EVALED7706 STMicroelectronics, EVALED7706 Datasheet - Page 21

• Manufacturer Part Number: EVALED7706
• Description: EVALUATION BOARD FOR LED7706
• Manufacturer: STMicroelectronics

Specifications of EVALED7706

• Current - Output / Channel: 30mA
• Outputs And Type: 6, Non-Isolated
• Voltage - Output: 36 V
• Features: Dimmable, Extra 5V Output
• Voltage - Input: 4.5 ~ 36 V
• Utilized Ic / Part: LED7706
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6445

LED7706
5.3
5.3.1
5.3.2
Fault management
The main loop keeps the row having the lowest voltage drop regulated to about 400 mV.
This value slightly depends on the voltage across the remaining active rows. After the soft-
start sequence, all protections turn active and the voltage across the active current
generators is monitored to detect shorted LEDs.
FAULT pin
The FAULT pin is an open-collector output, (with 4 mA current capability) active low, which
gives information regarding faulty conditions eventually detected. This pin can be used
either to drive a status LED or to warn the host system.
The FAULT pin status is strictly related to the MODE pin setting (see
MODE pin
The MODE pin is a digital input and can be connected to AVCC or SGND in order to choose
the desired fault detection and management. The LED7706 can manage a faulty condition
in two different ways, according to the application needs.
device detects and handles the internal protections related to the boost section (over-
current, over-temperature and over-voltage) and to the current generators section (open and
shorted LEDs).
Table 6.
Internal MOSFET over
LED short shorted led
Output over voltage
Thermal shutdown
Open row(s)
current
FAULT
Faults management summary
occurrence, latched condition
Device turned OFF at first
Device turned OFF,
latched condition
FAULT pin LOW
FAULT pin LOW
MODE to GND
(Vth = 3.4 V)
Automatic restart after 30 C temperature drop.
Device turned OFF, latched condition
FAULT pin LOW. Device turned OFF.
Power MOS turned OFF
FAULT pin HIGH
FAULT pin LOW
Table 6
Device keeps on working with the
Device keeps on working with the
FAULT pin HIGH Faulty row(s)
Faulty row(s) disconnected
summarizes how the
remaining row(s)
remaining row(s)
FAULT pin LOW
MODE to VCC
Operation description
disconnected.
Table 6
(Vth = 6 V)
for details).
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