DM163 ETC2 [List of Unclassifed Manufacturers], DM163 Datasheet - Page 15

• Manufacturer Part Number: DM163
• Description: 8x3-CHANNEL CONSTANT CURRENT LED DRIVER
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

Particular Phenomenon
waveform demonstrate a very different characteristics compare to conventional PWM counter.
(1) Nonconsecutive counter
similar to Figure 7. Its waveform is spread-out into each PWM cycle, resulting lots of intermediate
pulses during each PWM cycle. In Fig 7, if all the intermediate pulses are added up, it would
equal to 50% luminance which is the same as the conventional method. By spreading out the
PWM pulses, this approach can help prevent LED from flickering in lower grayscale situation.
(2) 8+6 bits Comparator
comparator’s output will be “H” only when value at “+” is larger then the value at “-“ (in other
word, comparator will be “L” when value in“+” equals to value in “-“ or value in “+” is less than
value in “-“). Only when both 8 bit and 6 bit comparator are “H” will there be current in the output
channel.
two certain scenario. In the first case, DM163 output will always be “OFF” when either one of the 8
bit or 6 bit bank is filled with 0. In 2
loaded “H”, DM163 output will exhibit its highest luminance value (but not 100% luminance value).
Due to the nature of comparators design, PWM control signal will be zero in the condition of 8bits
counter=8’bFF or 6bits counter=6’b3F. Consequently, the PWM control signal will be 0 for
2
8
+2
DM163 incorporates a different PWM counter, as described in Figure 2, hence its output
The non-consecutive PWM counter incorporate by DM163 demonstrated a waveform pattern
8x3-CHANNEL CONSTANT CURRENT LED DRIVERS
6
+1 GCK rather than always high.
The comparator illustrated in Fig 2 is another one of the unique designs in DM163. The
Due to this unique comparator design, DM163 exhibit a very distinct output characters in
點晶科技股份有限公司
SILICON TOUCH TECHNOLOGY INC.
Figure 7. An Example of Nonconsecutive PWM Signal
nd
scenario, when all bit value at both 8 bit and 6 bit bank are
Version: A.004
DM163
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