Electrical characteristics (continued) – Rainbow Electronics MAX1842 User Manual
Page 3
MAX1742/MAX1842
1A/2.7A, 1MHz, 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.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX1742
1.3
1.5
1.7
Current-Limit Threshold
I
LIMIT
MAX1842
3.1
3.6
4.1
A
RMS LX Output Current
3.1
A
MAX1742
0.1
0.3
0.5
Idle Mode Current Threshold
I
IM
MAX1842
0.3
0.6
0.9
A
Switching Frequency
f
(Note 2)
1
MHz
No-Load Supply Current
I
IN
+ I
CC
V
FB
= 1.2V
350
600
µA
Shutdown Supply Current
I
CC
(SHDN)
SHDN = GND
<1
5
µA
PMOS Switch Off-Leakage
Current
I
IN
SHDN = GND
15
µA
Thermal Shutdown Threshold
T
SHDN
Hysteresis = 15°C
160
°C
Undervoltage Lockout Threshold
V
UVLO
V
IN
falling, hysteresis = 90mV
2.5
2.6
2.7
V
FB Input Bias Current
I
FB
V
FB
= 1.2V
0
60
250
nA
R
TOFF
= 110k
Ω
0.9
1.00
1.1
R
TOFF
= 30.1k
Ω
0.24
0.30
0.37
Off-Time Default Period
t
OFF
R
TOFF
= 499k
Ω
3.8
4.5
5.2
µs
Off-Time Startup Period
t
OFF
FB = GND
4
✕
t
OFF
µs
On-Time Period
t
ON
(Note 2)
0.4
µs
SS Source Current
I
SS
4
5
6
µA
SS Sink Current
I
SS
V
SS
= 1V
100
µA
SHDN Input Current
I
SHDN
V
SHDN
= 0 to V
CC
-1
1
µA
SHDN Input Low Threshold
V
IL
0.8
V
SHDN Input High Threshold
V
IH
2.0
V
FBSEL Input Current
-4
+4
µA
FBSEL = GND
0.2
FBSEL = REF
0.9
1.3
FBSEL = unconnected
0.7
✕
VCC
- 0.2
0.7
✕
VCC
+0.2
FBSEL Logic Thresholds
FBSEL = V
CC
V
CC
- 0.2
V