Wearable (Watch) Solutions Technical Wizard

[TOC]

1. Suggestions on the use of series chips in wearable products

In the Goodix Bluetooth LE chip series, GR551x, GR5525 and GR5526 have strong computing power, data bandwidth and rich peripherals, which are suitable for wearable products such as smart watches; according to the differences of specific resources of these chips, their wearable markets are also different. Users can choose the appropriate chip model to design and develop according to the market positioning of the product.

1.1 GR551x Series

1.1.1 Key performance parameters

• Arm® Cortex®-M4F 32-bit CPU @ 64 MHz

• Bluetooth LE 5.1

  • Data rate: 1 Mbps/2 Mbps, Long Range 500 kbps/125 kbps

  • Sensitivity: – 97 dBm in 1 Mbps mode, – 93 dBm in 2 Mbps mode

  • TX current：3.05 mA @0 dBm，1 Mbps

  • RX current：3.9 mA @1 Mbps

• Supply voltage: 1.7 V to 3.8 V

• I/O voltage: 1.8 V to 3.3 V

• Peripherals: QSPI, SPI, I2S, I2C, UART, ADC, PWM, Calendar Timer, ISO7816

• Security: AES, HMAC, PKC, TRNG

• Package: QFN56, BGA68, BGA55, QFN40

1.1.2 Material number

1.2 GR5526 Series

1.2.1 Key performance parameters

• Arm® Cortex®-M4F 32-bit CPU @ 96 MHz

• Bluetooth LE 5.3

  • Data rate: 1 Mbps/2 Mbps, Long Range 500 kbps/125 kbps

  • Sensitivity: – 98 dBm in 1 Mbps mode, – 94 dBm in 2 Mbps mode

  • TX current: 4.0 mA @ 0 dBm, 1 Mbps

  • RX Current: 3.5 mA @ 1 Mbps

1.2.2 Material number

1.3 GR5525 Series

1.3.1 Key performance parameters

• Arm® Cortex®-M4F 32-bit CPU @ 96 MHz

• Bluetooth LE 5.3

  • AoA/AoD

  • Data rate: 1 Mbps/2 Mbps, Long Range 500 kbps/125 kbps

  • Sensitivity: – 97 dBm in 1 Mbps mode, – 93 dBm in 2 Mbps mode, 101 dBm in LR 500 kbps mode, – 103 dBm in LR 125 kbps mode

  • TX power: – 20 dBm ~ + 7 dBm

  • TX Current: 6.5 mA @ 0 dBm, 1 Mbps, 64 MHz

  • RX Current: 5.4 mA @ 1 Mbps, 64 MHz

• Peripherals: QSPI, SPI, DSPI, I2S, I2C, UART, DMA, ADC, PDM, PWM, Timer, GPIO

• Security: AES, HMAC, PKC, TRNG

1.3.2 Material number

1.4 Selection reference

1.4.1 Parameter comparison

SoC	GR551x	GR5525	GR5526
CPU	Cortex®-M4F 32-bit @ 64 MHz	Cortex®-M4F 32-bit @ 96 MHz	Cortex®-M4F 32-bit @ 96 MHz
X-Flash	Built-in support for 1 MB	Built-in support for 1 MB	Built-in support for 1 MB
	Support external expansion	Support external expansion	Not Support external expansion
D-Flash	QSPI Flash. No MMAP	QSPI Flash. Support MMAP.	QSPI Flash. Support MMAP.
SRAM	256 KB or 128 KB	256 KB	512 KB SRAM + 64 MB PSRAM
PMU	• Supply voltage: 1.7 V~3.8 V	• Programmable thresholds for brownout detection (BOD)	• Programmable thresholds for brown out detection (BOD)
	• Brown out detection	• Supply voltage: 1.9 V to 3.8 V	• Supply voltage: 2.4 V to 4.35 V
	• I/O voltage: 1.8 V to 3.6 V	• I/O voltage: 1.8 V to 3.6 V	• I/O voltage: 1.8 V to 3.6 V
RF	TX power: –20 dBm to +7 dBm	TX power: –20 dBm to +7 dBm	TX power: –20 dBm to +7 dBm
	Sensitivity: –97 dBm @ 1 Mbps	Sensitivity: –97dBm @ 1 Mbps	Sensitivity: –97 dBm @ 1 Mbps
Bluetooth LE	Bluetooth LE 5.1	Bluetooth LE 5.3	Bluetooth LE 5.3
Peripherals
	1 x SPI Master @ 32 MHz	1 x SPI Master @ 48 MHz	1 x SPI Master @ 48 MHz
	1 x SPI Slave	1 x SPI Slave	1 x SPI Slave
	2 x QSPI @ 32 MHz	3 x QSPI @ 48 MHz. Support MMAP.	3 x QSPI @ 48 MHz. Support MMAP.
	1 x I2S Master	1 x I2S Master	1 x I2S Master
	1 x DMA	2 x DMA @ 6ch	2 x DMA @ 6ch
	1 x I2S Slave	1 x I2S Slave	1 x I2S Slave
	2 x I2C	4 x I2C @ 3.4 MHz	6 x I2C @ 3.4 MHz
	2 x UART	4 x UART	6 x UART
	13-bit ADC	13-bit ADC	13-bit ADC
	6ch x PWM	6ch x PWM	6ch x PWM
	4 x Hardware Timers	4 x Hardware Timers	4 x Hardware Timers
	1 x AON Hardware Timer	1 x AON Hardware Timer	1 x AON Hardware Timer
	2 x WDT	1 x AON WDT	1 x AON WDT
	1 x RTC	2 x RTC	2 x RTC
	x	1 x DSPI	1 x DSPI
	x	x	1 x OSPI (64 MB OSPI DDR PSRAM)
	x	x	1 x GPU
	x	x	1 x DC
	x	x	1 x USB 2.0 FS
	x	1 x PDM	1 x PDM
	I/O @ 39 max.	I/O @ 50 max.	I/O @ 50 max.

1.4.2 GR5525 vs GR551x

Description of main upgrades of GR5525 relative to GR551x at the bandwidth level:

1. The system frequency is increased from 64 MHz to 96 MHz.

2. The QSPI maximum frequency is increased from 32 MHz to 48 MHz, and the bus architecture is increased from APB to AHB, increasing the bus access speed.

3. QSPI adds MMAP access mode to support direct bus addressing of NOR Flash and QSPI PSRAM.

4. The QSPI FIFO depth is increased from 8 to 16/32, and the DMA FIFO is also increased from 8 to 32, which improves the transfer efficiency of DMA.

5. The number of QSPIs is increased to 3, the number of DMAs is increased to 2, and more QSPI interface peripherals can be expanded as needed.

Based on the above upgrade, the access throughput, access efficiency and access friendliness have been greatly improved.

1.4.3 GR5526 vs GR5525

Compared with the GR5525, the GR5526 adds a more powerful Graphics module (2.5D GPU + Display Controller + 64 MB OSPI PSRAM), USB and PDM modules, and an SRAM space of 512 KB. It can design wearable products with more cool effect and higher resolution.

1.4.4 General reference for type selection

SoC	Explain
GR551x	Resolution range generally recommended is < = 320 X 320
GR5525	As an upgraded version of 551x, it supports software design with larger resolution and easier use. At present, the resolution of mass production can reach up to 454 X 454, without tearing and stuttering.
GR5526	Both frame rate and effect can be considered. Better UX interactive experience can be designed based on 2.5D GPU. The frame rate can also be very high. The software is easy to use and simple to develop. It is recommended to choose medium and high resolution watches.

2. Reference to the scheme

Index	Reference	Get the connection
OS Usage	GR5xx FreeRTOS Manual	GR5xx FreeRTOS Sample Manual
LVGL Framework	LVGL Official Doc	https://docs.lvgl.io/
GPU principle（Not Necessary）	GR5526 GPU User Guide	GR5526 GPU Developer's Guide
Optimizqation for Display	GR5526 Display Guide	GR5526刷屏指南
DFU & OTA	GR5xx OTA Guide	GR5xx Firmware Upgrade Development Guide
Lower power	GR5526 power mode and measurment	GR5526 Power Mode and Power Measurement Description