LP5521TM/NOPB National Semiconductor, LP5521TM/NOPB Datasheet - Page 29

• Manufacturer Part Number: LP5521TM/NOPB
• Description: IC LED DRIVER RGB 25-USMD
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: RGB LED Driverr

Specifications of LP5521TM/NOPB

• Constant Current: Yes
• Topology: PWM, Switched Capacitor (Charge Pump)
• Number Of Outputs: 3
• Internal Driver: Yes
• Type - Primary: Backlight, Light Management Unit (LMU)
• Type - Secondary: RGB
• Frequency: 1.25MHz
• Voltage - Supply: 2.7 V ~ 5.5 V
• Voltage - Output: 4.55V
• Mounting Type: Surface Mount
• Package / Case: 20-MicroSMD
• Operating Temperature: -30°C ~ 85°C
• Current - Output / Channel: 25.5mA
• Internal Switch(s): Yes
• Efficiency: 95%
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LP5521TMTR

Direct PWM Control Example
Startup device:
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Enable charge pump 1.5x mode and use internal clock:
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Direct PWM control:
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Write PWM values:
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LEDs are turned on after the PWM values are written. Changes to the PWM value registers are reflected immediately to the LED
brightness. Default LED current (17.5 mA) is used for LED outputs, if no other values are written.
See application note "LP5521 Programming Considerations" for more information.
Supply e.g. 3.6V to VDD
Supply e.g. 1.8V to EN
Write to address 00H 0100 0000b (enable LP5521)
Wait 500 µs (start-up delay)
Write to address 08H 0001 0001b
Write to address 01H 0011 1111b (Configure R, G and B channels into "Direct PWM control mode")
Write to address 02H 1000 0000b (R driver PWM 50% duty cycle)
Write to address 03H 1100 0000b (G driver PWM 75% duty cycle)
Write to address 04H 1111 1111b (B driver PWM 100% duty cycle)
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