Low-Noise Step-Up DC-DC Converters
ABSOLUTE MAXIMUM RATINGS
LX to GND ..............................................................-0.3V to +14V
Operating Temperature Range
IN, SHDN, FREQ, FB to GND ................................-0.3V to +6.2V
MAX1790EUA/MAX8715EUA ........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
SS, COMP to GND.......................................-0.3V to (V + 0.3V)
IN
RMS LX Pin Current ..............................................................1.2A
Continuous Power Dissipation (T = +70°C)
A
8-Pin µMAX (derate 4.1mW/°C above +70°C).............330mW
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 = SHDN = 3V, FREQ = GND, T = 0°C to +85°C, unless otherwise noted. Typical values are at T = +25°C.)
IN
A
A
PARAMETER
Input Supply Range
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
2.6
5.5
V
IN
V
rising, typical hysteresis is 40mV,
IN
V
Undervoltage Lockout
UVLO
2.25
2.38
2.52
V
IN
LX remains off below this level
V
V
V
V
= 1.3V, not switching
= 1.0V, switching
0.18
2
0.35
5
FB
FB
FB
FB
MAX1790
Quiescent Current
I
I
mA
µA
IN
IN
= 1.3V, not switching
= 1.0V, switching
0.21
2.5
0.1
0.35
5.0
10
MAX8715
Shutdown Supply Current
ERROR AMPLIFIER
Feedback Voltage
SHDN = GND
V
Level to produce V
= 1.24V
COMP
1.222
1.24
0
1.258
40
V
FB
MAX1790
MAX8715
FB Input Bias Current
I
V
= 1.24V
nA
FB
FB
125
190
Feedback-Voltage Line
Regulation
Level to produce V
2.6V < V < 5.5V
IN
= 1.24V,
COMP
0.05
0.15
%/V
MAX1790
MAX8715
70
70
140
160
700
240
240
Transconductance
g
ΔI = 5µA
µS
m
Voltage Gain
A
V/V
V
OSCILLATOR
FREQ = GND
540
1000
79
640
1220
85
740
1500
92
Frequency
f
kHz
%
OSC
DC
FREQ = IN
FREQ = GND
Maximum Duty Cycle
FREQ = IN
84
N-CHANNEL SWITCH
V
= 1V,
MAX1790
MAX8715
1.2
1.8
1.6
2.4
2.3
3.4
FB
Current Limit
I
duty cycle =
65% (Note 1)
A
LIM
MAX1790
MAX8715
0.21
0.15
0.01
5
0.5
0.35
20
On-Resistance
R
Ω
ON
MAX1790
MAX8715
Leakage Current
I
V
= 12V
LX
µA
LXOFF
30
2
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
