LM27964SQ-C/NOPB National Semiconductor, LM27964SQ-C/NOPB Datasheet - Page 12

• Manufacturer Part Number: LM27964SQ-C/NOPB
• Description: IC LED DRIVR WHITE BCKLGT 24-LLP
• Manufacturer: National Semiconductor
• Type: Backlight, White LED (I²C Interface)r
• Series: -r

Specifications of LM27964SQ-C/NOPB

• Constant Current: Yes
• Topology: PWM, Switched Capacitor (Charge Pump)
• Number Of Outputs: 7
• Internal Driver: Yes
• Type - Primary: Backlight, General Purpose
• Type - Secondary: White LED
• Frequency: 500kHz ~ 900kHz
• Voltage - Supply: 2.7 V ~ 5.5 V
• Voltage - Output: 2 V ~ 4 V
• Mounting Type: Surface Mount
• Package / Case: 24-LLP
• Operating Temperature: -30°C ~ 85°C
• Current - Output / Channel: 30mA
• Internal Switch(s): Yes
• Efficiency: 87%
• Led Driver Application: Camera Phone LED Flash, LED Backlight
• No. Of Outputs: 7
• Output Current: 180mA
• Input Voltage: 2.7V To 5.5V
• Operating Temperature Range: -30°C To +85°C
• Rohs Compliant: Yes
• Constant Voltage: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM27964SQ-C; LM27964SQ-C; LM27964SQ-C-TR

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meet the minimum capacitance requirements of the
LM27964.
The minimum voltage rating acceptable for all capacitors is
6.3V. The recommended voltage rating of the output capaci-
tor is 10V to account for DC bias capacitance losses.
PCB LAYOUT CONSIDERATIONS
The LLP is a leadframe based Chip Scale Package (CSP)
with very good thermal properties. This package has an ex-
posed DAP (die attach pad) at the center of the package
12
measuring 2.6mm x 2.5mm. The main advantage of this ex-
posed DAP is to offer lower thermal resistance when it is
soldered to the thermal land on the PCB. For PCB layout,
National highly recommends a 1:1 ratio between the package
and the PCB thermal land. To further enhance thermal con-
ductivity, the PCB thermal land may include vias to a ground
plane. For more detailed instructions on mounting LLP pack-
ages, please refer to National Semiconductor Application
Note AN-1187.