Electrical characteristics – Rainbow Electronics MAX1845 User Manual
Page 5
MAX1845
Dual, High-Efficiency, Step-Down
Controller with Accurate Current Limit
_______________________________________________________________________________________
5
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, V
DD
= V
CC
= 5V, SKIP = GND, V+ = 15V, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
PWM CONTROLLERS
V+
Battery voltage, V+
2
28
Input Voltage Range
V
CC
/V
DD
V
CC
, V
DD
4.5
5.5
V
FB1 to GND
1.773
1.827
FB1 to V
CC
1.477
1.523
D C O utp ut V ol tag e, O U T1 ( N ote 2)
V
OUT1
V+ = 2V to 28V, SKIP = V
CC
,
I
LOAD
= 0 to 10A
FB1 to OUT1
0.985
1.015
V
FB2 to GND
2.463
2.537
D C O utp ut V ol tag e, O U T2 ( N ote 2)
V
OUT2
V+ = 2V to 28V, SKIP = V
CC
,
I
LOAD
= 0 to 10A
FB2 to OUT2
0.985
1.015
V
Output Voltage Adjust Range
OUT1, OUT2
1
5.5
V
Dual-Mode Threshold (Low)
OVP, FB_
0.05
0.15
V
OVP, ILIM_
V
CC
-
1.5
V
CC
-
0.4
Dual-Mode Threshold (High)
FB_
1.9
2.1
V
R
OUT1
V
OUT1
= 1.5V
75
OUT_ Input Resistance
R
OUT2
V
OUT2
= 2.5V
100
k
Ω
FB_ Input Bias Current
I
FB
-0.1
0.1
µA
TON = GND
120
153
TON = REF
153
195
TON = float
217
272
On-Time, Side 1 (Note 3)
t
ON1
V+ = 24V, V
OUT1
= 2V
TON = V
CC
308
390
ns
TON = GND
160
204
TON = REF
205
263
TON = float
295
371
On-Time, Side 2 (Note 3)
t
ON2
V+ = 24V, V
OUT2
= 2V
TON = V
CC
422
534
ns
TON = GND
125
145
TON = REF
125
145
TON = float
125
145
On-Time Tracking (Note 3)
On-time 2, with
respect to on-time 1
TON = V
CC
125
145
%
Minimum Off-Time (Note 3)
t
OFF
500
ns
Quiescent Supply Current (V
CC
)
I
CC
FB forced above the regulation point
1500
µA
Quiescent Supply Current (V
DD
)
I
DD
FB forced above the regulation point
5
µA
Quiescent Supply Current (V+)
I+
Measured at V+
70
µA
Reference Voltage
V
REF
V
CC
= 4.5V to 5.5V, no external REF load
1.98
2.02
V
Reference Load Regulation
I
REF
= 0 to 50uA
0.01
V
Overvoltage Trip Threshold
(Fixed-Threshold Mode)
OVP = GND, with respect to FB_ regulation
point, no load
112
117
%
Output Undervoltage Threshold
UVP = V
CC
, with respect to FB_ regulation
point, no load
65
75
%
Current-Limit Threshold (Fixed)
GND - V
CS
, ILIM_ = V
CC
35
65
mV