Datasheet
Pin settings LED7707
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2.2 Pin description
Table 2. Pin functions
N° Pin Function
1COMP
Error amplifier output. A simple RC series between this pin and ground is
needed to compensate the loop of the boost regulator.
2RILIM
Output generators current limit setting. The output current of the rows can be
programmed connecting a resistor to SGND.
3 BILIM
Boost converter current limit setting. The internal MOSFET current limit can
be programmed connecting a resistor to SGND.
4FSW
Switching frequency selection and external sync input. A resistor to SGND is
used to set the desired switching frequency. The pin can also be used as
external synchronization input. See
Section 5.1.5 on page 14 for details.
5MODE
Current generators fault management selector. It allows to detect and manage
LEDs failures. See
Section 5.3.2 on page 22 for details.
6 AVCC + 5 V analog supply. Connect to LDO5 through a simple RC filter.
7LDO5
+ 5 V LDO output and power section supply. Bypass to SGND with a
1 µF ceramic capacitor.
8 VIN Input voltage. Connect to the main supply rail.
9SLOPE
Slope compensation setting. A resistor between the output of the boost
converter and this pin is needed to avoid sub-harmonic instability.
Refer to
Section 6.1 on page 25 for details.
10 SGND
Signal ground. Supply return for the analog circuitry and the current
generators.
11 ROW1 Row driver output #1.
12 ROW2 Row driver output #2.
13 ROW3 Row driver output #3.
14 ROW4 Row driver output #4.
15 ROW5 Row driver output #5.
16 ROW6 Row driver output #6.
17 PGND Power ground. Source of the internal power MOSFET.
18 OVSEL
Over-voltage selection. Used to set the desired 0 V threshold by an external
divider. See
Section 5.1.4 on page 14 for details.
19 LX Switching node. Drain of the internal power MOSFET.
20 DIM Dimming input. Used to externally set the brightness by using a PWM signal.
21 EN
Enable input. When low, the device is turned off. If tied high or left open, the
device is turned on and a soft-start sequence takes place.
22 FAULT
Fault signal output. Open drain output. The pin goes low when a fault condition
is detected (see Section 5.3.1 on page 22 for details).
23 SYNC Synchronization output. Used as external synchronization output.
24 SS Soft-start. Connect a capacitor to SGND to set the desired soft-start duration.