ST AN3213 Application note

AN3213

Application note

ST7570 S-FSK power line networking system-on-chip design guide for AMR

Introduction

The ST7570 demonstration board has been realized as a useful tool which exploits the performance capability of the ST7570 S-FSK power line networking system-on-chip (References 1).

With this demonstration board, it is possible to evaluate the ST7570 features and its transmitting and receiving performance directly on the power line.

The coupling interface is designed to allow the ST7570 device to transmit and receive on the mains using a spread-spectrum FSK signal with 63.3 and 74 kHz tone frequencies, within the European CENELEC EN50065-1 standard A-band, specified for automatic meter reading (References 4).

Figure 1. ST7570 demonstration board with outline dimensions

	As can be seen from Figure 1, special effort has been made to make the demonstration
	board as compact as possible, while including all the features which enable the ST7570 to
	perform at its best.
Note:	The information provided in this application note refers to the EVALST7570-1 demonstration
	board.

October 2010

Doc ID 17429 Rev 1

1/64

www.st.com

Contents	AN3213

Contents

1	Abbreviations used in this document . . . . . . . . . . . . . . . . . . . . . . . . . .	. 7
2	Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
3	Safety recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	11
4	ST7570 S-FSK power line networking system-on-chip description . . 12
5	Demonstration tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	13
6	Test and measurement tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	14
7	ST7570 demonstration board description . . . . . . . . . . . . . . . . . . . . . .	15
	7.1 Line coupling section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	26

7.1.1 Transmission active filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 7.1.2 Reception passive filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 7.1.3 Power line coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 7.1.4 Zero crossing coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 7.1.5 Input impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

7.2 Conducted disturbances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.2.1 Conducted emission (CE) measurements . . . . . . . . . . . . . . . . . . . . . . . 35 7.2.2 Noise immunity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 7.2.3 AWGN tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 7.2.4 NBI tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7.3 PCB layout guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

41

7.3.1 Thermal performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 7.3.2 Ground connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 7.3.3 Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

7.4 Thermal impedance and power dissipation calculation . . . . . . . . . . . . . . 43 7.5 Oscillator section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 7.6 Surge and burst protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 7.7 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

8

Application ideas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

50

2/64	Doc ID 17429 Rev 1

AN3213	Contents

8.1 Three-phase architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 8.2 Received signal strength indication (RSSI) . . . . . . . . . . . . . . . . . . . . . . . 51

9	FAQs and troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		54
	9.1	FAQs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	54
	9.2	Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	56

10 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

11 Normative references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Appendix A Board layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Doc ID 17429 Rev 1

3/64

List of tables	AN3213

List of tables

Table 1. Electrical and thermal characteristics of the ST7570 demonstration board . . . . . . . . . . . . . 8 Table 2. TX_OUT level vs. TX_GAIN - typical values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 3. BOM list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Table 4. ST parts on board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Table 5. Line coupling transformer specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Table 6. Noise level SN0 and SN1 during AWGN tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Table 7. Narrow-band interferer immunity test settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Table 8. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

4/64	Doc ID 17429 Rev 1

AN3213	List of figures

List of figures

Figure 1. ST7570 demonstration board with outline dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Figure 2. I(VCC) vs. I(PA_OUT) curve - typical values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Figure 3. ST7570 block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 4. Board drawing with indication of the various sections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Figure 5. Global view of the ST7570 demonstration board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 6. ST7570 schematic circuit (part 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 7. Power supply section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Figure 8. UART interface section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Figure 9. External microcontroller connection section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 10. ST7570 schematic circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 11. Reset circuit section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 12. JTAG lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 13. Current limit setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 14. Non-isolated zero crossing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 15. USB to UART connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 16. Reception and transmission filter schematics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Figure 17. Measured frequency response of the transmission active filter (typical) . . . . . . . . . . . . . . 27 Figure 18. Montecarlo simulation of the transmission active filter frequency response. . . . . . . . . . . . 28 Figure 19. Measured frequency response of the reception passive filter (typical). . . . . . . . . . . . . . . . 29 Figure 20. Montecarlo simulation of the reception passive filter response . . . . . . . . . . . . . . . . . . . . . 30 Figure 21. Measured frequency response of the Tx active + passive filter loaded with the EN50065-1

LISN impedance (typical) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Figure 22. Montecarlo simulation of the transmission line coupling response loaded with the

EN50065-1 LISN impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Figure 23. Non-isolated zero crossing coupling circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Figure 24. ZC_IN_A vs. mains voltage - delay measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Figure 25. ZC_IN_A vs. mains voltage - jitter measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Figure 26. Measured input impedance modulus of the line coupling - reception mode (typical) . . . . . 35 Figure 27. Measured input impedance modulus of the line coupling - transmission mode (typical) . . 35 Figure 28. Conducted emissions test setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Figure 29. Conducted emissions: transmission spectrum, quasi-peak measurement, 3 kHz - 150 kHz,

line-to-earth, as per EN50065-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Figure 30. Conducted emissions: transmission spectrum, quasi-peak measurement, 3 kHz - 150 kHz, neutral-to-earth, as per EN50065-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Figure 31. Conducted emissions: transmission spectrum, quasi-peak measurement, 150 kHz - 30 MHz, line-to-earth, as per EN50065-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Figure 32. Conducted emissions: transmission spectrum, quasi-peak measurement, 150 kHz - 30 MHz, neutral-to-earth, as per EN50065-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Figure 33. Noise immunity test setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Figure 34. Measured BER vs. SNR curve (typical), white noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Figure 35. Example of stencil openings for the QFN48 package. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 36. PCB copper dissipating area on top layer for the ST7570 demonstration board . . . . . . . . 42 Figure 37. PCB copper dissipating area on bottom layer for the ST7570 demonstration board . . . . . 42 Figure 38. Packet-fragmented transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Figure 39. Measured ST7570 thermal impedance curve (typical) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Figure 40. Simulation model of the thermal impedance ZthJA of the ST7570 mounted on the

demonstration board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Figure 41. Carrier frequency deviation vs. crystal tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Doc ID 17429 Rev 1

5/64

List of figures	AN3213

Figure 42. Delay between mains zero crossing and transmission start: jitter vs. crystal tolerance . . . 46 Figure 43. Common mode disturbance protection - positive disturbance . . . . . . . . . . . . . . . . . . . . . . 47 Figure 44. Common mode disturbance protection - negative disturbance. . . . . . . . . . . . . . . . . . . . . . 48 Figure 45. Differential mode disturbances protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Figure 46. Example of power supply EMI input filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Figure 47. Scheme of principle for non-switched three-phase architecture . . . . . . . . . . . . . . . . . . . . . 50 Figure 48. Scheme of principle for switched three-phase architecture . . . . . . . . . . . . . . . . . . . . . . . . 51 Figure 49. SNR0 estimator at 1200 bps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Figure 50. SNR1 estimator at 1200 bps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Figure 51. SNR0 estimator at 2400 bps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Figure 52. SNR1 estimator at 2400 bps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Figure 53. PCB layout - component placing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Figure 54. PCB layout - top view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Figure 55. PCB layout - bottom view . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

6/64	Doc ID 17429 Rev 1

AN3213	Abbreviations used in this document

1Abbreviations used in this document

●AC = alternate current

●AFE = analog front end

●AMR = automated meter reading

●AWGN = additive white gaussian noise

●BER = bit error rate

●BOM = bill of material

●CE = conducted emissions

●DC = direct current

●EMC = electro-magnetic compliance

●EMI = electro-magnetic immunity

●GUI = graphical user interface

●MAC = medium access control layer (as per IEC61334-5-1 protocol stack definition -

References 5)

●NBI = narrow-band interferer

●LISN = line impedance stabilization network

●PA = power amplifier

●PCB = printed circuit board

●PHY = physical layer (as per IEC61334-5-1 protocol stack definition - References 5)

●PLC = power line communication

●PSU = power supply unit

●RBW = resolution bandwidth

●SBW = signal bandwidth

●S-FSK = spread frequency shift keying

●SNR = signal-to-noise ratio

●SSD = start subframe delimiter (as per IEC61334-5-1 physical layer definition -

References 5)

Doc ID 17429 Rev 1

7/64

Electrical characteristics	AN3213

2 Electrical characteristics

Table 1.	Electrical and thermal characteristics of the ST7570 demonstration board
Parameter				Value			Notes
		Min		Typ		Max
				Thermal data
Ambient operating		-40 °C				85 °C
temperature
							Measured on the
ST7570 thermal						50 °C/W ((1))	ST7570 demonstration
							board 2-side PCB with
resistance
							thermal pad and 4x4
							thermal via array
				Transceiver section
		Transmitting specifications (Tx mode)
Transmitted signal				63.3 kHz
Tone “1” frequency
Transmitted signal				74 kHz
Tone “0” frequency
Transmitted signal				19 kHz			2400 BAUD
-20 dB bandwidth
Transmitted output				1 A rms			R15 = 130 Ω
current limit
		Receiving specifications (Rx mode)
Minimum detectable				46 dBµV rms			1200 BAUD, BER<10-3,
received signal							SNR > 20 dB
Reception filter -3 dB				50 kHz
bandwidth
			Mains coupling specifications
Transformer isolation		4 kV ((2))
			Power supply requirements
AC mains voltage range		85 V AC				265 V AC
Mains frequency				50-60 Hz
VCC power supply		8 V		13 V		18 V
voltage
VCC power supply
current absorption – RX				12 mA			DL1 on (7 mA typ.)
	mode

8/64	Doc ID 17429 Rev 1

AN3213					Electrical characteristics
Table 1.	Electrical and thermal characteristics of the ST7570 demonstration board (continued)
Parameter			Value			Notes
VCC power supply						VCC = 8 to 18 V,
current absorption – TX		20 mA		500 mA		I(PA_OUT) = 0 to 1 A
	mode					rms
VDDIO digital supply		-10 %	3.3 V	+10 %
voltage
						DL2 on (5 mA typ.),
VDDIO digital supply			40 mA			no external
current absorption						microcontroller
						connection through J1
Maximum required
power (typical			7 W			VCC = 13 V
application)

1.Measured over a continuous transmission period of 3000 seconds (steady-state thermal dissipation).

2.Note that STMicroelectronics does not guarantee transformer isolation. STMicroelectronics assumes no responsibility for the consequences that may arise from that risk.

Table 2.	TX_OUT level vs. TX_GAIN - typical values
	TX_GAIN		TX_OUT
		[dBµV rms]		[V rms]
	31	123		1.420
	30	122		1.265
	29	121		1.128
	28	120		1.005
	27	119		0.896
	26	118		0.798
	25	117		0.712
	24	116		0.634
	23	115		0.565
	22	114		0.504
	21	113		0.449
	20	112		0.400
	19	111		0.357
	18	110		0.318
	17	109		0.283
	16	108		0.252
	15	107		0.225
	14	106		0.201

Doc ID 17429 Rev 1

9/64

Electrical characteristics					AN3213
	Table 2.	TX_OUT level vs. TX_GAIN - typical values (continued)
		TX_GAIN	TX_OUT
		13	105		0.179
		12	104		0.159
		11	103		0.142
		10	102		0.127
		9	101		0.113
		8	100		0.101
		7	99		0.090
		6	98		0.080
		5	97		0.071
		4	96		0.063
		3	95		0.057
		2	94		0.050
		1	93		0.045

Figure 2. I(VCC) vs. I(PA_OUT) curve - typical values

, 9&& >P$@

, 3$B287 >P$@

!-V

10/64

Doc ID 17429 Rev 1

AN3213	Safety recommendations

3 Safety recommendations

The board must be used by expert technicians only. Due to the high voltage (85-265 VAC) present on the non-isolated parts, special care must be taken in order to avoid electrical risks regarding user safety.

There is no protection against accidental human contact with high voltages.

After disconnecting the board from the mains, no live parts must be touched immediately because of the energized capacitors.

It is mandatory to use a mains insulation transformer to perform any tests on the high voltage sections, using test instruments such as, spectrum analyzers or oscilloscopes.

Do not connect any probe to high voltage sections if the board is not isolated from the mains supply, in order to avoid damaging instruments and demo tools.

Warning: STMicroelectronics assumes no responsibility for the consequences arising from any improper use of this development tool.

Doc ID 17429 Rev 1

11/64

ST7570 S-FSK power line networking system-on-chip description	AN3213

4ST7570 S-FSK power line networking system-on-chip description

The ST7570 is a powerful power line networking system-on-chip, combining a highperforming PHY processor core and a protocol controller core with a fully integrated analog front end (AFE) and line driver, for a scalable future-proof, cost effective single chip narrowband power line communication solution based on IEC61334-5-1 S-FSK technology (References 5).

The ST7570 comes with a dedicated FW implementing full PHY and MAC protocol layers and services compliant with the open standard IEC 61334-5-1, mainly developed for smart metering applications in EN50065-1 A band, but also usable for other command and control applications and remote load management in B band (References 4).

The on-chip analog front end, featuring analog-to-digital and digital-to-analog conversion and automatic gain control, plus the integrated power amplifier delivering up to 1 A rms output current, makes the ST7570 the first complete system-on-chip for power line communication.

The line coupling network design is also simplified, leading to a very low cost BOM. Safe performance operations are guaranteed while keeping power consumption and distortion levels very low, therefore making ST7570 an ideal platform for the most stringent application requirements and regulatory standard compliance.

For further details, please refer to References 1 and 2.

Figure 3. ST7570 block diagram

	3$B,1	3$B,1	&/
					7KHUPDO
3$B287					0DQDJHPHQW					21 &+,3
	3$	2XWSXW &XUUHQW								0HPRULHV
			&RQWURO
					/LQH 'ULYHU	21 &+,3				:$7&+'2*
						0HPRULHV
7;B287	'$&	*$,1								7,0(56
		&75/		%3)
								3URWRFRO
	7;$)(							&RQWUROOHU
			''6							8$57	7B5(4
					3+< 3URFHVVRU						5;'
											7;'
5;B,1											%5
	3*$	$'&		%3)							%5
	5;$)(
											35(6/27 =& 76 %,7
9&&
9
9'',2	3RZHU 0DQDJHPHQW
9						=HUR &URVVLQJ 'HWHFWLRQ		&ORFN 0DQDJHPHQW
	9&&$			9''		=&B,1B$	=&B,1B'			;287
								9''B3//	;,1
	9
				9				9
											!-V

12/64

Doc ID 17429 Rev 1

AN3213	Demonstration tools

5 Demonstration tools

The minimum set of evaluation tools required to test the ST7570 power line communication is two communication nodes, each made up of the following elements:

●A PC running the ST7570 GUI software tool

●One EVALST7570-1 board

●One ALTAIR04-900 demonstration board as the power supply unit (PSU).

For further details regarding the ST7570 GUI software and the available evaluation tools, please visit http://www.st.com/powerline.

Doc ID 17429 Rev 1

13/64

Test and measurement tools	AN3213

6Test and measurement tools

●Spectrum/network/impedance analyzer

–Agilent 4395A: 10 Hz - 500 MHz

–Agilent 43961A Impedance test kit

●Differential active probe

–Agilent 1141A differential probe: 1 MΩ, 7 pF

●Agilent 1142A probe control and power module:

–DC reject 0.05 Hz

●EMC analyzer

–Agilent E7402A: 100 Hz - 3 GHz

●Two-line V-network (LISN)

–Rohde&Schwarz ENV216

●Isolation transformer

–1000 VA, 0 - 250 V variable output

●Oscilloscope

–Tektronik TDS 754D: 500 MHz, 2 GS/s

●Surge/burst generator

–Volta UCS 500-M

14/64

Doc ID 17429 Rev 1

AN3213	ST7570 demonstration board description

7 ST7570 demonstration board description

The ST7570 demonstration board is made up of the following sections:

●ST7570 supply and digital connections

●Line coupling section, including four subsections:

–Transmission active filter

–Reception passive filter

–Power line coupling

–Zero crossing coupling.

The board has also four external connections:

●AC mains (line and neutral) on CN1 connector

●VCC (8 to 18 V) and VDDIO (3.3 or 5 V) supply voltages on CN2 connector

●USB interface for PC connectivity on CN3 USB type B connector

●Digital interface on J1 7x2 connector, collecting all the signals required to interface an external microcontroller board.

Figure 4. Board drawing with indication of the various sections

$& PDLQV		/LQH FRXSOLQJ
FRQQHFWRU		VHFWLRQ

'LJLWDO ,QWHUIDFH FRQQHFWRU

67 VXSSO\ DQG GLJLWDO

VHFWLRQ

,2''9±&&9QRLFWHQQRF SSO\X6

%86UFWRHQQRF

86% 8$57 LVRODWHG LQWHUIDFH !-V

Figure 5 gives a global view of the demonstration board. Figure 6 shows the ST7570 and the line coupling circuits, while Figure 10 represents the USB to UART connection circuit.

Table 3 lists the components chosen to realize the demonstration board. All the parts have been selected to obtain good performance in a real case application.

The layout of the printed circuit board is given in Appendix A: Board layout - Figure 53,

Figure 54 and Figure 55.

Doc ID 17429 Rev 1

15/64

ST7570 demonstration board description	AN3213
Figure 5. Global view of the ST7570 demonstration board

	&1						&1
	+($'(5 ..						+($'(5 ..
86%	3/0
9'',2	9'',2	9	966	9&&	1		3
7;'	7;'
5;'	5;'
7B5(4	7B5(4
*1'	*1'
86%	3/0
							!-V

Figure 6. ST7570 schematic circuit (part 1)

9'',2

5

5

5

5

5

N

N

N

N

N

5(6(59('

5(6(59('

9'',2

5(6(59('

5(6(59('

5

5(6(59('

73

9''

=&B,1B'

'/

&

/(' 5('

5(6(59(' 9'',2 9'' *1' 5(6(59(' 5(6(59(' 5(6(59(' *1' %5 %5 7B5(4 =&B,1B'

Q)

9'',2

-3

&/26(

5(6(59('

5(6(59('

9''

*1'

5(6(59(' 5(6(59(' 5(6(59(' 5(6(59('

%5

%5

7B5(4

=&B,1B' =& 76 %,7

5

9'',2

73

N

&

=& 76 %,7

7;'

=& 76 %,7

Q)

7;'

5;'

966$

9'',2

5;'

966$

9'',2

9'',2

9'',2

9'',2

75671

*1'

75671

*1'

706

&

706

67

1&

&

*1'

5(6(59('

*1'

5(6(59('

X)

7&.

Q)

7&.

1&

7'2

7'2

1&

7',

9'',2

7',

9'',2

5(6(71

9''B5(*B 9

5(6(71

9''B5(*B 9

9''

3$B287

9''

3$B287

;,1

966

;,1

9''B3//

9&&$ =&B,1B$ 5;B,1 7;B287

3$B,1

966

;287

3$B,1

9''B5(*B 9

9''

*1'

966$

9&&

;,1

&/

(3

966

&

&

<

8

Q)

X)

0+]

)%

5

)%

5

;287

;287 *1' 966$ 9''B3// 9&&$ =&B,1 5;B,1 7;B287 3$B,1 3$B,1 &/ 9&&

966$

73

73

*5281' 3/$1(

9''

)%

9''B3//

%(/2: 7+( '(9,&(

%/0 3* 61

9''

9''B3//

9&&

&

&

&

73

&

&

Q)

X)

9&&$

Q)

966

Q)

X)

966$

9&&$

&

&

73

966$

Q)

X)

966$

966$

!-V

16/64

Doc ID 17429 Rev 1

AN3213						ST7570 demonstration board description
	Figure 7.	Power supply section
		9&&			9&&
					)%	9'',2
		9
					%/0 3* 61
		966

		-3
9&&		&/26(
9
		-3
		&/26(	5
		5
			.
		'/	'/
	/(' <(//2:		/(' *5((1

!-V

Figure 8. UART interface section

!-V

Doc ID 17429 Rev 1

17/64

ST7570 demonstration board description	AN3213

Figure 9. External microcontroller connection section

!-V

18/64

Doc ID 17429 Rev 1

AN3213

.10 Figure

&

ST7570

S)

circuit schematic

&

&

S)

73

S)

$

7$

%

17429 ID Doc

5

3$B,1

5

9&&

9&&$

9&&

N

N

1

&

'

9$& ;

3$B,1

6736 /$

Q)

&

5

3$

&

7 %

/

&

1&

Rev

N

73

3$B287

$

%

3

&

5

5

5

3$B,1

X)

X+

Q) <

3$B,1

'

1

7;B287

'

ST7570

N

N

N

60 7 &$

Q)

6736 /$

5

73

&

5

&

&

1

3$B287

73

1&

N

Q)

S)

7'. (3 :(

7;B287

966$

5;B,1

&

description board demonstration

Q)

/

&

'

73

Q)

X+

60 7 9 &$

5;B,1

966$

19/64

V-!

ST7570 demonstration board description									AN3213
Figure 11. Reset circuit section

!-V

Figure 12. JTAG lines

!-V

20/64

Doc ID 17429 Rev 1