MAX8543/MAX8544
Step-Down Controllers with Prebias Startup,
Lossless Sensing, Synchronization, and OVP
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= 13.2V, V
BST
- V
LX
= 5V, T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.)
POK
Power-OK Threshold
V
FB
rising, percent of V
OUT
,
typical hysteresis is 3%
88 91 94 %
POK Output Voltage, Low V
FB
= 0.6V, I
POK
= 2mA 25
200
mV
POK Leakage Current, High V
POK
= 5.5V
0.001
1 µA
OVERVOLTAGE PROTECTION (OVP)
Output Overvoltage Fault-Trip level
Rising edge compared to regulation set point;
triggers after one or two clock cycles
+110 +115 +120
%
MODE CONTROL
MODE Logic-Level Low 3V ≤ V
VL
≤ 5.5V 0.4 V
MODE Logic-Level High 3V ≤ V
VL
≤ 5.5V
1.8 V
V
MODE
= 0V -1 +1
MODE Input Current
MODE = VL 5 10
µA
SHUTDOWN CONTROL
EN Logic-Level Low 3V ≤ V
VL
≤ 5.5V
0.45
V
EN Logic-Level High 3V ≤ V
VL
≤ 5.5V 2 V
V
EN
= 0 or 5.5V -1 +4
EN Input Current
V
EN
= 13.2V 1.5 6
µA
ELECTRICAL CHARACTERISTICS
(V
IN
= 13.2V, V
BST
- V
LX
= 5V, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 2)
MIN
MAX
Operating Input Voltage Range VL connected to IN for V
IN
< 5.5V 3.0
13.2
V
Quiescent Supply Current V
FB
= 0.9V, no switching 3 mA
EN = GND, MODE = GND, IN not connected to VL
10
Shutdown Supply Current
EN = GND, VL = IN, MODE = GND 20
µA
VL Undervoltage-Lockout Trip Level V
VL
rising, typical hysteresis is 80mV
2.52
2.88
V
Output Voltage Adjust Range (V
OUT
) (Note 1) 0.8 V
VL Output Voltage 5.5V < V
IN
< 13.2V, 1mA < I
VL
< 75mA 4.5 5.5 V
VL Output Current 75 mA
VOLTAGE REFERENCE
SS Shutdown Resistance From SS to GND, V
EN
= 0V 100 Ω
SS Soft-Start Current V
REF
= 0.625V 14 34 µA
ERROR AMPLIFIER
FB Regulation Voltage
0.788
0.808
V
Transconductance 70 160 µS
COMP Shutdown Resistance From COMP to GND, V
EN
= 0V 100 Ω
FB Input Leakage Current V
FB
= 0.9V 100 nA
FB Input Common-Mode Range
-0.1
+0.9
