
				Shutdown (1)		2.5			nA
				Standby (1)		650			nA
				Sleep (1)		950			nA
				Ready (default mode)(1)		400			µA
				Tuning(1)		4.5			mA
				RX (1)		9			mA
	IBAT	Supply current			-			-
				TX (1) +11 dBm 169 MHz		21
				TX (1) +11 dBm 315 MHz		22
				TX (1) +11 dBm 433 MHz		19.5
				TX (1) +11 dBm 868 MHz		21			mA
				TX (1) -8 dBm 169 MHz		6
				TX (1) -8 dBm 315 MHz		6.5
				TX (1) -7 dBm 433 MHz		7
				TX (1) -7 dBm 868 MHz		7

1. See Table 17.

6.2.2Digital SPI

Table 9.	Digital SPI input and output (SDO, SDI, SCLK, CSn, and SDN) and GPIO
	specification (GPIO_1-4)
Symbol	Parameter	Test condition	Min.	Typ.	Max.	Unit
fclk	Clock frequency				10	MHz
CIN	Port I/O capacitance			1.4		pF
		0.1*VDD to 0.9*VDD,
		CL=20 pF (low output		3.5
TRISE	Rise time	current programming)				ns
		0.1*VDD to 0.9*VDD,
		CL=20 pF (high output		2
		current programming)
		0.1*VDD to 0.9*VDD,
		CL=20 pF (low output		5.5
TFALL	Fall time	current programming)				ns
		0.1*VDD to 0.9*VDD,
		CL=20 pF (high output		2.8
		current programming)
VIH	Logic high level input		VDD/2			V
	voltage		+0.3
VIL	Logic low level input				VDD/8	V
	voltage				+0.3

Doc ID 022758 Rev 2

15/91

Characteristics							SPIRIT1
	Table 9.	Digital SPI input and output (SDO, SDI, SCLK, CSn, and SDN) and GPIO
		specification (GPIO_1-4) (continued)
	Symbol	Parameter	Test condition	Min.	Typ.	Max.		Unit
			IOH = -2.4 mA (-4.2 mA if	(5/8)*
			high output current
	VOH	High level output voltage		VDD+				V
			capability is
			programmed).	0.1
			IOL = +2.4 mA (+4 mA if
	VOL	Low level output voltage	high output current			0.5		V
			capability is
			programmed).

6.2.3RF receiver

Characteristics measured over recommended operating conditions unless otherwise

specified. All typical values are referred to TA = 25 °C, VBAT = 3.0 V, no frequency offset in the RX signal. All performance is referred to a 50 Ohm antenna connector, via the reference

design.

Table 10.	RF receiver characteristics
Symbol		Parameter	Test condition	Min.	Typ.	Max.	Unit
			169.4-169.475 MHz, 433-435
RL		Return loss	MHz, 868-868.6 MHz, 310-320			-10	dB
			MHz, 902-928 MHz(1)
CHBW		Receiver channel bandwidth		6		800	kHz
			169MHz 2-FSK 1.2Kbps		-117		dBm
			(4 kHz dev. CH Filter=10kHz)
			169MHz GFSK (BT=0.5)
		Sensitivity, 1% BER (according	2.4Kbps (2.4 kHz dev. CH		-115		dBm
			Filter=7kHz)
		to W-MBUS N mode
			169MHz 2-FSK 38.4Kbps (50
		specification)			-104		dBm
			kHz dev. CH Filter=100 kHz)
RXSENS
			169MHz GFSK (BT=0.5)
			50Kbps (25 kHz dev. CH		-104		dBm
			Filter=100 kHz)
		Sensitivity, 1% PER (packet	315 MHz 2-FSK 1.2 kbps (5.2		-109		dBm
			kHz dev. CH BW=58 kHz)
		length = 20 bytes) FEC
			315 MHz MSK 500 kbps (RX
		DISABLED			-88		dBm
			filter BW=812 kHz)

16/91

Doc ID 022758 Rev 2

SPIRIT1						Characteristics
Table 10.	RF receiver characteristics (continued)
Symbol		Parameter	Test condition	Min.	Typ.		Max.	Unit
			433 MHz 2-FSK 1.2 kbps (1		-117			dBm
			kHz dev. CH BW=6 kHz)
			433 MHz GFSK 1.2 kbps BT=1		-103			dBm
			(5.2 kHz dev. CH BW=58 kHz)
		Sensitivity, 1% PER (packet
			433 MHz GFSK 38.4 kbps
		length = 20 bytes) FEC
		DISABLED	BT=1 (20 kHz dev. CH		-103			dBm
			BW=100 kHz)
			433 MHz GFSK 250 kbps
			BT=1 (127 kHz dev. CH		-92			dBm
			BW=540 kHz)
			868 MHz 2-FSK 1.2 kbps (1		-118			dBm
			kHz dev. CH BW=6 kHz)
			868 MHz GFSK 1.2 kbps BT=1		-109			dBm
			(5.2 kHz dev. CH BW=58 kHz)
		Sensitivity, 1% PER (packet	868 MHz GFSK 38.4 kbps
			BT=1 (20 kHz dev. CH		-106			dBm
		length = 20 bytes) FEC
			BW=100 kHz)
		DISABLED
			868 MHz GFSK 250 kbps
			BT=1 (127 kHz dev. CH		-97			dBm
			BW=540 kHz)
RXSENS
			868 MHz MSK 250 kbps (CH		-95			dBm
			BW=540 kHz)
			915 MHz 2-FSK 1.2 kbps (5.2		-107			dBm
			kHz dev. CH BW=58 kHz)
		Sensitivity, 1% PER (packet	915 MHz 2-FSK 38.4 kbps (20		-105			dBm
			kHz dev. CH BW=100 kHz)
		length = 20 bytes) FEC
			915 MHz 2-FSK 250 kbps (127
		DISABLED			-98			dBm
			kHz dev. CH BW=540 kHz)
			915 MHz MSK 500 kbps (RX		-96			dBm
			filter BW=812 kHz)
			433 MHz OOK 1.2 kbps		-116			dBm
		Sensitivity, 1% PER (packet
			433 MHz OOK 2.4 kbps		-113			dBm
		length = 20 bytes) FEC
			433 MHz OOK 38.4 kbps		-99			dBm
		DISABLED(2)
			433 MHz OOK 250 kbps		-87			dBm
			868 MHz OOK 1.2 kbps		-116			dBm
		Sensitivity, 1% PER (packet
			868 MHz OOK 2.4 kbps		-113			dBm
		length = 20 bytes) FEC
			868 MHz OOK 38.4 kbps		-100			dBm
		DISABLED (2)
			868 MHz OOK 250 kbps		-90			dBm
		Saturation 1% PER (packet
PSAT		length = 20 bytes) FEC	868 MHz GFSK 38.4 kbps		-5			dBm
		DISABLED

Doc ID 022758 Rev 2

17/91

Characteristics						SPIRIT1
Table 10.	RF receiver characteristics (continued)
Symbol		Parameter	Test condition	Min.	Typ.	Max.	Unit
IIP3		Input third order intercept	Input power -50 dBm 915 MHz		-31		dBm
			Desired channel 3 dB above
			sensitivity level. 12.5 kHz		55		dB
			channel spacing, 2-FSK 1.2
			kbps, (RX filter BW=6 kHz)
			Desired channel 3 dB above
			sensitivity level. 100 kHz		47		dB
		Adjacent channel rejection,	channel spacing, 2-FSK 1.2
			kbps, (RX filter BW=58 kHz)
(3)		1% PER (packet length = 20
C/I1-CH		bytes) FEC DISABLED 868	Desired channel 3 dB above
		MHz
			sensitivity level. 200 kHz		36		dB
			channel spacing, GFSK 38
			kbps
			Desired channel 3 dB above
			sensitivity level. 750 kHz		41		dB
			channel spacing, MSK 250
			kbps
			Desired channel 3 dB above
			sensitivity level. 12.5 kHz		57		dB
			channel spacing, 2-FSK 1.2
			kbps, (RX filter BW=6 kHz)
			Desired channel 3 dB above
		Alternate channel rejection,	sensitivity level. 100 kHz		47		dB
			channel spacing, 2-FSK 1.2
(3)		1% PER (packet length = 20	kbps, (RX filter BW=58 kHz)
		bytes)
C/I2-CH			Desired channel 3 dB above
		FEC DISABLED
		868 MHz	sensitivity level. 200 kHz		41		dB
			channel spacing, GFSK 38
			kbps
			Desired channel 3 dB above
			sensitivity level. 750 kHz		56		dB
			channel spacing, MSK 250
			kbps
		Image rejection, 1% PER	868 MHz GFSK 38.4 kbps
			BT=1 (20kHz dev. CH BW=100
(3)		(packet length = 20 bytes) 1%
			kHz), desired channel 3 dB		48		dB
IMREJ		PER (packet length = 20 bytes)
			above the sensitivity limit, with
		FEC DISABLED	IQC correction.
			@ 2 MHz offset, 868 MHz
			GFSK 38.4kbps, desired		-42		dBm
			channel 3 dB above the
		Blocking at offset above the
(4)			sensitivity limit
		upper band edge and below the
RXBLK			@ 10 MHz offset, 868 MHz
		lower band edge 1% BER
			GFSK 38.4kbps, desired		-40		dBm
			channel 3 dB above the
			sensitivity limit.

18/91

Doc ID 022758 Rev 2

SPIRIT1						Characteristics
Table 10.	RF receiver characteristics (continued)
Symbol		Parameter	Test condition	Min.	Typ.		Max.	Unit
			Below 1 GHz		-58			dBm
		Spurious emissions (maximum
			Above 1 GHz up to 4 GHz for
RXSPUR		values according to ETSI EN
			frequency band < 470 MHz, up		-61			dBm
		300 220-1)	to 6 GHz for frequency band >
			470 MHz

1.Guaranteed in an entire single sub band. Reference design can be different for different application bands.

2.In OOK modulation, indicated value represents mean power.

3.Interferer is CW signal (as specified by ETSI EN 300 220 v1).

4.Blocker is CW signal (as specified by ETSI EN 300 220 v1)

6.2.4RF transmitter

Characteristics measured over recommended operating conditions unless otherwise

specified. All typical values are referred to TA = 25 °C, VBAT = 3.0 V. All performance is referred to a 50 Ohm antenna connector, via the reference design.

Table 11.	RF transmitter characteristics
Symbol		Parameter	Test conditions	Min.	Typ.	Max.	Unit
		Maximum output	Delivered to a 50 Ohm single-
PMAX			ended load via reference		11		dBm
		power(1)
			design
			Delivered to a 50 Ohm single-
PMIN		Minimum output power	ended load via reference		-36		dBm
			design
PSTEP		Output power step			0.5		dB

Doc ID 022758 Rev 2

19/91

Characteristics							SPIRIT1
Table 11.	RF transmitter characteristics (continued)
Symbol		Parameter	Test conditions	Min.	Typ.	Max.	Unit
			RF = 170 MHz, frequencies			-36	dBm
			below 1 GHz
			RF = 170 MHz, Frequencies			< -60	dBm
			above 1 GHz
			RF = 170 MHz, frequencies
			within 47-74, 87.5-108,174-			-55	dBm
			230,470-862 MHz
			RF = 434 MHz, frequencies			-42	dBm
			below 1 GHz
		Unwanted emissions
		according to ETSI	RF = 434 MHz, Frequencies			-46	dBm
PSPUR,ETSI		EN300 220-1(harmonic	above 1 GHz
		included, using
			RF = 434 MHz, frequencies
		reference design)
			within 47-74, 87.5-108,174-			-61	dBm
			230,470-862 MHz
			RF = 868 MHz, frequencies			-51	dBm
			below 1 GHz
			RF = 868 MHz, Frequencies			-40	dBm
			above 1 GHz
			RF = 868 MHz, frequencies
			within 47-74, 87.5-108,174-			-54	dBm
			230,470-862 MHz

20/91

Doc ID 022758 Rev 2

SPIRIT1						Characteristics
Table 11.	RF transmitter characteristics (continued)
Symbol		Parameter	Test conditions	Min.	Typ.	Max.	Unit
			RF = 310-320 MHz,
			harmonics (measured with			-37	dBm
			max output power)
			RF = 310-320 MHz, 1.705			<-60	dBm
			MHz <f< 30 MHz
			RF = 310-320 MHz, 30 MHz			<-60	dBm
			<f< 88 MHz
			RF = 310-320 MHz, 88 MHz			<-60	dBm
			<f< 216 MHz
			RF = 310-320 MHz, 216 MHz			<-60	dBm
			<f< 960 MHz
			RF = 310-320 MHz, 960 MHz			<-60	dBm
		Unwanted emissions	<f
PSPUR,FCC		according to FCC part	RF = 902-928 MHz, 1.705
		15(harmonic included,
			MHz <f< 30 MHz (@ max			<-70	dBm
		using reference design)
			output power)
			RF = 902-928 MHz, 30 MHz
			<f< 88 MHz (@ max output			<-70	dBm
			power)
			RF = 902-928 MHz, 88 MHz
			<f< 216 MHz (@ max output			<-70	dBm
			power)
			RF = 902-928 MHz, 216 MHz
			<f< 960 MHz (@ max output			-52	dBm
			power)
			RF = 902-928 MHz, 960 MHz			-41	dBm
			<f (@ max output power)
			2nd and 7th harmonics			-25	dBc

Doc ID 022758 Rev 2

21/91

Characteristics							SPIRIT1
Table 11.	RF transmitter characteristics (continued)
Symbol		Parameter	Test conditions	Min.	Typ.	Max.	Unit
			RF = 312-315 MHz, frequency
			below 1 GHz (@ max output			-41	dBm
			power, according to ARIB
			STD-T93)
			RF = 312-315 MHz, frequency
			above 1 GHz (@ max output			-48	dBm
			power, according to ARIB
			STD-T93)
			RF = 426-470 MHz (@ max
			output power, according to			<-40	dBm
			ARIB STD-T67)
			RF = 920-924 MHz, f< 710
			MHz (@ max output power,			<-55	dBm
			according to ARIB STD-T108)
			RF = 920-924 MHz, 710 MHz
			<f< 915 MHz (@ max output			-55	dBm
			power, according to ARIB
			STD-T108)
			RF = 920-924 MHz, 915 MHz
		Unwanted emissions	<f< 920 MHz (@ max output			-46	dBm
PSPUR,ARIB			power, according to ARIB
		according to ARIB
			STD-T108)
			RF = 920-924 MHz, 920 MHz
			<f< 924 MHz (@ max output			<-60	dBm
			power, according to ARIB
			STD-T108)
			RF = 920-924 MHz, 924 MHz
			<f< 930 MHz (@ max output			-47	dBm
			power, according to ARIB
			STD-T108)
			RF = 920-924 MHz, 930 MHz
			<f< 1000 MHz (@ max output			-55	dBm
			power, according to ARIB
			STD-T108)
			RF = 920-924 MHz, 1000
			MHz <f< 1215 MHz (@ max			<-60	dBm
			output power, according to
			ARIB STD-T108)
			RF = 920-924 MHz, 1215
			MHz <f (@ max output power,			-38	dBm
			according to ARIB STD-T108)

22/91

Doc ID 022758 Rev 2

SPIRIT1						Characteristics
Table 11.	RF transmitter characteristics (continued)
Symbol		Parameter	Test conditions	Min.	Typ.	Max.	Unit
			170 MHz, using reference		46 + j36		Ohm
			design
			315 MHz, using reference		25 + j27		Ohm
			design
		Optimum load	433 MHz, using reference		29 + j19		Ohm
			design
PALOAD
		impedance (simulated
			868 MHz, using reference
		values)			34 - j7		Ohm
			design
			915 MHz, using reference		15 + j28		Ohm
			design
			922 MHz, using reference		42 - j15		Ohm
			design

1. In ASK/OOK modulation, indicated value represents peak power.

6.2.5Crystal oscillator

Characteristics measured over recommended operating conditions unless otherwise specified. All typical values are referred to TA = 25 °C, VBAT = 3.0 V. Frequency synthesizer characteristics are referred to 915 MHz band.

Table 12.	Crystal oscillator characteristics
Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
XTALF	Crystal frequency			26		MHz
FTOL	Frequency tolerance(1)			± 40		ppm
		100 Hz			-90	dBc/Hz
	Minimum requirement on
		1 kHz			-120	dBc/Hz
	external reference phase noise
PNXTAL	mask (Fxo=26 MHz), to avoid	10 kHz			-135	dBc/Hz
	degradation on synthesizer
		100 kHz			-140	dBc/Hz
	phase/noise
		1 MHz			-140	dBc/Hz
TSTART	Startup time(2)	VBAT=1.8 V	100	280	300	µs

1.Including initial tolerance, crystal loading, aging, and temperature dependence. The acceptable crystal tolerance depends on RF frequency and channel spacing/bandwidth.

2.Startup times are crystal dependent. The crystal oscillator transconductance can be tuned to compensate the variation of crystal oscillator series resistance.

Doc ID 022758 Rev 2

23/91

Characteristics										SPIRIT1
Table 13.	Ultra low power RC oscillator
Symbol	Parameter	Test conditions		Min.		Typ.		Max.			Unit
		Calibrated RC oscillator
RCF	Calibrated frequency	frequency is derived from				34.7					kHz
		crystal oscillator frequency.		-
		Digital clock domain 26 MHz
RCTOL	Frequency accuracy after							±1			%
	calibration
Table 14.	N-Fractional ΣΔ frequency synthesizer characteristics
Symbol	Parameter	Test conditions		Min.	Typ.			Max.		Unit
FRES	Frequency resolution			-	100					Hz
		10 kHz		-100	-97			-94		dBc/Hz
		100 kHz		-104	-101			-99		dBc/Hz
PNSYNTH	RF carrier phase noise	200 kHz		-105	-102			-100		dBc/Hz
	(915 MHz band)	500 kHz		-112	-110			-107		dBc/Hz
		1 MHz		-120	-118			-116		dBc/Hz
		2 MHz		-123	-121			-119		dBc/Hz
TOTIME	PLL turn-on/hop time				60			80		µs
SETTIME	PLL RX/TX settling time	Settling time from RX to TX			8.5					µs
		and from TX to RX
CALTIME	PLL calibration time				54					µs

6.2.6Sensors

Characteristics measured over recommended operating conditions unless otherwise specified. All typical values are referred to TA = 25 °C, VBAT = 3.0 V.

Table 15.	Analog temperature sensor characteristics(1)
Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
TERR	Error in temperature	Across all the temperature range		±2.5		°C
TSLOPE	Temperature coefficient			2.5		mV/
						°C
VTS-OUT	Output voltage level			0.92		V
		Buffered output (low output		600		µA
		impedance, about 400 Ohm)
TICC	Current consumption
		Not buffered output (high output		10		µA
		impedance, about 100 kΩ)

1.The temperature readout is a trigger based function. Some processing time is allowed. So, start of conversion trigger -> end of conversion status + read out register.

24/91

Doc ID 022758 Rev 2

SPIRIT1	Characteristics

Table 16. Battery indicator and low battery detector(1)

Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
VBLT	Battery level thresholds		2.1		2.7	V
		Measured in slow battery
		variation (static) conditions		1.535		V
VBOT	Brownout threshold	(inaccurate)
		Measured in slow battery
		variation (static) conditions		1.684		V
		(accurate)
BOThyst	Brownout threshold hysteresis			70		mV

1.For battery powered equipment, the TX does not transmit at a wrong frequency under low battery voltage conditions. It either remains on channel or stops transmitting. The latter can of course be realized by using a lock detect and/or by switching off the PA under control of the battery monitor. For testing reasons this control is enabled/disabled by SPI.

Doc ID 022758 Rev 2

25/91

Operating modes	SPIRIT1

7 Operating modes

The SPIRIT1 is provided with a built-in main controller which controls the switching between the two main operating modes: transmit (TX) and receive (RX).

In shutdown condition (the SPIRIT1 can be switched on/off with the external pin SDN, all other functions/registers/commands are available through the SPI interface and GPIOs), no internal supply is generated (in order to have minimum battery leakage), and hence, all stored data and configurations are lost. From shutdown, the SPIRIT1 can be switched on from the SDN pin and goes into READY state, which is the default, where the reference signal from XO is available.

From READY state, the SPIRIT1 can be moved to LOCK state to generate the high precision LO signal and/or TX or RX modes. Switching from RX to TX and vice versa can happen only by passing through the LOCK state. This operation is normally managed by radio control with a single user command (TX or RX). At the end of the operations above, the SPIRIT1 can return to its default state (READY) and can then be put into a sleeping condition (SLEEP state), having very low power consumption. If no timeout is required, the SPIRIT1 can be moved from READY to STANDBY state, which has the lowest possible current consumption while retaining FIFO, status and configuration registers. To manage the transitions towards and between these operating modes, the controller works as a statemachine, whose state switching is driven by SPI commands. See Figure 3 for state diagram and transition time between states.

Figure 3. Diagram and transition

3(54$/7.

34!.$"9

2%!$9

3,%%0

,/#+

28 48

!-6

The SPIRIT1 radio control has three stable states (READY, STANDBY, LOCK) which may be defined stable, and they are accessed by the specific commands (respectively READY,

26/91

Doc ID 022758 Rev 2

SPIRIT1	Operating modes

STANDBY, and LOCKRX/LOCKTX), which can be left only if any other command is used. All other states are transient, which means that, in a typical configuration, the controller remains in those states, at most for any timeout timer duration. Also the READY and LOCK states behave as transients when they are not directly accessed with the specific commands (for example, when LOCK is temporarily used before reaching the TX or RX states).

	Table 17.	States
	State/mode		Digital LDO	SPI	Xtal	RF Synth.	Wake-up	Response time to
							timer	TX	RX
	SHUTDOWN		OFF (register	Off	Off	Off	Off	NA	NA
			contents lost)
			ON (FIFO and
	STANDBY		register	On	Off	Off	Off	320 µs	320 µs
			contents
			retained)
	SLEEP			On	Off	Off	On	350 µs	350 µs
	READY (Default)			On	On	Off	Don’t care	110 µs	110 µs
	LOCK			On	On	On	Don’t care	NA	NA
	RX			On	On	On	Don’t care	20 µs	NA
	TX			On	On	On	Don’t care	NA	20 µs
	Note:	Response time SHUTDOWN to READY is ~1 ms.

READY state is the default state after the power-on reset event. In the steady condition, the XO is settled and usable as the time reference for RCO calibration, for frequency synthesis, and as the system clock for the digital circuits.

The TX and RX modes can be activated directly by the MCU using the TX and RX commands, or automatically if the state machine wakes up from SLEEP mode and some previous TX or RX is pending.

In LOCK state the synthesizer is in a locking condition(a). If LOCK state is reached using either one of the two specific commands (LOCKTX or LOCKRX), the state machine remains in LOCK state and waits for the next command. This feature can be used by the MCU to perform preliminary calibrations, as the MCU can read the calibration word in the RCO_VCO_CALIBR_OUT register and store it in a non-volatile memory, and after that it requires a further tuning cycle.

When TX is activated by the TX command, the state machine goes into TX state and remains there until the current packet is fully transmitted or, in the case of direct mode TX, TXFIFO underflow condition is reached or the SABORT command is applied.

a.LOCK state is reached when one of the following events occurs first: lock detector assertion or locking timeout expiration.

Doc ID 022758 Rev 2

27/91

Operating modes	SPIRIT1

After TX completion, the possible destinations are:

●TX, if the persistent-TX option is enabled in the PROTOCOL configuration registers

●PROTOCOL, if some protocol option (e.g. automatic re-transmission) is enabled

●READY, if TX is completed and no protocol option is in progress.

Similarly, when RX is activated by the RX command, the state machine goes into RX state and remains there until the packet is successfully received or the RX timeout expires. In case of direct mode RX, the RX stops when the RXFIFO overflow condition is reached or the SABORT command is applied. After RX completion, the possible destinations are:

●RX, if the persistent-RX option is enabled in the PROTOCOL configuration registers

●PROTOCOL, if some protocol option (e.g. automatic acknowledgement) is enabled

●READY, if RX is completed and the LDCR mode is not active

●SLEEP, if RX is completed and the LDCR mode is active.

The SABORT command can always be used in TX or RX state to break any deadlock condition and the subsequent destination depends on SPIRIT1 programming according to the description above.

Commands are used in the SPIRIT1 to change the operating mode, to enable/disable functions, and so on. A command is sent on the SPI interface and may be followed by any other SPI access without pulling CSn high.

The complete list of commands is reported in Table 18. Note that the command code is the second byte to be sent on the MOSI pin (the first byte must be 0x80).

	Table 18.	Commands list
	Command	Command name	Execution state	Description
	code
	0x60	TX	READY	Start to transmit
	0x61	RX	READY	Start to receive
	0x62	READY	STANDBY, SLEEP,	Go to READY
			LOCK
	0x63	STANDBY	READY	Go to STANDBY
	0x64	SLEEP	READY	Go to SLEEP
	0x65	LOCKRX	READY	Go to LOCK state by using the RX configuration of the
				synthesizer
	0x66	LOCKTX	READY	Go to LOCK state by using the TX configuration of the
				synthesizer
	0x67	SABORT	TX, RX	Exit from TX or RX states and go to READY state
	0x68	LDC_RELOAD	All	Reload the LDC timer with the value stored in the
				LDC_PRESCALER/COUNTER registers
	0x69	SEQUENCE_UPDA	All	Reload the packet sequence counter with the value
		TE		stored in the PROTOCOL[2] register.
	0x6A	AES Enc	All	Start the encryption routine
	0x6B	AES Key	All	Start the procedure to compute the key for decryption
	0x6C	AES Dec	All	Start decryption using the current key

28/91

Doc ID 022758 Rev 2