lp5522tmx National Semiconductor Corporation, lp5522tmx Datasheet - Page 10

• Manufacturer Part Number: lp5522tmx
• Description: Programmable Led Driver
• Manufacturer: National Semiconductor Corporation

TRAINING END COMMAND
Blinking sequence programming ends once Training End command is introduced. Three rising edges within time period of t
EN-
is interpreted as Training End command. Note that blank period is also reguired after Training End command. During blanc
TER
period no rising edges are allowed.
When Training End command is introduced during LED OFF time capturing, LED OFF time is recorded and chip goes to standby
mode.
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If Training End command is introduced during LED ON time capturing, the associated LED ON period is not recorded and hence
neither OFF time. Notice that valid OFF time before Training End is longer than half of Minimum LED OFF period (T_CYCLE_L).
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LED TIMEOUT ON/OFF TIMES
When LP5522 is in training mode and CTRL signal is high longer than LED Timeout ON time, the ON time counter saturates. In
this case saturated ON time is recorded and LED OFF time capturing is started. At the same time LED is switched off even if the
CTRL signal is still high.
If ON time counter has saturated, LED OFF time recording is terminated either by giving a Train End command or setting the CTRL
signal to low and back to high. Setting the CTRL signal back to high records the LED OFF time and starts next ON time capturing.
If anyhow CTRL is still high after the LED Timeout OFF time has been elapsed the OFF time counter saturates and saturated OFF
time is recorded. After that chip waits the CTRL signal to go low which cause the chip to go Standby.
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