GD32 as STM32 Alternative? – Is it safe?

You might think it is a yes-and-no answer because, to an extent, the GD32 is an stm32 equivalent. 

In short, yes, it’s safe, but we wouldn’t recommend it for every use; please read on.

Let me give you a bit of context; we’re amid a massive STM32 shortage, which is why clones like the GD32 have become more popular among engineers. 

And companies doing crazy things, like, hoarding washing machines. 

In a recent LinkedIn post called ” Washing machines are the new toilet paper,” our CEO talks about a recent report from ASML that mentions that a major manufacturing conglomerate is buying up washing machines to salvage the MCUs because of the global shortage.

Here in Titoma, after plenty of tests, we’re manufacturing a first 3K run of devices using GD32.

The performance is generally similar, and moving from STM32 to GD32 is relatively easy as the GD32 is pin to pin compatible.

But; let’s go deep into the comparison between one and the other

In addition, you’ll find the different applications of these ultra low-power MCUs. 

This way, you are sure that you are using the right board for your project.

Table of Contents

WHAT ARE GD32 AND STM32?

The GD32 is a simple 32-bit microchip from a developer company in China – GigaDevices. 

It’s a universal microcontroller running on 32-bit ARM cortex architecture.

This affordable and ultra-low-power development board line gives new degrees of support for MCU applications. 

As a result, it has become a rival for STM32. 

GD32 Microchip

On the other hand, STM32 originates from a French-Italian company, STMicroelectronics. It is also a family of quality flash microcontrollers built on a 32-bit ARM Cortex processor core. 

STM32 is the original model upon which the GD32 was built. 

IS GD32 A SUITABLE REPLACEMENT FOR STM32?

The STM32 shortage allowed products like the GD32 and others to surface. 

Most of them came with ARM Cortex-M processors and FPU with single-precision data processing and a USB interface. 

However, the GD32 is one high-performance ARM cortex microcomputer built on a similar interface as the ST.

Therefore, there are many ways the two Nucleo development boards are alike. 

The Nucleo evaluation boards both support ease of development, digital signal processing, and full integration. 

Nonetheless, the STM32 is ideal for several large and small projects alike. 

It uses an industry-standard core with a vast choice of tools and software resources. 

STM32 Microchip

On the other hand, the GD32 is different from the STM32 in terms of its details and specifications. 

Due to this, the GD32 is not entirely an excellent STM32 replacement in all projects.

WHAT’S THE DIFFERENCE BETWEEN GD32 AND STM32

The Kernel

The two boards both run on a high-performance ARM Cortex-M processor core. 

However, the STM32 resources run on the first-generation 32-bit ARM cortex version, while the GD32 uses the second-generation model of the ARM M3 core.

Internal oscillator main frequency

The high-speed external clock (HSE)

The HSE of GD32 has a main frequency of 108MHz. Meanwhile, the STM32 high-speed external clock is a bit lower at 72MHz. In addition, some variants come with floating-point instructions.

High-speed internal clock (HSI)

The HSI of the GD32 has a main frequency of 108MHz. In contrast to that, the STM32 has a main frequency of 64MHz.

Power supply

External power supply

The GD32 board’s external power supply ranges from 2.6V to 3.6V. The STM32 board, however, has a supply range from 2V to 3.6V.

Core voltage

The core voltage is also not the same for the two single-chip microcomputers. The GD32 core voltage is less than the STM32. The STM32 uses a core voltage of 1.8V. While on the other hand, the GD32 core voltage is 1.2V.

Flash differences

Flash execution speed

During program execution, these board chips work differently. Typically, the GD32 flash memory has zero (0) wait cycles.

However, the flash execution speed of the STM32 varies :

  • 0<SYSCLK<24MHz = 0 waiting period.
  • 24MHz<SYSCLK≤48MHz = 1 waiting period.
  • 48MHz<SYSCLK≤72MHz = 2 waiting periods.

Flash erasing time

Generally, the flash erasing time for GD takes longer. The typical value of the GD32 page erasing is 100ms. The actual value, though, is approximately 60ms. But, the corresponding ST models have a typical value between 20 to 40ms.

Power consumption

Typically, the GD has a low power consumption compared to the STM32. However, the GD32 gives very high performance, a longer GD standby mode, sleep mode, and shutdown mode. 

Its other features combine real-time capabilities if you use the same operation settings.

Serial port

During operation, the GD32 sends data in a continuous pattern. But in between any two bytes of packet data sent, there is an idle Bit. 

We wouldn’t use it on medical devices

It uses only two stop-bit modes, such as 1/2. This pattern is different in the STM32 microchip, which supports four stop-bit patterns: 0.5/1/1.5/2. 

Generally, the different UART builds of the GD32 and STM32 are not significant for communication. You have access to a longer communication time, however, in GD.

ADC difference

Also, there is a difference in their Analog-Digital Conversion sampling clock ratios. 

By comparison, the GD’s sampling time and input impedance are lower; its 14MHz ADC sampling clock runs at a main frequency of 72MHz.

FSMC

In the GD32, there is an FSMC interface for 100pin and above. 

In comparison, the STM32 has an FSMC for high-performance support for various peripherals. 

Usually, the 100pin must be 256K or above. Other firmware libraries that support the STM32 FSMC interface include SRAM, USB, LCD modules, NAND flash, etc.

FLASH and RAM size difference in 103 series

To a large extent, the 303 and 103 models are the same. But they differ in terms of flash sizes and RAM. For example, the GD103 has a larger flash and RAM size than the 303 counterparts. 

In the same way, it is also larger than the ST103.

The Leadtime

Gigadevice gives a 20-week lead time for their GD32 products. The STM32 lead time of up to 52 weeks, which is why GD32 is becoming sort of famous now.

Anti-interference ability

The STM32’s microcontroller pins communicate using SPI normally. But this is not the case with the GD32. 

This condition is because there are dual IICC copper cables behind the PCB board. These peripherals affect the signals generated. 

In contrast, the STM waveform is better. A possible reason is that the STM32 pins have filtering circuits, unlike the GD32. 

In all, the anti-interference ability of the STM32 is better than the GD32.

IS IT SAFE TO USE GD32 AS AN ALTERNATIVE FOR STM32?

Being so similar yet different, the answer is YES. The GD32 is the best-suited alternative for the STM32. 

It is an ST32 alternative; it is among the most effective development tools available. 

Like the STM32, it has a hardware abstraction layer for MCU users of Raspberry Pi or Arduino IDE. Hence, it is probably the most popular STM32 clone around.

APPLICATION OF GD32 AND STM32

GigaDevice in the production of the GD32 made sure to give STM32 some real competition. So, you’ll find it fit for many applications, such as:

  • Motor drives.
  • User interface.
  • Industrial control.
  • Power monitors.
  • Alarm systems, etc.

Meanwhile, STM32 is fit for all of the above and 

  • Audio ICs.
  • Comparators and amplifiers.
  • Automotive logic circuits.
  • Automotive MCUs.
  • Timers and clocks, etc.
  • Medical

STM32F CHIP COMPATIBILITY

The STM32F is one of the other chips based on the STM32. Its code is compatible with the Arduino board and other software. 

You should encounter no problems using this 32-bit ARM board as the features are very similar.

CONCLUSION

In summary, the GD32 and the STM32 are not fully interchangeable. 

Both MCUs have similar features but differ on some things. One of which is the relatively larger flash memory and RAM size of the GD32. 

Also, the kernel size, port configuration, and programming code patterns are different. However, in some cases, the GD32 performs as well as its counterpart, the STM32.