TLC6C5712-Q1 Datasheet, PDF (19/68 Pages) Texas Instruments – 12-Channel, Full-Diagnostic, Constant-Current-Sink LED Driver

www.ti.com
TLC6C5712-Q1
SLVSCO9A – AUGUST 2015 – REVISED AUGUST 2015
7.3.5.6 Weak LED Supply (WLS) Detection
The TLC6C5712-Q1 device provides weak-LED-supply detection to avoid reporting false faults due to supply
failure. Implementation of weak-LED-supply detection is by monitoring the V_(SENSE) voltage using the internal
threshold voltage V_(WLS) as a reference.
The default threshold V_(WLS) is set for a 5-V supply. If a 3.3-V LED supply is needed, the threshold voltage can
be tuned to V_{(WLS_OPT)} by setting the [WLS_TH] bit HIGH.
when a fault is detected, the [WLS_FAULT_FLAG] bit is set if the [WLS_MASK] masking bit is not active. The
[WLS_FAULT_FLAG] bit remains latched even if the voltage recovers. To clear the fault, issue the
RESET_STATUS command.
WLS_MASK
ERR
WLS_FAULT_FLAG
Other Faults
Figure 21. Weak-LED-Supply Fault-Report Topology
7.3.5.6.1 Adjacent-Pin Short Detection
On-demand adjacent-pin short detection is provided. This feature requires off-line diagnostics when the outputs
are disabled. Otherwise, interruptions in normal operation and visual brightness glitches may result.
To start adjacent-pin short detection, set the [ADJ_DIAG_START] bit to HIGH. This bit automatically returns to
LOW when the adjacent pin diagnostic procedure is finished.
After [ADJ_DIAG_START] has been set to HIGH and back to LOW, if any two adjacent pins are shorted, the
[ADJ_FLAG_CHx] bit for the faulty channel is set HIGH. The microcontroller can read [ADJ_FLAG_CHx] to
determine which two adjacent pins are shorted.
Deactivating all the channels by using the [CH_ON_MASKx] bits is suggested before starting adjacent-pin
diagnostics.
when the [ADJ_FLAG_CHx] bit is set, it can only be cleared by issuing the RESET_STATUS command.
7.3.5.6.2 Force Error
To validate the ERR pulldown feedback without a real fault, the [FORCE_ERR] bit is provided to enable an ERR
force-down to simulate a faulty scenario. When [FORCE_ERR] is HIGH, the ERR open-drain output is pulled
down. To clear the fault, issue the RESET_STATUS command.
7.3.5.6.3 Reference Resistor Open and Short Detection
See the Constant-Current Output section.
7.3.5.6.4 PWM Monitor
See the PWM Input section.
Copyright © 2015, Texas Instruments Incorporated
Product Folder Links: TLC6C5712-Q1
Submit Documentation Feedback
19