LP3950SL/NOPB National Semiconductor, LP3950SL/NOPB Datasheet - Page 22

• Manufacturer Part Number: LP3950SL/NOPB
• Description: IC LED DRVR WHITE BCKLGT 32-TSCP
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: Backlight, White LED (I²C Interface)r

Specifications of LP3950SL/NOPB

• Topology: PWM, Step-Up (Boost)
• Number Of Outputs: 6
• Internal Driver: Yes
• Type - Primary: Flash/Torch, LED Blinker, Light Management Unit (LMU)
• Type - Secondary: RGB, White LED
• Frequency: 2MHz
• Voltage - Supply: 2.7 V ~ 2.9 V
• Voltage - Output: 5V
• Mounting Type: Surface Mount
• Package / Case: 32-Laminate TCSP
• Operating Temperature: -40°C ~ 85°C
• Internal Switch(s): Yes
• Efficiency: 90%
• Led Driver Application: Mobile Phone Display Lighting, General LED Lighting
• No. Of Outputs: 6
• Output Current: 300mA
• Output Voltage: 5.3V
• Input Voltage: 3V To 7.2V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output / Channel: -
• Other names: LP3950SL/CSP1; LP3950SLTR

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Audio Synchronization
MODE CONTROL IN THE FREQUENCY MODE
During the frequency mode (SYNC_MODE = 1) the user can
select between two filter options by MODE_CTRL[1:0] as
shown below (Figure 19). User can select the filters based
on the music type and light effect requirements. Filter op-
tions:
MODE_CTRL[1:0] is set to [00], [10] or [11]. Right figure,
narrow frequency response: MODE_CTRL[1:0] set to [01].
Signal passed through the lowpass filter is used to control
the duty cycle of red LEDs (R1 and/or R2 PWM outputs), the
FIGURE 19. Cross-over Frequencies. Left: Wide Frequency Response. Right: Narrow Frequency Response
Left
figure,
wide
FIGURE 18. LP3950 Audio Synchronization Functionality
frequency
(Continued)
response;
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signal passed through the bandpass filter is used to control
green LEDs (G1 and/or G2 PWM outputs) and high pass
signal controls blue LEDs (B1 and/or B2 PWM outputs).
Finally, the user can select the desired mapping speed by
SPEED_CTRL[1:0]. Of course, the user can connect any
color LED to any output in his/her own application (i.e. the
red output does not need to drive a red LED). Maximum duty
cycle is
normal mode of the pattern generator, which is described in
Table RGB LED PWM Control ).
A
100% as in the Flash mode (not 33% as in the
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