LM3560 Datasheet, PDF (18/42 Pages) Texas Instruments – LM3560 Synchronous Boost Flash Driver w/ Dual 1A High-Side Current Sources (2A Total Flash Current)

INTERRUPT OUTPUT (INT MODE)
The TX2/INT/GPIO2 pin can be reconfigured as an active low
interrupt output by setting bit [6] in the GPIO Register to ‘1’
and configuring TX2/INT/GPIO2 as a GPIO2 output (bits [4:3]
of GPIO Register = 11). In this mode, TX2/INT/GPIO2 will pull
low when any of these conditions exist.
1. The LM3560 is configured for NTC mode (Configuration
Register 1 bit [4] = 1), and the voltage at LEDI/NTC has
fallen below VTRIP (1V typical).
2. The LM3560 is configured for VIN Monitor mode (VIN
Monitor Register bit [0] = 1), and VIN falls below the
programmed VIN Monitor Threshold.
3. The LM3560 is configured for VIN Flash Monitor mode
(VIN Monitor Register bit [3] = 1), and VIN falls below the
programmed VIN Flash Monitor Threshold.
Once INT is pulled low due to any of the above conditions
having been met, INT will only go high again if any of the con-
ditions are no longer true and the Flags Register is read.
FIGURE 7. TX2 As an Interrupt Output (During an NTC Event)
30113808
INDICATOR LED/THERMISTOR (LED1/NTC)
The LEDI/NTC pin serves a dual function: either as a pro-
grammable LED message indicator driver, or as a comparator
input for negative temperature coefficient (NTC) thermistors.
MESSAGE INDICATOR CURRENT SOURCE (LEDI/NTC)
LEDI/NTC is configured as a message indicator current
source by setting Configuration Register 1 bit [4] = (0) default.
The indicator current source is enabled/disabled via the En-
able Register bit [6] = (1). Bit [7] of the Enable Register
enables the Message Indicator in blink mode. If the message
indicator is set for blinking mode, the pattern programmed into
the Indicator Register, and Indicator Blinking Register is out-
put on the Indicator current source.
The Indicator Blinking Register controls the following (see
Table 6 ):
1. Number of blank periods (BLANK #). This has 16
settings. t_BLANK = t_ACTIVE × BLANK# , where t_ACTIVE =
t_PERIOD × PERIOD#
2. Pulse width (t_PULSE) has 16 settings between 0 and 480
ms in steps of 32 ms. The pulse width is the duration that
the indicator current is at its programmed set point at the
end of the ramp-up time.
The Indicator Register controls the following (see Table 5 ):
1. Indicator current level (I_IND). There are 8 indicator current
levels from 2.25 mA to 18 mA in steps of 2.25 mA.
2. Number of periods (PERIOD #). This has 8 steps. A
period (t_PERIOD) is found by (t_PERIOD = t_R + t_F + 2 x
t_PULSE). (see Figure 8 for indicator timing).
3. Ramp times (t_R or t_F) for turn-on and turn-off of the
indicator current source. Four programmable times of 78
ms, 156 ms, 312 ms, and 624 ms are available. The ramp
times apply for both ramp-up and ramp-down and are not
independently changeable.
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