Rainbow Electronics MAX8548 - Manual (Page 3)

MAX8545/MAX8546/MAX8548
Low-Cost, Wide Input Range, Step-Down
Controllers with Foldback Current Limit
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(V IN = V L = V CC = 5V, T A = -40°C to +85°C, unless otherwise noted. Typical values are at T A = +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
ERROR AMPLIFIER
2.7V < V CC < 5.5V, 0 °C to +85°C 0.787 0.800 0.815
FB Regulation Voltage
2.7V < V CC < 5.5V, -40 °C to +85°C 0.782 0.800 0.815
V
FB to COMP/EN Gain 4000 V / V
FB to COMP/EN
Transconductance
-5µA < I COMP/EN < +5µA 70 108 160 µS
FB Input Bias Current V FB = 0.88V 1 2 µA
COMP/EN Source Current V COMP/EN = 0V 15 46 100 µA
LX to GND, MAX8545, MAX8548,
V
FB = 0.8V
-355 -320 -280 Current-Limit Threshold Voltage
(Across Low-Side MOSFET)
LX to GND MAX8546, V FB = 0.8V -185 -165 -140
mV
LX to GND, V FB = 0V,
MAX8545, MAX8548
-105 -75 -45
Foldback Current-Limit Threshold
Voltage (Across Low-Side
MOSFET) When Output is Short
MAX8546, LX to GND, V FB = 0 -53 -38 -22
mV
MOSFET DRIVERS
Rising edge, DH going low to DL going high 96
Break-Before-Make Time
Falling edge, DL going low to DH going high 28
ns
DH On-Resistance in Low State 1.6 4 Ω
DH On-Resistance in High State 2.5 5.5 Ω
DL On-Resistance in Low State 1.1 2.5 Ω
DL On-Resistance in High State 2.5 5.5 Ω
BST Leakage Current V BST = 33V, V LX = 28V, V FB = 0.88V 0 50 µA
LX Leakage Current V BST = 33V, V LX = 28V, V FB = 0.88V 33 100 µA
Note 1: Thermal shutdown disables the buck regulator when the die reaches this temperature. Soft-start is reset but the VL regulator
remains on.