LP3936SL National Semiconductor, LP3936SL Datasheet - Page 17

• 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

R
I
I
T
T
T
T
Duty
T
D
D
D
D
F
F
LEAKAGE
MAX
RDUTY[3:0]
GDUTY[3:0]
BDUTY[3:0]
RSLOPE[3:0]
GSLOPE[3:0]
BSLOPE[3:0]
RON[6:0]
GON[6:0]
BON[6:0]
ROFF[6:0]
GOFF[6:0]
BOFF[6:0]
CYCLE[1:0]
RSW
GSW
BSW
RGB_START
RGB_PWM
EN_FLASH
SMAX
SMIN
SRES
START/STOP
BLINK
PWMF
PWM
DS-ON
CYCF
CYC
RESF
RES
RGB Driver Electrical Characteristics
(R
Note 12: The total load current of the boost converter should be limited to 250 mA.
RGB LED PWM Control
Symbol
OUT
, G
OUT
, B
ON Resistance
Off State Leakage Current
Maximum Sink Current
Maximum Slope Period
Minimum Slope Period
Slope Resolution
Start/Stop Resolution
Duty Step Size
Blinking Cycle Accuracy
Duty Cycle Range
Duty Cycle Range
Duty Resolution
Duty Resolution
PWM Frequency
PWM Frequency
OUT
outputs)
DUTY sets the brightness of the LED by adjusting the duty cycle of the PWM driver. The minimum DUTY
cycle [0000] is 0% and the maximum [1111] in the Flash mode is
the peak pulse current. The peak pulse current is determined by the external resistor, LED forward
voltage drop and the boost voltage.
SLOPE sets the turn-on and turn-off slopes. Fastest slope is set by [0000] and slowest by [1111]. SLOPE
changes the duty cycle at constant, programmable rate. For each slope setting the maximum slope time
appears at maximum DUTY setting. When DUTY is reduced, the slope time decreases proportionally. For
example, in case of maximum DUTY, the sloping time can be adjusted from 31 ms [0000] to 930 ms
[1111]. For 50% DUTY [1000] the sloping time is 17 ms [0000] to 496 ms [1111]. The blinking cycle has
no effect on SLOPE.
ON sets the beginning time of the turn-on slope. The on-time is relative to the selected blinking cycle
length. On-setting N (N = 0–127) sets the on-time to N/128 * cycle length.
OFF sets the beginning time of the turn-off slope. Off-time is relative to blinking cycle length in the same
way as on-time.
If ON = 0, OFF = 0 and RGB_PWM = 1, then RGB outputs are continuously on (no blinking), DUTY
controls the brightness and SLOPE is ignored.
If ON and OFF are the same, but not 0, RGB outputs are turned off.
CYCLE sets the blinking cycle: [00] for 0.25s, [01] for 0.5s, [10] for 1s and [11] for 2s. CYCLE setting is
common to all R, G and B drivers.
Enable for R switch
Enable for G switch
Enable for B switch
Master Switch:
RGB_PWM = 0 → RSW, GWS and BSW control directly the RGB outputs (on/off control only)
RGB_PWM = 1 → Normal PWM RGB functionality (duty, slope, on/off times, cycle)
Flash Mode enable control for RGB. In Flash mode (EN_FLASH = 1) RGB outputs are PWM controlled
simultaneously, not in 3-phase system as in the Normal Mode.
RGB_START = 0 → RGB OFF
RGB_START = 1 → RGB ON, starts the new cycle from t = 0
Parameter
(Note 13)
V
(Note 12)
Maximum Duty Setting
Maximum Duty Setting
Maximum Duty Setting
Cycle 1s
EN_FLASH = 1
EN_FLASH = 0
EN_FLASH = 1 (4-bit)
EN_FLASH = 0 (4-bit)
EN_FLASH = 1
EN_FLASH = 0
FB
= 5.3V
Conditions
17
Min
−6
A
0
0
94% and in the normal mode 31% of
0.04
0.93
1/16
1/16
6.27
2.09
6.67
Typ
±
31
62
20
2
3
Max
120
4.5
+6
94
31
1
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Units
kHz
kHz
mA
ms
ms
µA
%
%
%
%
%
Ω
s
s