MAX1573 white led driver electronic project schematic


Posted on Feb 5, 2014

This white led driver circuit circuit drives as many as four white LEDs in parallel from a 3. 3V source, and adjusts the total LED current from 1mA to 106mA, in 64 steps of 1dB each. To control the LED brightness, op amp U2 monitors the difference between the high-side voltage and the wiper voltage of digital potentiometer U1. The op amp then mult


MAX1573 white led driver electronic project schematic
Click here to download the full size of the above Circuit.

iplies that voltage by a gain to set the maximum output current. Zero resistance at the pot`s W1 terminal corresponds to minimum LED current, and therefore minimum brightness. Because the SET voltage is fixed (at 0. 6V), any voltage change at the left side of R5 changes ISET, and the resulting change in LED currents changes their brightness level. R5 sets the maximum LED current: R5 = 215x0. 6/ILED(Desired) (ILED is the current through one LED). U1 integrated circuit is a digital potentiometer with logarithmic taper and an analog-voltage wiper for which each tap corresponds to 1dB of attenuation between H1 and W1 (pins 11 and 9).




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Human detector circuit
Mobile voltage regulator
Programming the XMEGA with an ISP
Amp Circlotron
Heat Sensitive Switch
60 watt bass amplifier



Top