ST公司的ST7570是S-FSK動力線網(wǎng)絡(luò)系統(tǒng)級芯片(SoC),包括高性能PHY處理器核和協(xié)議控制器核,以及模擬前端(AFE)和線路驅(qū)動器,50Hz時的可編程比特率高達(dá)2.4kbps,1Hz步長的可編載波高達(dá)148.5 kHz,8-18V功率放大器電源,3.3V或5V數(shù)字I/O電源,是符合IEC61334-5-1 S-FSK標(biāo)準(zhǔn)的性價比最好的單片動力線通信解決方案.本文介紹了ST7570主要特性,方框圖以及電路圖,材料清單和PCB布局圖.

The ST7570 is a powerful power line networking system-on-chip. It combines a high-performance PHY processor core and a protocol controller core with a fully integrated analog front end (AFE) and line driver.

The ST7570 features allow the most costeffective, single-chip power line communication solution based on IEC61334-5-1 S-FSK standard. Realized using a multi-power technology with state-of-the-art VLSI CMOS lithography, the ST7570 is based on dual digital core architecture (a PHY processor engine and a protocol controller core) to guarantee outstanding communication performance with a high level of flexibility and programmability.

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 1Arms output current, makes the ST7570 the first complete system-on-chip for power line communication.

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

ST7570主要特性:

■ Fully integrated narrow-band power line networking system-on-chip

■ High performing PHY processor with embedded turn-key firmware for spread frequency shift keying (S-FSK) modulation:

– Programmable bit rate up to 2.4 Kbps (@ 50 Hz)

– 1 Hz step programmable carriers up to 148.5 kHz

– Signal to noise ratio estimation

– Received signal strength indication

■ Protocol engine embedding:

– IEC61334-5-1 PHY and MAC layers

– Alarm management

■ On chip peripherals:

– Host controller UART interface

■ Fully integrated analog front end:

– ADC and DAC

PGA with automatic gain control for high receiving sensitivity

– High linearity modulated signal generation

■ Fully integrated single-ended power amplifier for line driving

– Up to 1 A rms, 14 V p-p output

– Configurable Active filtering topology

Very high linearity

Embedded temperature sensor

– Current control feature

■ 8 to 18 V power amplifier supply

■ 3.3 V or 5 V digital I/O supply

■ Integrated 5 V and 1.8 V linear regulators for AFE and digital core supply

■ Mains zero crossing synchronization

■ Suitable for EN50065 and FCC part 15 compliant applications

■ VFQFPN48 package with exposed pad

■ -40 ℃ to +85 ℃ temperature range

圖1. ST7570方框圖

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 . 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.

圖2. ST7570演示板外形圖

圖3. ST7570演示板各部分分割圖

圖4. ST7570演示板電路圖:ST7570電路圖(1)

圖5. ST7570演示板電路圖:電源部分

圖6. ST7570演示板電路圖:UART接口部分