Datasheet

Multi-Output Power Supplies with VCOM Amplifier
and High-Voltage Gamma Reference for LCD TVs
MAX17126/MAX17126A
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V
INVL
= V
IN2
= 12V, V
VOP
= V
VREF_I
= 15V, T
A
= 0°C to +85°C. Typical values are at T
A
= +25NC, unless oth-
erwise noted.)
Dual Mode is a trademark of Maxim Integrated Products, Inc.
PARAMETER CONDITIONS MIN TYP MAX UNITS
STEP-DOWN REGULATOR
OUT Voltage in Fixed Mode
FB2 = GND, no load
(Note 1)
0°C < T
A
= +85°C 3.25 3.3 3.35
V
T
A
= +25°C 3.267 3.333
FB2 Voltage in Adjustable
Mode
V
OUT
= 2.5V, no load
(Note 1)
0°C < T
A
= +85°C 1.23 1.25 1.27
V
T
A
= +25°C 1.2375 1.2625
FB2 Adjustable Mode
Threshold Voltage
Dual Mode™ comparator 0.10 0.15 0.20 V
Output Voltage Adjust Range 1.5 5 V
FB2 Fault-Trip Level Falling edge 0.96 1.0 1.04 V
FB2 Input Leakage Current V
FB2
= 1.25V 50 125 200 nA
DC Load Regulation 0V < I
LOAD
< 2A 0.5 %
DC Line Regulation No load, 10.8V < V
IN2
< 13.2V 0.1 %/V
LX2-to-IN2 nMOS Switch
On-Resistance
100 200
mI
LX2-to-GND2 nMOS Switch
On-Resistance
6 10 23
I
BST-to-VL pMOS Switch
On-Resistance
40 30 110
I
Low-Frequency Operation
OUT Threshold
LX2 only 0.8 V
Low-Frequency Operation
Switching Frequency
FSEL = INVL 125
kHz
FSEL = GND 83
LX2 Positive Current Limit
MAX17126 2.50 3.20 3.90
A
MAX17126A 3.0 3.5 4.0
Soft-Start Ramp Time Zero to full limit 3 ms
Maximum Duty Factor 70 78 85 %
Minimum Duty Factor
Char/Design Limit Only
10 %
STEP-UP REGULATOR
Output Voltage Range VIN 20 V
Oscillator Maximum Duty Cycle 70 78 85 %
FB1 Regulation Voltage FB1 = COMP, C
COMP
= 1nF 1.2375 1.25 1.2625 V
FB1 Fault Trip Level Falling edge 0.96 1.0 1.04 V
FB1 Load Regulation 0V < I
LOAD
< full 0.5 %
FB1 Line Regulation 10.8V < V
IN
< 13.2V 0.08 %/V
FB1 Input Bias Current V
FB1
= 1.25V 30 125 200 nA
FB1 Transconductance
DI = Q2.5FA at COMP, FB1 = COMP
150 320 560
FS
FB1 Voltage Gain FB1 to COMP 1400 V/V
LX1 Leakage Current V
FB1
= 1.5V, V
LX1
= 20V 10 40
FA