MAX16805 Datasheet, PDF (7/19 Pages) Maxim Integrated Products – EEPROM-Programmable, High-Voltage, 350mA LED Drivers with LED Current Foldback

EEPROM-Programmable, High-Voltage, 350mA
LED Drivers with LED Current Foldback
Typical Operating Characteristics (continued)
(V_IN = 12V, V_EN = V_IN, C_V5 = 0.1µF, I_V5 = 0, CS- = GND, R_SENSE = 0.56Ω, connect OUT to CS+, V_DIM = 4V, SW = VFD = open,
V_TFP/SC = 5V, V_TFN/SD = GND, DGND = GND. T_A = +25°C, unless otherwise noted.)
LED CURRENT FALL TIME (EXPANDED)
MAX16805 toc10
DIM PULSED AT
200Hz
V_DIM
2V/div
0V
I_LED
200mA/div
0A
LED CURRENT RISE TIME (EXPANDED)
MAX16805 toc11
DIM PULSED AT
200Hz
V_DIM
2V/div
0V
I_LED
200mA/div
0A
OUTPUT CURRENT DUTY CYCLE
vs. ANALOG DIM VOLTAGE
120
V_IN = 12V
100 ^{RAMP REGISTER = 0x07}
CFD = GND
TFP = 5V
80 TFN = GND
60
40
20
20µs/div
OUTPUT CURRENT
DUTY CYCLE vs. INPUT VOLTAGE
120
LED CURRENT
THRESHOLD REGISTER = (0x07)
100
20µs/div
0
0
1
2
3
4
V_DIM (V)
OUTPUT CURRENT
DUTY CYCLE vs. INPUT VOLTAGE
120
LED CURRENT
THRESHOLD REGISTER = (0x00)
100
80
BIT3 = 1
60
80
BIT3 = 1
60
40
BIT3 = 0
20
40
20
BIT3 = 0
0
0 2 4 6 8 10 12 14 16 18 20
INPUT VOLTAGE (V)
OUTPUT CLAMP
vs. THERMAL FOLDBACK SLOPE
45
THERMAL SLOPE = 4V/V
40
35
THERMAL SLOPE = 4V/V
30
25
THERMAL SLOPE = 8V/V
20
THERMAL SLOPE = 12V/V
15
10
5 THERMAL FOLDBACK
CLAMP LEVEL = 40%
0
0 0.2 0.4 0.6 0.8 1.0
V_TFN (V)
THERMAL
KNEE = +60°C
1.2 1.4 1.6
0
0 5 10 15 20 25 30
INPUT VOLTAGE (V)
OUTPUT RESPONSE TO SW INPUT
MAX16805 toc16
DEBOUNCE
TIME
DEBOUNCE
TIME
V_SW
5V/div
V_SENSE
200mV/div
40ms/div
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