LP5521TM/NOPB National Semiconductor, LP5521TM/NOPB Datasheet - Page 18

• 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

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DIRECT Control
When R, G or B channel mode is set to 00b, the LP5521
drivers work in direct control mode. LP5521 LED channels
can be controlled independently through I
nel there is a PWM control register and a output current
If charge pump automatic gain change is used in this mode,
then PWM values need to be written 0 before changing the
Name
PWM
R_PWM register (02H), G_PWM register (03H), B_PWM register (04H):
Bit
7:0
2
C. For each chan-
Description
LED PWM value during direct control operation mode
0000 0000b = 0%
1111 1111b = 100%
18
control register. With output current control register is set what
is the maximum output current with 8-bit resolution, step size
is 100 μA. Duty cycle can be set with 8-bit resolution. Direct
control mode resets respective channel’s PC. PWM control
bits are presented in following table:
drivers’ operation mode to disabled (00b) to ensure proper
automatic gain change operation.