LP3950SL/NOPB National Semiconductor, LP3950SL/NOPB Datasheet - Page 14

• 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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RDS
f
t
t
I
Symbol
PWF
PULSE
STARTUP
CL_OUT
Magnetic Boost DC/DC Converter Electrical Characteristics
Limits in standard typeface are for T
(−40˚C ≤ T
C
Boost Standby Mode
User can set the boost converter to STANDBY mode by writing the register bit EN_BOOST low when there is no load to avoid
idle current consumption. When EN_BOOST is written high, the converter starts in PFM (Pulse Frequency Modulation) mode for
10 ms and then goes to PWM (Pulse Width Modulation ) mode. All RGB outputs are off during the 10 ms delay.
Boost Output Voltage Control
User can control the boost output voltage by eight-bit boost output voltage register according to the following table.
Boost Frequency Control
The register ‘boost frequency’ has address 0C’h. The default value after reset is 07’h. ‘x’ means don’t care.
VDD2
ON
= C
Switch ON Resistance
PWM Mode Switching
Frequency
Frequency Accuracy
Switch Pulse Minimum
Width
Startup Time
SW Pin Current Limit
0000 0000
0000 0001
0000 0011
0000 0111
0000 1111
FREQ_SEL[2:0]
VDDA
Register 0D’h
A
Binary
BOOST[7:0]
≤ +85˚C). Unless otherwise noted, specifications apply to Figure 1 with: V
= C
1xx
01x
Parameter
VDDIO
Hex
0F
00
01
03
07
= 100 nF, C
BOOST Output
Frequency
2.00 MHz
1.67 MHz
J
(typical)
Voltage
= +25˚C. Limits in boldface type apply over the operating ambient temperature range
OUT
V
RT = 82 kΩ
freq_sel[2:0] = 1XX
2.7 ≤ VDD
RT = 82 kΩ
No Load
4.10
4.25
4.40
4.55
4.70
DD1,2
= C
= 2.8V, I
IN
= 10 µF, C
1,2
≤ 2.9
Conditions
SW
= 0.5A
VREF
14
= 100 nF, L
0001 1111
0011 1111
0111 1111
1111 1111
1
FREQ_SEL[2:0]
Register 0D’h
Binary
= 4.7 µH and f
BOOST[7:0]
001
Min
700
500
−6
−9
DD1
= V
Hex
1F
3F
7F
FF
BOOST
DD2
= V
Typ
800
0.4
2.0
±
25
15
= 2.0 MHz (Note 12).
BOOST Output
(Continued)
3
5.00 Default
Frequency
DDA
1.00 MHz
(typical)
Voltage
4.85
5.15
5.30
= 2.8V, C
1000
Max
900
0.7
+6
+9
VDD1
=
Units
MHz
mA
ms
ns
%
Ω