Its a gr8 ic that includes itself from the pwm brightness controll cktry to the scanner ckt.
The ic minimizes the requrement of the decoder ckt and the counter for the led lighting
dispaly that is explained earlier in my blog.Also there is a internal PWM generator with
several registers for the controll of the whole ic .The register format is given below
We can write the corresponding data in to this registers to controll various operations .
For example if we have to contoll the brightness of the led array use some data between x0to xf.
the pwm is done in odd steps from dutycycle 1/32 to 31/32 hence a total of 16 brightness steps are possible.
The whole array can be divided into 2 namely seg(+)(8)lines and digit(-)(8)lines intersecting at the required points where we place the led or the intersection point is the led junction.
Led driver maximum current can be fixed by the external resistance Rset !<10kohm,
for more information abt the project clickhere