MAX8571 MAXIM [Maxim Integrated Products], MAX8571 Datasheet - Page 4

• Manufacturer Part Number: MAX8571
• Description: High-Efficiency LCD Boost with True Shutdown
• Manufacturer: MAXIM [Maxim Integrated Products]

High-Efficiency LCD Boost
with True Shutdown
(MAX8571, V
4
100
700
600
500
400
300
200
100
_______________________________________________________________________________________
90
80
70
60
50
40
0
2.7
0
L1 = MURATA LQH32CN220K23
EFFICIENCY vs. BATTERY VOLTAGE
PEAK INDUCTOR CURRENT LIMIT
3.1
CC
2
V
MAX8574
5mA LOAD
CC
vs. SUPPLY VOLTAGE
= 3.6V, V
3.5
V
BATTERY VOLTAGE (V)
SUPPLY VOLTAGE (V)
= 3.6V
V
OUT
CC
4
MAX8571
(FIGURE 4)
1mA LOAD
3.9
LINE TRANSIENT 3V TO 5.5V (MAX8571)
3.6kΩ LOAD, R1 = 3.9MΩ, R2 = 287kΩ
6
MAX8570
OUT
4.3
8
= 18V, Circuit of Figure 2, T
4.7
10
100µs/div
5.1
5.5
12
MAX8570/71/73/74/75 toc13
100
120
100
Typical Operating Characteristics (continued)
90
80
70
60
50
40
80
60
40
20
0
0.1
0
SUPPLY CURRENT vs. LOAD CURRENT
MAX8574, TOKO A914BYW-220M
EFFICIENCY vs. LOAD CURRENT
200mV/div
(AC-COUPLED)
2V/div
0
MAX8570, MURATA LQH32CN220K23
A
= +25°C, unless otherwise noted.)
WITH 22µH INDUCTOR
MAX8571, MURATA LQH32CN220K23
LOAD CURRENT (mA)
LOAD CURRENT (mA)
1
5
L1 = MURATA LQH32CN220K23
10
10
V
V
OUT
CC
3kΩ LOAD
100
15
LINE TRANSIENT 3V TO 5.5V
(FIGURE 3, MAX8573)
100
80
70
60
50
40
30
20
10
90
80
70
60
50
40
0
100µs/div
NO-LOAD CURRENT vs. SUPPLY VOLTAGE
0.1
0
MAX8570, L1 = MURATA LQH32CN470K23
L1 = MURATA
LQH32CN220K23
MAX8571, L1 = TOKO A914BYW-470M
R1 = 7.87MΩ
R2 = 576kΩ
EFFICIENCY vs. LOAD CURRENT
MAX8573,
FIGURE 3
1
MAX8570/71/73/74/75 toc14
WITH 47µH INDUCTOR
SUPPLY VOLTAGE (V)
LOAD CURRENT (mA)
2
1
3
200mV/div
(AC-COUPLED)
2V/div
0
NO SWITCHING
10
4
R1 = 3.9MΩ
R2 = 287kΩ
5
100
6