BK7258 240MHz+2x480MHz low-power IoT platform

Description

BK7258 is a low-power IoT chip with Arm-V8 Cortex-M33 integrated with 2.4GHz Wifi6+Bluetooch 5.4. It has 3 CPUs, a running frequency of 240MHz+2x480MHz, and built-in 8M Flash+16M Psram. BK7258 can operate LVGL at 480MHz with a working current of up to 9mA. We have connected a GPS/BDS/GLONASS/Galileo/IRNSS/QZSS module in the L1+L5 band and a SIM7670G 4G module compatible with the global frequency band. We have connected the acceleration/gravity sensor, geomagnetic sensor, air pressure sensor, and temperature/humidity sensor for it. Two QSPI interfaces of BK7258 are connected to a 2.16" 480x480 AMOLED display. One display is used to display GPS maps, and the other displays motion information and others. We designed a 1/5" GC2145 DVP camera FPC for it and installed a 6x6MM lens. A MIC and a horn. A 4.35V rechargeable lithium battery interface, 3D printing shell and strap.

Project Logs

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Preliminary UI elements are designed on the LVGL simulator.
ElecLab • 4 days ago • 0 comments

The resolution of the whole device is 480x960, which is divided into two 480x480 screens. The first control screen is on the left, and the GPS map display screen is on the right. The display and black screen of the second screen can be controlled separately.
Since the simulator uses the code of lvgl 9, and the SDK of BK7258 is based on lvgl 8.x, it needs to be properly modified to port.
BK7258 RGB PCB is back
ElecLab • 4 days ago • 0 comments

PCB uses 4 layers of 1mm thickness and 0.3/0.45mm drilling.
There are two LCD sockets on the PCB, one is 40P SPI+RGB666+TP. There are many types of this small screen with capacitance touch. Generally, the SPI port needs to be used to initialize the LCD screen chip.
The other is an ordinary 40P 4.3" 5" 7" regular TFT screen, which uses a separate 6P TP FPC to connect a capacitive touch screen.
Typical screen sizes and resolutions are listed behind the PCB.
The camera FPC has been welded after using the steel mesh.
ElecLab • 4 days ago • 0 comments

6x2.2uF 0201 capacitors and GC2145 BGA chips are very small and need the help of a magnifying glass.
The lens holder of 6x6MM is indeed very small, which is limited by the resolution and size of 1/5" sensor, and the area that contains 6 capacitors, which is the best configuration.
The new PCB supports RGB interface using BK7258
ElecLab • 04/08/2026 at 08:47 • 0 comments

We used BK7258 to design another PCB that supports RGB+SPI+TP and RGB interface displays, which can support displays of a wide range of sizes and resolutions. This PCB removes the 4G module. We marked the list of supported displays on the back of the PCB.

We chose a 5" 800x480 reflective display as an application with a separate Goodix capacitive touch screen. There is no need to turn on the backlight in the sun, which can save a lot of energy and extend the battery life.

We tested this display on the T113 EVK as shown in the following figure: