The MAX25530 evaluation kit (EV kit) demonstrates
the MAX25530 IC, which is a highly integrated power
supply plus LED backlight driver for automotive TFT-LCD
applications. The EV kit is a fully assembled and tested
surface-mount PCB that provides a complete power-management
solution for automotive displays. The EV
kit demonstrates one buck-boost converter, one boost
converter, two gate-voltage controllers, and a boost
converter that powers a quad-string LED driver.
The EV kit can be configured to operate in a stand-alone
mode or in an I2C mode.
The TFT bias section of the EV kit operates from a 2.8V to
5.5V DC supply voltage. The step-up switching regulator
(POS) is configured for a 5V to 18V output that provides
up to 120mA. The inverting buck-boost converter (NEG)
generates a negative output that tracks the positive output
(down to a minimum of -7V) and provides up to 100mA.
The gate-driver power supplies consist of regulated
charge pumps that generate +28V (DGVDD) and -21.5V
(DGVEE) and can deliver up to 10mA each, depending
on the POS setting. Operation at 430kHz and 2.2MHz is
possible.
The LED driver section demonstrates a step-up DC-DC
pre-regulator followed by four channels of linear current
sinks. The step-up pre-regulator switches at 2.2MHz
or 440kHz and operates as a current-mode controlled
regulator capable of providing up to 600mA for the current
sinks. Each channel can operate up to 48V and provides
up to 150mA.
The LED driver portion of the EV kit operates from a DC
supply voltage of 4.5V up to the High-Brightness (HB)
LED string-forward voltage. The EV kit can withstand a
52V load-dump condition. The EV kit also demonstrates
the IC’s features, such as adaptive voltage optimization,
Overvoltage and Undervoltage protection, cycle-by-cycle
current limit, thermal shutdown, and digital PWM dimming
operation using a digital PWM input signal to control the
brightness of the HB LEDs.
The EV kit provides an I2C interface that can operate in
conjunction with the MINIQUSB+ adapter board or a third-party
I2C master. The EV kit also includes Windows®-compatible software that provides a simple graphical user
interface (GUI) for exercising the features of the IC.
Applications
- Automotive Central Information Displays
- Automotive Dashboards
- Automotive Head Up Displays
- Automotive Navigation System