3.3V/5V or Adjustable-Output,
Step-Up DC-DC Converters
MAX856–MAX859
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (OUT to GND) ...................................-0.3V, +7V
Switch Voltage (LX to GND) .......................................-0.3V, +7V
— —
— –
SHDN , LBO to GND ....................................................-0.3V, +7V
–
–
LBI, REF, 3/ 5, FB to GND .........................-0.3V, (V
OUT
+ 0.3V)
Reference Current (I
REF
) ..................................................2.5mA
Continuous Power Dissipation (T
A
= +70°C)
SO (derate 5.88mW/°C above +70°C) .........................471mW
µMAX (derate 4.1mW/°C above +70°C) ......................330mW
CERDIP (derate 8.00mW/°C above +70°C) .................640mW
Reverse Battery Current (T
A
≤
+45°C, Note 1) .................750mA
Operating Temperature Ranges
MAX85_C_ _ ......................................................0°C to +70°C
MAX85_E_ _ ....................................................-40°C to +85°C
MAX85_MJA .................................................-55°C to +125°C
Junction Temperature .....................................................+150°C
Storage Temperature Range ............................-65°C to +160°C
Lead Temperature (soldering, 10sec) ............................+300°C
Note 1:
Reverse battery current is measured from the
Typical Operating Circuit’s
battery input terminal to GND when the battery is
connected backwards. A reverse current of 750mA will not exceed the SO or CERDIP package dissipation limits but, if left
for an extended time (more than ten minutes), may degrade performance.
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
(Circuits of Figure 2, V
IN
= 2.5V, I
LOAD
= 0mA, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
CONDITIONS
–
–
MAX856, 3/ 5 = 0V, 0mA
≤
I
LOAD
≤
100mA
–
–
MAX856, 3/ 5 = 3V, 0mA
≤
I
LOAD
≤
150mA
2V
≤
V
IN
≤
3V
MAX857, V
OUT
= 5V, 0mA
≤
I
LOAD
≤100mA
–
–
MAX858, 3/ 5 = 0V, 0mA
≤
I
LOAD
≤
25mA
–
–
MAX858, 3/ 5 = 3V, 0mA
≤
I
LOAD
≤
35mA
MAX859, V
OUT
= 5V, 0mA
≤
I
LOAD
≤
25mA
Minimum Start-Up
Supply Voltage
Minimum Operating Voltage
Quiescent Supply Current in
3.3V Mode (Note 2)
No Load Battery Current
Shutdown Quiescent Current
(Note 2)
Peak Inductor Current Limit
Reference Voltage
–
–
I
LOAD
= 0mA, 3/ 5 = 3V, LBI = 1.5V, V
OUT
= 3.47V,
(FB = 1.5V, MAX857/MAX859 only)
Output set for 3.3V, measured at V
IN
in Figure 2, R3 omitted.
— —
— –
–
–
SHDN = 0V, 3/ 5 = 3V, LBI = 1.5V, V
OUT
= 3.47V,
(FB = 1.5V, MAX857/MAX859 only)
MAX856/MAX857
MAX858/MAX859
1.23
MAX85_C
MAX85_E/M
1
500
125
1.25
0.8
1.22
1.25
25
I
SINK
= 2mA
LBO = 5V
0.4
1
1.27
2.0
1.28
I
LOAD
= 0mA
MIN
4.80
3.17
4.80
4.80
3.17
4.80
TYP
5.0
3.3
5.0
5.0
3.3
5.0
0.8
0.8
25
60
MAX UNITS
5.20
3.43
5.20
5.20
3.43
5.20
1.8
V
V
µA
V
Output Voltage
60
1
5
µA
µA
mA
V
%
V
mV
V
µA
No REF load
–
–
Reference-Voltage Regulation 3/ 5 = 3V, -20µA
≤
REF load
≤
250µA, C
REF
= 0.22µF
LBI Input Threshold
LBI Input Hysteresis
LBO Output Voltage Low
LBO Output Leakage Current
With falling edge
2
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
