MAX1678 Datasheet, PDF (5/12 Pages) Maxim Integrated Products – 1-Cell to 2-Cell, Low-Noise, High-Efficiency, Step-Up DC-DC Converter

1-Cell to 2-Cell, Low-Noise,
High-Efficiency, Step-Up DC-DC Converter
Typical Operating Characteristics (continued)
(Circuit of Figure 7 (Fixed Mode, 3.3V) or Figure 8 (Adjustable Mode), T_A = +25°C, unless otherwise noted.)
EFFICIENCY WITH DIFFERENT INDUCTORS
90
V_BATT = 1.2V
85
V_OUT = 3.3V
I_LOAD = 20mA
80
75
70
65
60
55
50
COILCRAFT SUMIDA MURATA TDK
NO-LOAD BATTERY CURRENT
vs. INPUT VOLTAGE
1000
V_OUT = 5.0V
R1 = 3MΩ, R2 = 1MΩ
V_OUT = 3.0V
FB = GND
100
V_OUT = 2.4V
R1 = 1MΩ, R2 = 1MΩ
L1 = 47µH
SUMIDA CD43-470
10
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE (V)
BATT AND OUT QUIESCENT CURRENT
vs. TEMPERATURE
45
40
V_BATT = 1.3V
V_OUT = 3.6V
35 ^{FB = GND}
I_OUT
30
25
20
15
10
I_BATT
5
0
-40 -20
0 20 40 60
TEMPERATURE (°C)
80 100
SHUTDOWN BATTERY CURRENT
vs. INPUT VOLTAGE
12
3.3V FIXED MODE
10 ^{L1 = 47µH}
SUMIDA CD43-470
8
6
4
2
ON-TIME CONSTANT (K)
vs. TEMPERATURE
9.0
V_BATT = 1.3V
8.8
8.6
8.4
8.2
8.0
7.8
MINIMUM START-UP INPUT VOLTAGE
vs. LOAD CURRENT
1.3
L1 = 47µH
1.2 SUMIDA CD43-470
3.3V FIXED MODE
1.1
WITHOUT
DIODE
1.0
0.9
WITH EXTERNAL
SCHOTTKY DIODE
0.8
(FIGURE 3)
0.7
0
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
7.6
-40 -20
0 20 40 60
TEMPERATURE (°C)
80 100
0.6
0
5 10 15 20 25 30 35
LOAD CURRENT (mA)
MAXIMUM LOAD CURRENT
vs. INPUT VOLTAGE
(L1 = 22µH)
140
L1 = 22µH
120 SUMIDA CD43-220
MAXIMUM LOAD CURRENT
vs. INPUT VOLTAGE
(L1 = SUMIDA 47µH)
140
L1 = 47µH
120 SUMIDA CD43-470
MAXIMUM LOAD CURRENT
vs. INPUT VOLTAGE
(L1 = TDK 47µH)
140
L1 = 47µH
120 TDK NLC453232T-470K
100
V_OUT = 2.4V
80
100
V_OUT = 3.3V
80
100
80
V_OUT = 3.3V
60
40
V_OUT = 3.3V
20
V_OUT = 5.0V
60 V_OUT = 2.4V
40
20
V_OUT = 5.0V
60
V_OUT = 2.4V
40
20
V_OUT = 5.0V
0
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE (V)
0
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE (V)
0
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE (V)
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