Datasheet

Step-Up, Step-Down Regulator, Gate-On Charge Pump,
and Boost-Buck Regulator for TV TFT LCD Display
MAX17122
_______________________________________________________________________________________ 9
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
STEP-DOWN REGULATOR EFFICIENCY
vs. LOAD CURRENT
MAX17122 toc01
LOAD CURRENT (A)
EFFICIENCY (%)
1
65
70
75
80
85
90
60
0.10 10
V
IN
= 10V
V
IN
= 12V
STEP-DOWN REGULATOR NORMALIZED
OUTPUT VOLTAGE vs. LOAD CURRENT
MAX17122 toc02
LOAD CURRENT (A)
OUTPUT-VOLTAGE ERROR (%)
2.01.61.20.80.4
-1.2
-1.0
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
-1.4
0 2.4
V
IN
= 12V
V
IN
= 10V
STEP-DOWN REGULATOR LOAD-TRANSIENT
RESPONSE (0.2A TO 1.7A)
MAX17122 toc03
V
OUTB
(AC-COUPLED)
200mV/div
I
LOAD
1A/div
I
L2
1A/div
0A
0A
L = 4.7µH
0V
20µs/div
STEP-UP REGULATOR EFFICIENCY
vs. LOAD CURRENT
MAX17122 toc04
LOAD CURRENT (A)
EFFICIENCY (%)
10.10
82
84
86
88
90
92
94
96
80
0.01 10
V
IN
= 12V
V
IN
= 10V
STEP-UP REGULATOR NORMALIZED
OUTPUT VOLTAGE vs. LOAD CURRENT
MAX17122 toc05
LOAD CURRENT (A)
OUTPUT-VOLTAGE ERROR (%)
2.01.51.00.5
-0.30
-0.25
-0.20
-0.15
-0.10
-0.05
0
0.05
0.10
-0.35
0 2.5
V
IN
= 10V
V
IN
= 12V
STEP-UP REGULATOR LOAD-TRANSIENT
RESPONSE (0.2A TO 1.2A)
MAX17122 toc06
V
AVDD
(AC-COUPLED)
200mV/div
I
LOAD
1A/div
I
L1
1A/div
0A
0A
L1 = 4.7µH
C
COMP1
= 330pF
R
COMP1
= 39.2kI
C
COMP1P
= 10pF
0V
40µs/div