User Manual

MAX1540/MAX1541
Dual Step-Down Controllers with Saturation
Protection, Dynamic Output, and Linear Regulator
_______________________________________________________________________________________ 9
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 15V, V
CC
= V
DD
= ON1 = ON2 = 5V, SKIP = GND, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 4)
PARAMETER
SYMBOL
CONDITIONS
MIN MAX
UNITS
0 < I
LDOOUT
< 10mA 4.85 5.10
MAX1541 LDO Output-Voltage
Accuracy (Fixed V
LDOOUT
)
V
LDOOUT
FBLDO = ON1 =
ON2 = GND,
V
LDOIN
= 6V to 28V
0 < I
L D OOU T
< 100m A 4.65 5.10
V
0 < I
LDOOUT
< 10mA 1.212 1.275
MAX1541 LDO Feedback
Accuracy (Adjustable V
LDOOUT
)
V
FBLDO
FBLDO = LDOOUT,
ON1 = ON2 = GND,
V
LDOIN
= 4.5V to
28V
0 < I
L D OOU T
< 100m A 1.175 1.275
V
MAX1540: V+ - V
LDOOUT
800
Dropout Voltage
MAX1541: V
LDOIN
- V
LDOOUT
800
mV
REFERENCE (REF)
Reference Voltage V
REF
V
CC
= 4.5V to 5.5V, I
REF
= 0
1.98 2.02
V
REFIN1 Input Bias Current I
REFIN1
0.05
µA
FAULT DETECTION
Overvoltage Trip Threshold
With respect to error-comparator threshold,
OVP/UVP = V
CC
10 21 %
Output Undervoltage-Protection
Trip Threshold
With respect to error-comparator threshold,
OVP/UVP = V
CC
64 76 %
PGOOD_ Lower Trip Threshold
With respect to error-comparator threshold,
hysteresis = 1%
-14 -5 %
PGOOD_ Upper Trip Threshold
With respect to error-comparator threshold,
hysteresis = 1%
+5
+14
%
PGOOD_ Output Low Voltage I
SINK
= 4mA 0.3 V
V
CC
Undervoltage-Lockout
Threshold
V
UVLO
(
VCC
)
Rising edge, PWM disabled below this
level, hysteresis = 20mV
4.1 4.4 V
CURRENT LIMIT
CSP_ 0 2.7
Current-Limit Input Range
CSN_
-0.3 +28.0
V
Valley Current-Limit Threshold
(Fixed)
V
LIM
_
(
VAL
)
V
CSP
_ - V
CSN
_, ILIM_ = V
CC
40 60 mV
Valley Current-Limit Threshold
(Adjustable)
V
LIM
_
(
VAL
)
V
CSP
_ - V
CSN
_, V
ILIM
_ = 2.00V
160
240 mV
INPUTS AND OUTPUTS
Logic Input Threshold
ON1, ON2, SKIP, GATE, rising edge,
hysteresis = 225mV
1.2 2.2 V
LDOON Input Trip Level Rising edge, hysteresis = 250mV 1.2 1.3 V
High 1.9 2.1
Dual Mode Threshold Voltage
FB1 (MAX1540),
FB2 (MAX1540/MAX1541)
Low
0.05 0.15
V