Datasheet

LM3463
www.ti.com SNVS807A –MAY 2012–REVISED MAY 2013
PIN DESCRIPTIONS (continued)
Pin Name Description Application information
The function of this pin differs depending on the selected operation mode
Multi-function input pin.
that sets by the MODE pin.
Direct PWM mode: Apply a bi-level PWM signal (TTL logic high and low)
Channel 0/1 PWM dimming control to this pin to enable/disable ch0 and ch1. Apply logic high to this pin to
7 DIM01
enable channel 0 and 1.
Serial data input In serial interface mode, this pin is configured as the serial data input.
In DC interface mode, the voltage on this pin is converted into PWM
DC voltage dimming control
dimming duty for channel 0 and 1.
The function of this pin differs depending on the selected operation mode
Multi-function input pin.
that sets by the MODE pin.
Direct PWM mode: apply bi-level PWM signal (TTL logic high and low) to
Channel 2/3 PWM dimming control this pin to enable/disable ch2 and ch3. Apply a logic high to this pin to
enable both channel 2 and 3.
8 DIM23
In serial interface mode, this pin is configured as the serial clock signal
Serial clock input
input.
In DC interface mode, the voltage on this pin is converted into PWM
DC voltage dimming control
dimming duty for channel 2 and 3.
The function of this pin differs depending on the selected operation mode
Multi-function input pin.
that sets by the MODE pin.
Direct PWM mode: apply bi-level PWM signal to this pin to enable/disable
Channel 4 dimming control
channel 4. Apply logic high to this pin to enable channel 4.
In serial interface mode, this pin is configured as load pulse input, pulling
9 DIM4
this pin low will latch the shifted-in data into internal register of the
Load data control pin LM3463. This pin is pulled low if the requested load operation is not
completed. User should check the status of this pin before writing data into
the LM3463 through this pin.
In DC interface mode, the voltage on this pin is converted into PWM
DC voltage dimming control
dimming duty for channel 4.
The function of this pin differs depending on the selected operation mode
Multi-function input pin.
that sets by the MODE pin.
Direct PWM mode: Apply a bi-level PWM signal (TTL logic high and low)
Channel 5 dimming control to this pin to enable/disable channel 5. Apply a logic high to this pin to
10 DIM5
enable channel 5.
Serial operation mode This pin should connect to GND when serial operation mode is selected.
In DC interface mode, the voltage on this pin is converted into PWM
DC voltage dimming control
dimming duty for channel 5.
Serial control signal output pin for cascade operation. This signal
Serial data output for cascade
synchronizes with the rising edge of the CLKOUT signal and carries
operation
information to the slave devices to turn on LEDs.
11 SYNC
Sync. pulse input in direct PWM This is a synchronization signal input pin for the slave device to perform
mode LED pretest upon system startup.
Dimming clock output for cascade Dimming clock output for cascade operation. The frequency at this pin
12 CLKOUT operation / Sync pulse output for equal to 1/2 of the internal clock or externally applied clock frequency.
Direct PWM mode
Connect a resistor from this pin to GND to set the additional bias current
13 ISR Start up current control pin
to the C
DHC
upon system startup.
The voltage on this pin defines the threshold of the drain voltage of the
external MOSFETs (V
DRn
) to begin output current reduction.
As the V
DRn
exceeds V
DRVLIM
, the LED driving current reduces according
14 DRVLIM MOSFET power limit setting input
to the increasing of V
DRn
at certain fixed rate. This function prevents the
MOSFET from over-heating. The maximum power dissipation is limited to
V
DRVLIM
* I
LED
(per ch.).
Dynamic headroom control time Connect a capacitor (C
DHC
) from this pin to ground to program the DHC
15 CDHC
constant capacitor loop response.
Connect a capacitor, C
FLT
from this pin to ground to program the fault de-
16 FCAP Fault de-bounce capacitor
bounce time.
17 GND System ground This pin should connect to the system ground
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