Performance comparison of current mainstream LED dedicated chips
Currently, the main manufacturers of LED display dedicated driver chips are TOSHIBA (Toshiba), TI (Texas Instruments), SONY (Sony), MBI (Polymer Technology), SITI (Dincrystal Technology), etc. In the domestic LED display industry, the chips of these companies are all used.
TOSHIBA products have a high cost performance and the highest market share in the domestic market. The main products are TB62705, TB62706, TB62725, TB62726, TB62718, TB62719, TB62727, etc. Among them, TB62705 and TB62725 are 8-bit source chips, and TB62706 and TB62726 are 16-bit source chips.
TB62725 and TB62726 are upgraded chips of TB62705 and TB62706 respectively. These products have improvements in current output error (including inter-bit and inter-chip error), data shift clock, power supply voltage and chip power consumption.
As mid-range chips, TB62725 and TB62726 have gradually replaced TB62705 and TB62706.
In addition, TB62726 also has a narrow package TB62726AFNA chip, which is only 6.3mm wide (TB62706 SMD package chip width is 8.2mm). This narrow package is more suitable for display screens with smaller dot pitch.
It should be noted that the pin definition of AFNA package is different from that of ordinary package (rotated 90 degrees counterclockwise). TB62718 and TB62719 are driver chips launched by TOSHIBA for the high-end market.
In addition to the functions of ordinary constant current source chips, they also add 256-level grayscale generation mechanism (8-bit PWM), internal current regulation, temperature overheating protection (TSD) and output open circuit detection (LOD) and other functions.
This type of chip is suitable for high-end LED Full-color display screen, of course, its price is not cheap. TB62727 is a new product of TOSHIBA. It mainly adds current regulation, temperature alarm and output open circuit detection functions based on TB62726. Its market positioning is between TB62719 (718) and TB62726. It is planned to be mass-produced in October 2003.
As a world-class IC manufacturer, TI's product performance is naturally beyond doubt.
However, due to the poor development of the Chinese LED market in the early stage, the market share is not high. The main products are TLC5921, TLC5930 and TLC5911. TLC5921 is a high-precision 16-bit source driver chip with TSD and LOD functions. Its inter-bit current error is only ±4%, but its price has always been high until recently it has dropped to the same level as TB72726.
TLC5930 is a 1024-level grayscale (10-bit PWM) 12-bit source chip with 64-level adjustable brightness. TLC5911 is a driver chip positioned in the high-end market.
It is a 16-bit source chip with 1024-level grayscale, 64-level adjustable brightness, TSD, LOD and other functions. There is a metal heat sink under the TLC5921 and TLC5930 chips.
In actual application, please pay attention to avoid the LED lamp pins, otherwise the LED lamp will dim due to leakage.
SONY products have always been positioned in the high-end market, and LED driver chips are no exception. The main products are CXA3281N and CXR3596R.
CXA3281N is an 8-bit source chip with 4096-level grayscale mechanism (12-bit PWM), 256-level brightness adjustment, 1024-level output current adjustment, TSD, LOD and LSD (output short circuit detection) and other functions.
CXA3281N is mainly designed for static drive mode, and its maximum output current is only 40mA.
CXA3596R is a 16-bit source chip, which inherits all the features of CXA3281N in terms of function, mainly improving the output current (from 40mA to 80mA) and the number of constant current source output channels (from 8 to 16).
At present, the price of CXA3281N is more than 1 US dollar, and the price of CXA3596R is more than 2 US dollars.
MBI (Machinery) products basically correspond to TOSHIBA's mid-range products, and the pins and functions are fully compatible. Except for the slightly different external setting resistance of the constant current source, they can basically be directly replaced.
The price of this product is 10~20% lower than that of TOSHIBA, and it is a good choice for mid-range display screens.
MBI's MBl5001 and MBl5016 correspond to TB62705 and TB62706 respectively, and MBl5168 and MBl5026 correspond to TB62725 and TB62726 respectively. In addition, there are new products with LOD function, MBl5169 (8-bit source), MBl5027 (16-bit source), MBl5170 (8-bit source) and MBl5028 (16-bit source).
The chip with LOD and brightness adjustment function adopts MBI's Share-I-OTM technology, and its chip pins are completely compatible with chips without these functions, such as MBl5168 and MBl5026.
In this way, it can be upgraded to new functions without changing the design of the driver board.
SITI (Point Crystal Technology) is a Taiwan company specializing in the research and development and production of LED The company that produces driver chips has stable product performance.
The positioning of Dianjing Technology is similar to that of TOSHIBA, and the performance and price of its products are also comparable. However, the pins are not compatible.
Dianjing's products mainly include ST2221A, ST2221C, DMl34, DMl35, DMl36, DMl33 and ST2226A. Except for ST2221A which is an 8-bit source, the rest are 16-bit source chips.
DMl34, DMl35 and DMl36 are upgraded products of ST2221C. The difference between these three chips is only the output current. The output current of DMl34 is 40-90mA, the output current of DMl35 is 10-50mA, and the output current of DMl36 is 3-15mA.
DMl33 has 64 levels of adjustable brightness, LOD and TSD functions. ST2226A has a 1024-level grayscale mechanism (10-bit PWM) and is a high-end chip.