Typical operating characteristics – Rainbow Electronics MAX1543 User Manual
Page 6
MAX1542/MAX1543
TFT LCD DC-to-DC Converter with
Operational Amplifiers
6
_______________________________________________________________________________________
Typical Operating Characteristics
(V
IN
= 3.3V, V
MAIN
= 8V, f
OSC
= 1.2MHz, T
A
= +25°C, unless otherwise noted.)
50
1
1000
100
STEP-UP REGULATOR EFFICIENCY
vs. LOAD CURRENT (V
MAIN
= 8V)
65
55
85
75
95
70
60
90
80
MAX1542 toc01
LOAD CURRENT (mA)
EFFICIENCY (%)
10
MAX1543
f
OSC
= 1.2MHz
L = 4.7
µH
V
IN
= 3.3V
V
IN
= 2.7V
V
IN
= 5V
50
1
1000
100
10
STEP-UP REGULATOR EFFICIENCY
vs. LOAD CURRENT (V
MAIN
= 8V)
65
55
85
75
95
70
60
90
80
MAX1542 toc02
LOAD CURRENT (mA)
EFFICIENCY (%)
MAX1543
f
OSC
= 640kHz
L = 10
µH
V
IN
= 3.3V
V
IN
= 2.7V
V
IN
= 5V
V
IN
= 5V
STEP-UP REGULATOR OUTPUT VOLTAGE
vs. LOAD CURRENT (V
MAIN
= 8V)
MAX1542 toc03
LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
10
100
7.6
7.7
7.8
7.9
8.0
8.1
7.5
1
1000
V
IN
= 3.3V
f
OSC
= 1.2MHz
MAX1542 toc04
V
IN
(V)
SUPPLY CURRENT (mA)
5.0
4.5
4.0
3.5
3.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0
2.5
5.5
STEP-UP REGULATOR SUPPLY CURRENT
vs. SUPPLY VOLTAGE
NO LOAD
f
OSC
= 1.2MHz
R
1
= 75k
Ω
R
2
= 13.7k
Ω
SUP DISCONNECTED
CURRENT INTO INDUCTOR
CURRENT INTO IN PIN
STEP-UP REGULATOR SUPPLY CURRENT
vs. TEMPERATURE
MAX1542 toc05
TEMPERATURE (
°C)
SUPPLY CURRENT (mA)
60
35
10
-15
0.4
0.8
1.2
1.6
2.0
0
-40
85
NO LOAD
V
IN
= 3.3V
f
OSC
= 1.2MHz
R
1
= 75k
Ω
R
2
= 13.7k
Ω
SUP DISCONNECTED
CURRENT INTO INDUCTOR
CURRENT INTO IN PIN
MAX1542 toc06
V
IN
(V)
SWITCHING FREQUENCY (kHz)
5.0
4.5
4.0
3.5
3.0
600
800
1000
1200
1400
400
2.5
5.5
SWITCHING FREQUENCY
vs. INPUT VOLTAGE
MAX1543
I
MAIN
= 200mA
FREQ = IN
FREQ = AGND
SUP SUPPLY CURRENT
vs. SUP VOLTAGE
MAX1542 toc07
V
SUP
(V)
I
SUP
(mA)
12.0
10.5
9.0
7.5
6.0
1.00
1.25
1.50
1.75
0.75
4.5
13.5
NO LOAD
BUFFER CONFIGURATION
POS_ = V
SUP
/2
SUP SUPPLY CURRENT
vs. TEMPERATURE
MAX1542 toc08
TEMPERATURE (
°C)
I
SUP
(mA)
60
35
10
-15
1.2
1.6
2.0
0.8
-40
85
NO LOAD
BUFFER CONFIGURATION
V
POS
= V
SUP
/2
V
SUP
= 13V
V
SUP
= 8V
V
SUP
= 5V