MAX1623 Datasheet, PDF (2/12 Pages) Maxim Integrated Products – 3A, Low-Voltage, Step-Down Regulator with Synchronous Rectification and Internal Switches

3A, Low-Voltage, Step-Down Regulator with
Synchronous Rectification and Internal Switches
ABSOLUTE MAXIMUM RATINGS
IN to PGND .....................................................................0V to 6V
V_CC to GND ................................................................-0.3V to 6V
PGND to GND.....................................................................±0.5V
IN to V_CC.............................................................................±0.5V
LX to PGND.................................................................-0.5V to 6V
SHDN to GND .............................................................-0.3V to 6V
REF, FBSEL, COMP, FB, TOFF to GND .....-0.3V to (V_CC + 0.3V)
REF Short to GND ......................................................Continuous
Continuous Power Dissipation (T_A = +70°C) (with part mounted
on 1 sq. inch of one ounce copper)
20-Pin SSOP (derate 22mW/°C above +70°C) ................1.3W
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
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.
ELECTRICAL CHARACTERISTICS
(V_IN = V_CC = +5V, FBSEL unconnected, R_TOFF = 110kΩ, T_A = 0°C to +85°C, unless otherwise noted. Typical values are at T_A =
+25°C.)
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Input Voltage Range
4.5
5.5
V
Output Voltage
V_IN = 4.5V to 5.5V,
I_LOAD = 0 to 3A
FBSEL = unconnected
3.296 3.330 3.366
FBSEL = V_CC
2.49 2.525 2.550
V
FBSEL = GND or REF
1.089 1.100 1.110
Output Adjustment Range
Reference Output Voltage
Reference Load Regulation
Current-Limit Threshold
FBSEL = GND or REF (Note 1)
I_REF = 0
I_REF = -1µA to 10µA
V_REF
3.80
V
1.089 1.100 1.110
V
1
mV
3.65
4.65
A
PMOS Switch On-Resistance
NMOS Switch On-Resistance
Maximum Switching Frequency
Idle Mode Threshold (Note 2)
V_IN = 4.5V
V_IN = 4.5V
I_LOAD ≥ 1.5A (Note 1)
55
100
mΩ
60
100
mΩ
350 kHz
1
1.25
1.5
A
No-Load Supply Current
Shutdown Supply Current
Does not include switching losses
SHDN = GND
400
525
µA
0.5
10
µA
LX Leakage Current
Thermal Shutdown Threshold
V_IN = 5.5V, V_LX = 5.5V or 0
±20
µA
145
°C
Undervoltage Lockout Threshold
V_CC falling, 100mV hysteresis
4.1
4.2
4.3
V
FB Input Bias Current
FBSEL = GND, adjustable output mode, V_FB = 1.2V
-25
25
nA
Error-Amplifier Gain Bandwidth
(Note 1)
500
kHz
Off-Time Adjustment Range
0.5
4
µs
Off-Time Default Period
0.85 1.00 1.15
µs
AC Output Load Regulation
SHDN Input Current
SHDN Input Low Voltage
SHDN Input High Voltage
FBSEL = GND
FBSEL = REF
SHDN = GND or V_CC
1
%
2
-1
0.03
1
µA
0.8
V
2
V
2 _______________________________________________________________________________________