Typical operating characteristics (continued) – Rainbow Electronics MAX17127 User Manual
Page 8
8 ______________________________________________________________________________________
MAX17127
Six-String WLED Driver with Integrated
Step-Up Converter
Typical Operating Characteristics (continued)
(Circuit of Figure 1. V
IN
= 12V, T
A
= +25NC, unless otherwise noted.)
MAXIMUM UNBALANCE RATE BETWEEN STRINGS
(I
LED
= 20mA) vs. INPUT VOLTAGE (V
S
)
MAX17127 toc19
INPUT VOLTAGE (V)
MAXIMUM UNBALANCE RATE (%)
23
20
17
14
11
8
0.3
0.4
0.5
0.6
0.7
0.8
0.2
5
26
MAXIMUM
UNBALANCE RATE (%)
−
=
FB_
FB(AVG) MAX
FB(AVG)
I
I
%
I
MAXIMUM UNBALANCE RATE BETWEEN STRING
vs. BRIGHTNESS (V
S
= 12V, I
LED
= 20mA)
MAX17127 toc18
BRIGHTNESS (%)
MAXIMUM UNBALANCE RATE (%)
80 90
70
60
50
40
30
20
0.2
0.4
0.6
0.8
1.0
0
10
100
MAXIMUM
UNBALANCE RATE (%)
−
=
FB_
FB(AVG) MAX
FB(AVG)
I
I
%
I
LINE-TRANSIENT RESPONSE
(V
S
= 21V 9V, BRIGHTNESS = 100%)
MAX17127 toc17
200µs/div
I
FB1
10mA/div
0V
V
OUT
(AC-COUPLED)
1V/div
V
S
10V/div
0V
0mA
0A
INDUCTOR
CURRENT
1A/div
20mA
9V
21V
LINE-TRANSIENT RESPONSE
(V
S
= 9V 21V, BRIGHTNESS = 100%)
MAX17127 toc16
200µs/div
I
FB1
10mA/div
V
OUT
(AC-COUPLED)
2V/div
0V
V
S
10V/div
0mA
0A
INDUCTOR
CURRENT
1A/div
20mA
9V
21V
0V
LED-SHORT FAULT PROTECTION
(BRIGHTNESS = 100%, 3 LEDs SHORT ON FB1)
MAX17127 toc15
10µs/div
V
FB1
10V/div
I
FB1
50mA/div
0mA
0V