概觀
The IS31LT3505 is a constant current step-up
converter with internal NMOS. The step-up converter
topology allows series connection of the white LEDs
so the LED currents are identical for uniform
brightness as well as constant output voltage to drive
other devices. The output current of each channel
can be set by an external resistor and dimming the
brightness of LEDs with the PWM signal or DC
voltage. The IS31LT3505 operates with a switching
frequency up to 1MHz. A low 0.3V feedback voltage
minimizes power loss in the current setting resistor
for better efficiency. With OVP circuit, the chip and
the system can be safe even if the load is not
connected.
IS31LT3505 is available in MSOP-10. It operates
from 6V to 30V over the temperature range of -40°C
to +85°C.