Datasheet

MAX1830/MAX1831
3A, 1MHz, Low-Voltage, Step-Down Regulators with
Synchronous Rectification and Internal Switches
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= V
CC
= +3.3V, FBSEL = GND, T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.)
ELECTRICAL CHARACTERISTICS
(V
IN
= V
CC
= +3.3V, FBSEL = GND, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 5)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Input Voltage V
IN
, V
CC
3.0 5.5 V
FBSEL = V
CC
2.475 2.575
FBSEL =
unconnected
1.485 1.545
FBSEL = REF
(MAX1830)
1.782 1.854
V
IN
= +3V to +5.5V,
I
LOAD
= 0 to 3A,
V
FB
= V
OUT
FBSEL = GND 1.078 1.122
Preset Output Voltage V
OUT
V
IN
= +3.7V to +5.5V,
I
LOAD
= 0 to 3A,
V
FB
= V
OUT
FBSEL = REF
(MAX1831)
3.267 3.399
V
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SHDN = GND, into V
CC
and IN pins; LX = 0
or 3.3V
0.2 20
SHDN = GND, into IN with LX = 0 0.2 20
Shutdown Supply Current
SHDN = GND, into IN with LX = 3.3V 0.1 20
µA
Thermal Shutdown Threshold T
SHDN
Hysteresis = 15°C 165 °C
Undervoltage Lockout Threshold V
UVLO
V
IN
falling, hysteresis = 90mV 1.8 2.6 2.8 V
FB Input Bias Current I
FB
V
FB
= 1.2V 0 70 300 nA
R
TOFF
= 110kΩ 0.85 1.00 1.15 µs
R
TOFF
= 44kΩ 0.3 0.4 0.5 µsOff-Time t
OFF
R
TOFF
= 440kΩ 3.0 3.9 5.0 µs
Startup Off-Time 4
✕
t
OFF
µs
Minimum On-Time t
ON
(Note 2) 0.40 µs
Soft-Start Time (Note 3) 3
✕
256 cycles
SHDN Input Current I
SHDN
SHDN = 0 or V
CC
-0.5 0.5 µA
SHDN Logic Input Low Voltage V
IL
0.8 V
SHDN Logic Input High Voltage V
IH
2.0 V
FBSEL Input Current -5 5 µA
FBSEL = GND 0.2 V
FBSEL = REF 0.9 1.3 V
FBSEL = unconnected
0.7
✕
V
CC
- 0.2
0.7
✕
V
CC
+ 0.2
V
FBSEL Logic Thresholds
FBSEL = V
CC
V
CC
- 0.2 V
CC
+ 0.2 V