Datasheet

MAX1954A
Low-Cost, Current-Mode PWM Buck
Controller with Foldback Current Limit
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= 5V, V
BST
- V
LX
= 5V, T
A
= 0°C to +85°C, unless otherwise noted.)
PARAMETER CONDITIONS
MIN
TYP
MAX
UNITS
SOFT-START
Soft-Start Period 3.4 ms
Soft-Start Levels
12.5
mV
FET DRIVERS
DH, DL Output Low Voltage I
SINK
= 10mA 0.1 V
DH, DL Output High Voltage I
SOURCE
= 10mA
V
IN
- 0.1V or
V
BS T
- 0.1V
V
DH Pullup/Pulldown,
DL Pullup On-Resistance
1.5 3 Ω
DL Pulldown On-Resistance 1 2 Ω
LX, BST, HSD Leakage Current V
BST
= 18.7V, V
LX
= 13.2V, V
IN
= 5.5V, V
HSD
= 13.2V 30 µA
THERMAL PROTECTION
Thermal Shutdown Rising temperature, 15°C hysteresis
+160
°C
SHUTDOWN CONTROL
COMP Logic-Level Low 3V < V
IN
< 5.5V
0.25
V
COMP Logic-Level High 3V < V
IN
< 5.5V 0.8 V
COMP Pullup Current
100
µA
ELECTRICAL CHARACTERISTICS
(V
IN
= 5V, V
BST
- V
LX
= 5V, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 2)
PARAMETER CONDITIONS
MIN MAX
UNITS
GENERAL
Operating Input Voltage Range
3.0 5.5 V
HSD Voltage Range (Note 1) 3.0
13.2
V
Quiescent Supply Current V
FB
= 1.5V 2
mA
Standby Supply Current
V
IN
= V
BST
= 5.5V, V
HSD
= 13.2V, LX = unconnected,
COMP = GND
2
mA
Undervoltage Lockout Trip Level
Rising V
IN
3% (typ) hysteresis
2.50 2.93
V
DC-DC CONTROLLER
Output-Voltage Adjust Range
(V
OUT
)
0.8
0.9 x V
IN
V
ERROR AMPLIFIER
FB Regulation Voltage
-2.5 +1.0
%
Transconductance 70
160
µS
FB Input Leakage Current V
FB
= 0.9V
500
NA
FB Input Common-Mode Range -0.1 +1.5
V
COMP Output-Voltage Swing 0.8 2.2 V