Datasheet

MAX1748/MAX8726
Triple-Output TFT-LCD
DC-DC Converters
4 _______________________________________________________________________________________
PARAMETER
SYMBOL
CONDITIONS
MIN
MAX
UNITS
Input Supply Range V
IN
2.7 5.5 V
Input Undervoltage Threshold
V
UVLO
V
IN
rising, 40mV hysteresis (typ) 2.2 2.6 V
IN Quiescent Supply Current I
IN
V
FB
= V
FBP
= 1.5V, V
FBN
= -0.2V 1 mA
SUPP Quiescent Current
I
SUPP
V
FBP
= 1.5V 0.8 mA
SUPN Quiescent Current
I
SUPN
V
FBN
= -0.1V 0.8 mA
IN Shutdown Current V
SHDN
= 0, V
IN
= 5V 10 µA
SUPP Shutdown Current V
SHDN
= 0, V
SUPP
= 13V 10 µA
SUPN Shutdown Current V
SHDN
= 0, V
SUPN
= 13V 10 µA
MAIN BOOST CONVERTER
Output Voltage Range
V
MAIN
V
IN
13.0
V
FB Regulation Voltage V
FB
1.222 1.271
V
FB Input Bias Current I
FB
V
FB
= 1.25V, INTG = GND -50
+50
nA
Operating Frequency F
OSC
0.75 1.25
MHz
Oscillator Maximum Duty Cycle
78 90 %
LX Switch On-Resistance
R
LX
(
ON
)
I
LX
= 100mA 0.7 Ω
LX Leakage Current
I
LX
V
LX
= 13V 20 µA
Phase I = soft-start (1.0ms)
0.275 0.500
LX Current Limit
I
LX
(
MAX
)
Phase IV = fully on (after 3.0ms) 1.1 2.0
A
FB Fault Trip Level
1.07 1.14
V
POSITIVE CHARGE PUMP
SUPP Input Supply Range
V
SUPP
2.7
13.0
V
FBP Regulation Voltage V
FBP
1.20 1.30
V
FBP Input Bias Current I
FBP
V
FBP
= 1.5V -50
+50
nA
DRVP PCH On-Resistance 10 Ω
V
FBP
= 1.213V 4 Ω
DRVP NCH On-Resistance
V
FBP
= 1.275V 20 kΩ
FBP Power-Ready Trip Level Rising edge
1.091 1.159
V
NEGATIVE CHARGE PUMP
SUPN Input Supply Range
V
SUPN
2.7
13.0
V
FBN Regulation Voltage V
FBN
-50
+50
mV
FBN Input Bias Current
I
FBN
V
FBN
= -0.05V -50
+50
nA
DRVN PCH On-Resistance
10 Ω
V
FBN
= 0.035V 4 Ω
DRVN NCH On-Resistance
V
FBN
= -0.025V 20 kΩ
FBN Power-Ready Trip Level Rising edge 80
165
mV
REFERENCE
Reference Voltage V
REF
-2µA < I
REF
< +50µA
1.223 1.269
V
Reference Undervoltage
V
REF
rising 0.9 1.2 V
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= +3.0V, SHDN = IN, V
SUPP
= V
SUPN
= 10V, TGND = PGND = GND, C
REF
= 0.22µF, C
INTG
= 470pF, T
A
= -40°C to +85°C,
unless otherwise noted.) (Note 1)