Maxim introduced programmable 4 series high brightness (HB) LED driver MAX16826

For white light, RGB and RGB plus amber LED. The device is designed to realize the green lighting technology in automotive applications, which greatly improves the flexibility of the system and provides the lowest cost backlight driver.

MAX16826 integrates a switching regulator controller, 4 channel linear current source driver, one way ADC and I2C interface. The I2C interface allows the dynamic regulation of the output voltage to achieve maximum efficiency; it also allows the manufacturer to set the current of each series of LED to accommodate the inherent differences in the LED, thereby reducing manufacturing costs.

MAX16826 has a high degree of configurability and excellent performance, is the ideal choice for automotive information terminal display backlight, automotive dashboard, industrial and desktop monitors and LCD tv. The device is also suitable for use in front lamps and near / high beam lamps, as well as semiconductor lighting (SSL).

Advanced programming capabilities greatly reduce the cost of the program, improve the conversion efficiency of MAX16826 designed specifically for automotive applications, can provide cost-effective scalable OEM program. The advanced programmable function of the device makes it possible to replace a small number of components for a wide variety of designs, in addition to the system manufacturer's ability to adapt to the inherent differences in the LED, thereby reducing the overall cost of production.

MAX16826 uses an innovative architecture that allows the dynamic setting of the output voltage of the regulator and the magnitude of the LED current per channel. Internal ADC measure the drain voltage of the drive transistor for each series of HB LED. Measurement results can be transmitted to the external microcontroller through the I2C interface to optimize the output voltage and LED fault monitoring.

Dynamic programmability allows the same drive circuit to be applied to multiple projects, during which the LED current or voltage is simply regulated via the I2C interface. The function does not need to replace the components, greatly simplifying the production. In addition, the output voltage can be optimized by reducing the voltage drop on the linear driver, thereby improving the conversion efficiency, thereby reducing the power consumption and heating of the display.

Existing design uses integrated MOSFET to achieve LED current regulation. MAX16826 is different from this, the switching regulator and the LED current regulator are all external MOSFET. This unique way allows the device to drive more HB LED on each string, each LED string can flow through a greater current, so that designers can use MAX16826 in a number of projects. At the same time, the heat management is enhanced because the heat is distributed through more devices and larger circuit boards.

Integrated fault monitoring function to reduce the number of external devices MAX16826 able to detect and respond to LED open circuit and short circuit fault. When the fault condition is detected, the IC triggers the internal circuit and closes the fault unit quickly. The integrated fault monitoring is able to protect the HB LED drive and the automotive electrical system from being damaged. In addition, the automotive electrical system can read the fault state through the I2C interface of the device, and make the corresponding response. MAX16826 advanced features to meet the high reliability requirements of automotive systems, to minimize the number of components, reduce program costs.

Other advantages of the HB LED driver for increased flexibility, the switching regulator can be configured as a boost or SEPIC converter, so the LED voltage can be higher or lower than the input voltage of the power supply. MAX16826 also provides programmable switching frequency (100kHz to 1MHz), which can reduce the electromagnetic interference (EMI) in noise sensitive applications such as automotive displays. In addition, each suction current driver has a direct PWM input, independent control of each channel LED brightness. The designer can independently adjust the LED brightness of each color in the RGB application, so as to get the best color control. Other features include cycle by cycle current limiting, output over voltage protection and over temperature protection.

MAX16826 designed for harsh working conditions, operating at -40 degrees C to +125 degrees C automotive temperature range. The device can withstand up to 40V of the load transient, and can work in cold start. MAX16826 provides enhanced heat dissipation in the 5mm x 5mm, 32 pin TQFN package. Chip starts at $2.05 (1000 chips, us FOB).