CAT3616 Datasheet, PDF (9/14 Pages) Catalyst Semiconductor – 6-Channel Charge Pump LED Driver with EZDimTM

BLOCK DIAGRAM
CAT3616
Figure 2. CAT3616 Functional Block Diagram
BASIC OPERATION
At power-up, the CAT3616 starts operating in 1x
mode where the output will be approximately equal to
the input supply voltage (less any internal voltage
losses). If the output voltage is sufficient to regulate all
LED currents the device remains in 1x operating
mode.
If the input voltage is insufficient or falls to a level
where the regulated currents cannot be maintained,
the device automatically switches (after 400µs) into
1.5x mode.
In 1.5x mode, the output is approximately equal to 1.5
times the input supply voltage (less any internal
voltage losses).
The above sequence is repeated each and every time
the chip is powered-up or is taken out of shutdown
mode (via EN pin).
© 2006 Catalyst Semiconductor, Inc.
9
Characteristics subject to change without notice
Doc. No. 5018 Rev. A