PM6600 STMicroelectronics, PM6600 Datasheet - Page 29

• 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
Operation description
The SYNC pin is a synchronization output and provides a 34% (typ.) duty-cycle clock when
the PM6600 is used as master or a replica of the FSW pin when used as slave. It is used to
connect multiple devices in a daisy-chain configuration or to synchronize other switching
converters running in the system with the PM6600 (master operation).
When an external synchronization clock is applied to the FSW pin, the internal oscillator is
over-driven: each switching cycle begins at the rising edge of clock, while the slope
compensation ramp starts at the falling edge of the same signal. Thus, the external
synchronization clock is required to have a 40% maximum duty-cycle when the boost
converter is working in continuous-conduction mode (CCM). The minimum pulse width
which allows the synchronizing pulses to be detected is 270 ns.
Figure 46. External sync waveforms
270ns minimum
FSW pin voltage (ext. sync)
300mV threshold
Slave SYNC pin voltage
Slave LX pin voltage
Doc ID 14248 Rev 7
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