PM6600 STMicroelectronics, PM6600 Datasheet - Page 28

• 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

Operation description
7.3
28/60
Figure 44. OVP threshold setting
Switching frequency selection and synchronization
The switching frequency of the boost converter can be set in the 200 kHz-1 MHz range by
connecting the FSW pin to ground through a resistor. Calculation of the setting resistor is
made using equation 3 and should not exceed the 80 kΩ-400 kΩ range.
Equation 6
In addition, when the FSW pin is tied to AVCC, the PM6600 uses a default 660 kHz fixed
switching frequency, allowing to save a resistor in minimum components-count applications.
Figure 45. Multiple device synchronization
The FSW pin can also be used as a synchronization input, allowing the PM6600 to operate
both as master or slave device. If a clock signal with a 210 kHz minimum frequency is
applied to this pin, the device locks synchronized (300 mV threshold). An Internal time-out
allows synchronization as long as the external clock frequency is greater than 210 kHz.
Keeping the FSW pin voltage lower than 300 mV for more than 1/210 kHz
the device turn off. Normal operation is resumed as soon as FSW rises above the
mentioned threshold and the soft-start sequence is repeated.
R
FSW
FSW
AVCC
V
IN
PM6600
MASTER
SGND
Doc ID 14248 Rev 7
PM6600
SYNC
R
SGND
FSW
LX
OVSEL
=
f
2
SW
5 .
FSW
R
R
2
1
PM6600
V
SLAVE
OUT
C
C
SYNC
13
10
SGND
C
OUT
SYNC
≈
5 μs results in
Sync Out
PM6600