MAX16819/20: 2MHz High-Brightness LED Drivers with High-Side Current Sense and 5000:1 Dimming
The MAX16819/MAX16820, step-down constant-current high-brightness LED (HB LED) drivers provide a costeffective solution for automotive interior/exterior lighting, architectural and ambient lighting, LED bulbs such as MR16 and other LED illumination applications.
The MAX16819/MAX16820 operate from a 4.5V to 28V input voltage range and feature a 5V/10mA on-board regulator. A high-side current-sense resistor adjusts the output current and a dedicated PWM input (DIM) enables a wide range of pulsed dimming.
The MAX16819/MAX16820 are well suited for applications requiring a wide input voltage range. The high-side current-sensing and an integrated current-setting circuitry minimize the number of external components while delivering an LED current with ±5% accuracy. A hysteretic control algorithm ensures excellent input-supply rejection and fast response during load transients and PWM dimming. The MAX16819 features a 30% inductor current ripple and the MAX16820 features a 10% current ripple. These devices operate up to 2MHz switching frequency, thus allowing for small component size.
The MAX16819/MAX16820 operate over the -40°C to +125°C automotive temperature range and are available in 3mm x 3mm x 0.8mm, 6-pin TDFN packages.
- High-Side Current Sense
- Dedicated Dimming Control Input
- 20kHz Maximum Dimming Frequency
- Hysteretic Control: No Compensation
- Up to 2MHz Switching Frequency
- ±5% LED Current Accuracy
- Adjustable Constant LED Current
- 4.5V to 28V Input Voltage Range
- Over 25W Output Power
- 5V, 10mA On-Board Regulator
- -40°C to +125°C Operating Temperature Range
- Architectural, Industrial, and Ambient Lighting
- Automotive RCL, DRL, and Fog Lights
- Heads-Up Display
- Indicators and Emergency Lighting
The MAX16820 evaluation kit (EV kit) demonstrates a step-down, constant-current, hysteretic controlled switching regulator for driving high-brightness LEDs (HB LEDs) using the MAX16820 controller IC. This EV kit is configured to supply an average output LED current of 1A, and operates from a 5V to 28V supply.
- MAX16820 data sheet
- REFERENCE DESIGN 4381 INCLUDES: Tested Circuit Schematic BOM Description Layout MR-16 LED Driver w/5V Auxiliary Output to Power Pulsating LED Cooler
- REFERENCE DESIGN 4382 INCLUDES: Tested Circuit Schematic Description Layout Reference Design for a 5S2P AR111 Lamp LED Driver
- APPLICATION NOTE 4479 Diagnose LEDs by Monitoring the Switch-Mode Duty Cycle
- APPLICATION NOTE 4509 DC Voltage Controls PWM Dimming of High-Brightness LEDs (HB LEDs)