The LM3492HC/-Q1 device integrates a
boost converter and a two-channel current regulator to implement a highly efficient and cost
effective LED driver. This device drives two individually dimmable LED strings with a maximum power
of 15 W and an output voltage of up to 65 V. The boost converter employs a proprietary
projected-on-time control method to give a fast transient response with no compensation required.
The nearly constant switching frequency can be set to a level from 200 kHz to 1 MHz. Ceramic
capacitors stabilize the application circuit and produce no audible noise on dimming. The
programmable peak current limit and soft-start features reduce current surges at start-up. An
integrated, 190-mΩ, 3.9-A, N-Channel MOSFET switch minimizes the solution size. The fast slew rate
current regulator allows high frequency and narrow pulse width dimming signals to achieve a very
high contrast ratio of 10000:1. The LED current can be set from 50 mA to 250 mA by a single
For all available packages, see the orderable addendum at the
end of the data sheet.
All trademarks are the property of their respective owners.
To maximize the efficiency,
(DHC) automatically adjusts the output voltage to a minimum. The DHC also facilitates a single BOM
for different number of LED in a string, which is required for back-light panels of different size,
thereby reducing overall development time and cost. The LM3492HC device
includes a COMM pin that serves as a bidirectional I/O pin. The versatile COMM pin interface with
an external micro-controller unit (MCU) is used for the following functions: power-good,
overtemperature, IOUT overvoltage and undervoltage indications, switching frequency tuning, and
channel 1 disabling. Other supervisory functions of the device include precise enable, VCC
undervoltage lockout, current regulator over-power protection, and thermal shutdown protection. The
device is available in the thermally enhanced PWP, 20-pin package.
View datasheet View product folder