MAX1540A Datasheet, PDF (6/49 Pages) Maxim Integrated Products – Dual Step-Down Controllers with Saturation Protection, Dynamic Output, and Linear Regulator

Dual Step-Down Controllers with Saturation
Protection, Dynamic Output, and Linear Regulator
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 15V, V_CC = V_DD = ON1 = ON2 = 5V, SKIP = GND, LDOIN (MAX1541) = V+, T_A = 0°C to +85°C, unless otherwise noted. Typical
values are at T_A = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX UNITS
Valley Current-Limit Threshold
(Fixed)
V_LIM_ _(VAL) V_CSP_ - V_CSN_, ILIM_ = V_CC
45
50
55
mV
Valley Current-Limit Threshold
(Adjustable)
Current-Limit Threshold
(Negative)
V_LIM_ _(VAL) V_CSP_ - V_CSN_
V_ILIM_ = 250mV
V_ILIM_ = 2.00V
V_NEG
V_CSP_ - V_CSN _, SKIP = ILIM_ = V_CC,
T_A = +25°C
15
25
35
mV
170
200
230
-90
-65
-45
mV
Current-Limit Threshold
(Zero Crossing)
With respect to valley current-limit
V_ZX
threshold, V_CSP_ - V_CSN _, SKIP = GND,
ILIM_ = V_CC
2.5
mV
Inductor-Saturation Current-Limit
Threshold
With respect to
valley current-
limit threshold,
ILIM_ = V_CC
LSAT = V_CC
LSAT = open
LSAT = REF
180
200
220
157
175
193
%
135
150
165
ILIM_ Saturation Fault Sink
Current
I_ILIM_ _(LSAT)
V_CSP - V_CSN > inductor saturation current
limit, 0.25V < V_ILIM_ < 2.0V
4
6
8
µA
ILIM_ Leakage Current
V_CSP_ - V_CSN _ < inductor saturation current
limit
0.1
µA
GATE DRIVERS
DH_ Gate-Driver On-Resistance
DL_ Gate-Driver On-Resistance
R_DH BST_-LX_ forced to 5V
DL_, high state
R_DL
DL_, low state
1.5
5
Ω
1.5
5
Ω
0.6
3
DH_ Gate-Driver Source/Sink
Current
I_DH
DH_ forced to 2.5V, BST_-LX_ forced to 5V
1
A
DL_ Gate-Driver Source Current
DL_ Gate-Driver Sink Current
Dead Time
INPUTS AND OUTPUTS
OD On-Resistance
OD Leakage Current
Logic Input Threshold
LDOON Input Trip Level
Logic Input Current
I_DL
(SOURCE)
I_{DL (SINK)}
t_DEAD
DL_ forced to 2.5V
DL_ forced to 2.5V
DL_ rising
DH_ rising
R_OD
GATE = V_CC
GATE = GND, OD forced to 5.5V
ON1, ON2, SKIP, GATE rising edge,
hysteresis = 225mV
Rising edge, hysteresis = 250mV
ON1, ON2, LDOON, SKIP, GATE
1
A
3
A
35
ns
26
10
25
Ω
1
200
nA
1.2
1.7
2.2
V
1.20 1.25 1.30
V
-1
+1
µA
Dual Mode™ Threshold Voltage
FB1 (MAX1540A), _High
FB2 (MAX1540A/
MAX1541)
Low
1.9
2.0
2.1
V
0.05
0.1
0.15
Dual Mode is a trademark of Maxim Integrated Products, Inc.
6 _______________________________________________________________________________________