LED Drivers allow for independent channel PWM dimming.
Press Release Summary:
Available with 6.5-28 V input-voltage range, Models MAX16824/MAX16825 feature three 36 V rated, open-drain, constant-current sink outputs capable of delivering up to 150 mA to 3 separate strings of high brightness LEDs. Model MAX16824 provides 3 PWM dimming inputs, while Model MAX16825 features 3-bit transparent latch, 3-bit shift register, and 2 Mbps 4-wire serial interface. ICs provide additional +5 V regulated output with 4 mA output current capability.
Original Press Release:
High-Voltage, 3-Channel, High-Brightness LED Drivers Allow Independent Channel PWM Dimming and LED Current Adjustment
o The MAX16824/MAX16825 are high-voltage, 3-channel, high-brightness LED drivers capable of delivering up to 150mA to three separate strings of HB LEDs.
o These devices allow independent LED current adjustment of the three output channels by providing independent LED current sense for each channel.
o To implement independent LED brightness adjustment, the MAX16824 provides three PWM dimming inputs, while the MAX16825 features a 4-wire serial interface that allows a microcontroller to control the PWM of the output channels.
o Independent control of each channel makes these LED drivers ideal for RGB and single-color applications such as indoor/outdoor LED video displays, architectural and decorative lighting, automotive interior lighting, and LCD backlighting.
SUNNYVALE, CA-December 12, 2007-Maxim Integrated Products (Pink Sheets: MXIM) introduces the MAX16824/MAX16825 3-channel, high-brightness LED (HB LED) drivers with a 6.5V to 28V input-voltage range. These devices feature three 36V-rated, open-drain, constant-current sink outputs capable of delivering up to 150mA to three separate strings of HB LEDs. For optimal design flexibility, these ICs allow independent LED current setting of each channel. To implement this functionality, the MAX16824 provides three PWM dimming inputs to independently control the brightness of each string of LEDs and switch each string on or off. Conversely, the MAX16825 features a 3-bit transparent latch, a 3-bit shift register, and a 2Mbps, 4-wire serial interface. The serial interface allows all output channels to be controlled through an external microcontroller; it also enables multiple MAX16825 drivers to be cascaded and operated together. These flexible LED drivers are ideal for a wide range of applications including industrial, architectural, and decorative lighting; indoor/outdoor LED video displays; automotive interior lighting; and LCD backlighting.
The MAX16824/MAX16825 integrate a pass element with a low dropout voltage, thus eliminating the need for an external power transistor. Providing ±5% accuracy LED current control, each of the three pass elements ensures excellent brightness matching while reducing the size, complexity, and cost of the total driver solution.
The MAX16824/MAX16825 provide an additional +5V regulated output with 4mA output current capability and thermal shutdown in the event of overheating. Both devices are available in a thermally enhanced, 4mm x 4mm, 16-pin TSSOP package with exposed pad. Prices start at $0.91 (1000-up, FOB USA).
