LP3936SL National Semiconductor, LP3936SL Datasheet - Page 18

• Manufacturer Part Number: LP3936SL
• Manufacturer: National Semiconductor

Specifications of LP3936SL

• Operating Supply Voltage (typ): 3.3/5V
• Number Of Segments: 6
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Package Type: LAM CSP
• Pin Count: 32
• Mounting: Surface Mount
• Operating Supply Voltage (min): 3V
• Operating Supply Voltage (max): 6V
• Lead Free Status / Rohs Status: Compliant

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I
I
I
I
RANGE
MAX
LEAKAGE
MATCH
EN_RED_PWM
EN_GREEN_PWM
EN_BLUE_PWM
RGB LED PWM Control
Note 13: Application Note AN-1293, “Driving RGB LEDs Using LP3936 Lighting Management System” contains a thorough description of the RGB driver
functionality including programming examples.
WLED Drivers
White LED drivers drive each white LED with a regulated
constant current. The outputs are combined in two groups,
four outputs for the main display backlight and two outputs
for the sub display backlight. The current is controlled be-
tween 0 and 25.5 mA using the 8-bit current mode DA-
converters. WLED outputs can be used to drive any kind of
LED.
WLED and CLED Driver Electrical Characteristics
Note 14: A minimum voltage, Dropout Voltage, is required on the WLED outputs for maintaining the LED current. The current reduction at lower voltages is shown
in the graph WLED Output Current vs. Voltage.
Note 15: Match % = 100% * (Max – Min)/Min
Symbol
Sink Current Range
Maximum Sink Current
Leakage Current
Sink Current Matching
(Note 15)
EN_X_PWM = 0 → External PWM control from RGB_EN pin is disabled
EN_X_PWM = 1 → External PWM control from RGB_EN pin is enabled
Internal PWM control (DUTY) can be used independently of external PWM control. External PWM has
the same effect on all enabled colors.
Parameter
(Note 13) (Continued)
V
(Note 14)
V
I
WLED1 … 4 or WLED5 … 6
SINK
FB
FB
= 4.55V, Control 00h–FFh
= 5V
= 13 mA, between
Conditions
18
Main and sub display outputs have separate enable control
bits, EN_4LED and EN_2LED.
PWM control of WLED outputs for dimming or on/off control
is
EN_4LED_PWM and EN_2LED_PWM enable control bits
from the user register. Recommended maximum frequency
of WLED external PWM control is 1 kHz.
possible
using
Min
24
22
RGB_EN
20081430
0–25.5
25.5
0.04
Typ
1.0
pin
together
Max
27
28
1
4
Units
with
mA
mA
mA
µA
%