LM3697_15 Datasheet, PDF (30/43 Pages) Texas Instruments – High-Efficiency Three-String White LED Driver

LM3697
SNOSCS2C – NOVEMBER 2013 – REVISED OCTOBER 2015
www.ti.com
V_IN = 3.6 V, full-scale current = 20.2 mA, LEDs are WLEDs part # SML-312WBCW(A), Typical Application Circuit , T_A = 25°C
unless otherwise specified. Efficiency is V_OUT × (I_HVLED1 + I_HVLED2 + I_HVLED3)/(V_IN × I_IN), matching curves are (ΔI_{LED_MAX}/I_{LED_AVE}).
7.00%
6.00%
5.00%
4.00%
3.00%
2.00%
1.00%
0.00%
-1.00%
m1-2
m2-3
m3-1
30.0
28.0
26.0
24.0
22.0
20.0
18.0
16.0
14.0
12.0
10.0
8.0
6.0
4.0
2.0
0.0
-40C
25C
90C
BRIGHTNESS CODE
C001
Linear Mapping
Figure 48. H_VLED Matching Vs. Brightness Code
1.70
1.50
1.30
1.10
0.90
0.70
90C
-40C
25C
0.50
VHR (V)
C001
Figure 49. H_VLED Current vs. Current Sink Headroom
Voltage
1.01
1.00
0.99
0.98
0.97
0.96
0.95
0.94
0.93
0.92
90C
0.91
25C
0.90
-40C
VIN (V)
C001
VIN (V)
C001
Figure 50. Shutdown Current vs. V_IN
100.00%
Figure 51. Open Loop Current Limit vs. V_IN
10.00%
1.00%
0.10%
0.01%
PWM FREQUENCY (Hz)
C001
Figure 52. Led Current Ripple vs F_PWM
8s2p LED configuration
Figure 53. Start-up Response
30
Submit Documentation Feedback
Product Folder Links: LM3697
Copyright © 2013–2015, Texas Instruments Incorporated