2A, Low-Voltage, Step-Down Regulator with
Synchronous Rectification and Internal Switches
ꢀBS LUTE%MꢀXIMUM%RꢀTINGS
V
, IN to GND ........................................................-0.3V to +6V
Continuous Power Dissipation (T = +ꢀ0°C)
A
CC
IN to V ............................................................................. 0.3V
GND to PGND..................................................................... 0.3V
SSOP (derate 16.ꢀmW/°C above +ꢀ0°C;
CC
part mounted on 1 in.2 of 1oz. copper)............................1.2W
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s) ................................ +300°C
All Other Pins to GND.................................-0.3V to (V
+ 0.3V)
CC
LX Current (Note 1)........................................................... 3.ꢀ5A
REF Short Circuit to GND Duration ............................Continuous
ESD Protection..................................................................... 2kV
Noue%±: LX has internal clamp diodes to PGND and IN. Applications that forward bias these diodes should take care not to exceed
the IC’s package power dissipation limits.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICꢀL%CHꢀRꢀCTERISTICS
(V = V
= +3.3V, FBSEL = GND, T =%0°C%uo%+85°C, unless otherwise noted. Typical values are at T = +25°C.)
IN
CC
ꢀ
A
PꢀRꢀMETER
SYMB L
C NDITI NS
MIN
TYP
MꢀX
UNITS
Input Voltage
V
, V
IN CC
3.0
5.5
V
V
= V
= 4V to 5.5V,
CC
IN
3.300
2.500
1.089
3.333
2.525
1.100
3.366
2.550
1.111
FBSEL = unconnected
I
= 0 to
LOAD
V
IN
= V
= 3V to 5.5V,
CC
CC
Preset Output Voltage
V
OUT
2A,
V
FBSEL = V
V
= V
OUT
FB
V
IN
= V
= 3V to 5.5V,
CC
FBSEL = REF
Adjustable Output Voltage
Range
V
= V
CC
= 3V to 5.5V,
IN
V
REF
V
V
IN
I
= 0, FBSEL = GND or REF
LOAD
FBSEL = GND
1
AC Load Regulation Error
DC Load Regulation Error
%
%
FBSEL = REF, V , or unconnected
CC
2
FBSEL = GND
0.2
0.4
FBSEL = REF, V , or unconnected
CC
Dropout Voltage
V
V
= V
= 3V, I
= 1A, FBSEL = V
CC
200
1.111
1
mV
V
DO
IN
CC
LOAD
Reference Voltage
V
1.089
1.100
0.5
REF
Reference Load Regulation
ΔV
I
I
= -1µA to +10µA
mV
REF
REF
V
IN
V
IN
V
IN
V
IN
= 4.5V
= 3V
ꢀ0
150
200
150
200
3.3
PMOS Switch
On-Resistance
R
= 0.5A
mΩ
mΩ
ON, P
LX
LX
100
ꢀ0
= 4.5V
= 3V
NMOS Switch
On-Resistance
R
I
= 0.5A
ON, N
100
2.9
Current-Limit Threshold
RMS LX Output Current
I
2.5
A
A
LIMIT
2.5
Idle Mode Current
Threshold
I
IM
0.25
0.45
0.65
A
Switching Frequency
f
(Note 2)
= 1.2V
350
360
3
kHz
µA
No-Load Supply Current
Shutdown Supply Current
I
+ I
V
FB
240
<1
IN
CC
I
µA
SHDN = GND
CC(SHDN)
PMOS Switch Off-Leakage
Current
I
15
µA
°C
SHDN = GND
IN
Thermal Shutdown
Threshold
T
Hysteresis = 15°C
150
SHDN
2
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
