28V Internal Switch LCD Bias Supply
with True Shutdown
ELECTRICAL CHARACTERISTICS (continued)
(V
= 3.3V, V
= BATT = SHDN, T = 0°C to +85°C, unless otherwise noted. Typical values are at T = +25°C.)
CC
CC
A
A
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
CONTROL INPUTS (SHDN, LIM)
SHDN Input Threshold
0.8 ×
V
2.4V ≤ V
2.4V ≤ V
≤ 5.5V
IH
CC
CC
V
CC
V
0.2 ×
V
≤ 5.5V
IL
V
CC
SHDN Input Bias Current
I
V
= 5.5V, V
= 0 to 5.5V
SHDN
-1
+1
µA
V
SHDN
CC
LIM Input Low Level
2.4V ≤ V
≤ 5.5V
0.4
CC
2.4V ≤ V
≤ 5.5V,
(V / 2)
CC
- 0.25V
(V / 2)
CC
+ 0.25V
CC
LIM Input Float Level
LIM Input High Level
LIM Input Bias Current
V
V
I
=
0.5µA
LIM
V
CC
2.4V ≤ V ≤ 5.5V
CC
- 0.4V
SHDN = V , LIM = GND or V
-2
+2
1
CC
CC
I
µA
LIM
SHDN = GND
0.1
PMOS ISOLATION SWITCH (BATT to SW)
PMOS Current Limit
V
V
= 2.5V, V
= 1.5V
0.6
0.75
0.25
1.5
0.4
A
CC
BATT
PMOS On-Resistance
R
= 2.5V, V
= 1.5V, I = 100mA
SW
Ω
DS(ON)
CC
BATT
BATT
V
R
= 2.5V, V
= 50Ω to GND
= 1.5V,
CC
Soft-Start Time
t
0.3
ms
SS
SW
ELECTRICAL CHARACTERISTICS
(V
= 3.3V, V
= BATT = SHDN, T = -40°C to +85°C, unless otherwise noted.) (Note 2)
CC A
CC
PARAMETER
Supply Voltage
SYMBOL
CONDITIONS
MIN
2.4
TYP
MAX
UNITS
V
V
V
(Note 1)
(Note 1)
5.5
CC
CC
BATT Input Voltage Range
V
0.8
V
V
BATT
UVLO
OUT
V
V
V
Undervoltage Lockout
V
V
V
falling, 30mV typical hysteresis
= 1.3V
2.00
2.37
360
1
V
CC
CC
CC
CC
FB
Quiescent Supply Current
Shutdown Supply Current
I
µA
µA
µA
µA
V
CC
SHDN = GND
= 1.3V
BATT Input Supply Current
BATT Shutdown Supply Current
Feedback Set Point
I
V
40
BATT
FB
SHDN = GND
1
V
1.215
1.285
100
FB
Feedback Input Bias Current
I
V
= 1.3V
nA
FB
FB
INDUCTOR CONNECTIONS (LX, SW)
LX Voltage Range
V
28
0.58
0.30
0.17
2
V
A
LX
LIM = V
0.35
0.18
0.08
CC
LX Switch Current Limit
I
LX(MAX)
LIM = floating
LIM = GND
LX On-Resistance
R
V
V
= 3.3V, I = 100mA
LX
Ω
µA
µs
LX
CC
LX
LX Leakage Current
Maximum LX On-Time
= 28V
2
t
9
17
ON
_______________________________________________________________________________________
3
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
