PM6600 STMicroelectronics, PM6600 Datasheet - Page 39

• Manufacturer Part Number: PM6600
• Description: IC LED DRIVR WHT BCKLT 24-VFQFPN
• Manufacturer: STMicroelectronics
• Type: Backlight, White LEDr

Specifications of PM6600

• Topology: PWM, Step-Up (Boost)
• Number Of Outputs: 6
• Internal Driver: Yes
• Type - Primary: Backlight
• Type - Secondary: White LED
• Frequency: 200kHz ~ 1MHz
• Voltage - Supply: 4.7 V ~ 28 V
• Voltage - Output: 36V
• Mounting Type: Surface Mount
• Package / Case: 24-VFQFN, 24-VFQFPN
• Operating Temperature: -40°C ~ 85°C
• Current - Output / Channel: 32mA
• Internal Switch(s): Yes
• Number Of Segments: 60
• Operating Supply Voltage: 4.7 V to 28 V
• Maximum Power Dissipation: 2.3 W
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• For Use With: 497-8414 - BOARD EVAL BASED ON PM6600
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Efficiency: -
• Lead Free Status / Rohs Status: Details

PM6600
9
9.1
9.2
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, active low, which gives information regarding
faulty conditions eventually detected. This pin can be used either to drive a status LED (with
a series resistor to not exceed 4 mA current) 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 PM6600 can manage a faulty condition in
two different ways, according to the application needs.
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 8.
Shorted LEDs on more rows
Open rows plus shorted led
Shorted LEDs on a single
Internal MOSFET over
Output over voltage
Thermal shutdown
(different rows)
More than one
open rows
Open row
current
FAULT
row
Faults management summary
Doc ID 14248 Rev 7
device turned OFF latched
device turned OFF latched
power-MOS turned OFF
faulty ROW DISABLED
faulty ROW DISABLED
VTH,FAULT = 8.2 V
device latched OFF
VTH,FAULT = 8.2 V
device latched OFF
device latched OFF
VTH,FAULT = 8.2 V
FAULT pin HIGH
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
MODE to GND
Table 8
Table 8
for details).
summarizes how the device
device turned OFF latched
device turned OFF latched
power-MOS turned OFF
faulty ROWs DISABLED
faulty ROWs DISABLED
faulty ROWs DISABLED
faulty ROW DISABLED
faulty ROW DISABLED
VTH,FAULT = 8.2 V
VTH,FAULT = 8.2 V
VTH,FAULT = 8.2 V
FAULT pin HIGH
FAULT pin HIGH
FAULT pin HIGH
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
FAULT pin LOW
MODE to VCC
Fault management
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