Rainbow Electronics MAX16831 - Manual (Page 7)

MAX16831
High-Voltage, High-Power LED Driver with
Analog and PWM Dimming Control
_______________________________________________________________________________________ 7
Typical Operating Characteristics (continued)
(V CC = V UVEN = 14V, C REG1 = 1µF, C REG2 = 10µF, C CLMP = 0.1µF, R T = 25kΩ, R CS = 0.1Ω, T A = +25°C, unless otherwise noted.)
100
200
250
300
350
400
450
500
550
0.005 0.015 0.025 0.035 0.045
PWM OSCILLATOR FREQUENCY
vs. 1/RT CONDUCTANCE
MAX16831 toc13
1/RT (k Ω -1 )
PWM FREQUENCY (kHz)
150
2ms/div
200Hz DIMMING OPERATION
10% DIMMING
1A/div
MAX16831 toc14
0A
50% DIMMING
1A/div
0A
90% DIMMING
1A/div
0A
0
30
40
50
60
70
80
90
100
0 1 2 3
LED CURRENT DUTY CYCLE
vs. DIM VOLTAGE
MAX16831 toc15
DIM VOLTAGE (V)
LED CURRENT DUTY CYCLE (%) 20
10
40ns/div
DRIVER (DRV) RISE TIME
DRV OUTPUT
RISING
MAX16831 toc16
2V/div
0V
5nF CAPACITOR CONNECTED
FROM DRV TO AGND
40ns/div
DRIVER (DRV) FALL TIME
DRV OUTPUT
FALLING
MAX16831 toc17
2V/div
0V
5nF CAPACITOR CONNECTED
FROM DRV TO AGND
40ns/div
DGT RISE TIME
DGT OUTPUT
RISING
14V OFFSET
MAX16831 toc18
2V/div
14V
V HI - V LO = 11V
1nF CAPACITOR CONNECTED
FROM DGT TO AGND
40ns/div
DGT FALL TIME
DGT OUTPUT
FALLING
14V OFFSET
MAX16831 toc19
2V/div
14V
V HI - V LO = 11V
1nF CAPACITOR CONNECTED
FROM DGT TO AGND