Rainbow Electronics MAX1747 - Manual (Page 6)

MAX1747
Triple Charge-Pump TFT LCD
DC-DC Converter
6 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(Circuit of Figure 1, V IN = V SUPM = +3.3V, T A = +25°C, unless otherwise noted.)
0
2
4
6
8
10
12
14
16
0 0.5 1.0 1.5 2.0
NO-LOAD SUPPLY CURRENT
vs. SWITCHING FREQUENCY
MAX1747 toc04
FREQUENCY (MHz)
I CC
+ I
IN
(mA)
0
0.4
1.2
0.8
1.6
2.0
0 20 10 30 40 50
SWITCHING FREQUENCY
vs. I SHDN
MAX1747 toc05
I SHDN (mA)
FREQUENCY (MHz)
9.0
10.0
9.5
11.0
10.5
11.5
12.0
-40 10 -15 35 60 85
MAX1747 toc06
TEMPERATURE ( °C)
I IN
+ I
SUPM
(mA)
NO-LOAD SUPPLY CURRENT
vs. TEMPERATURE
V ON = 3.3V
R FREQ = 120k Ω
0.85
0.95
0.90
1.05
1.00
1.10
1.15
-40 10 -15 35 60 85
MAX1747 toc07
TEMPERATURE ( °C)
FREQUENCY (MHz)
SWITCHING FREQUENCY
vs. TEMPERATURE
V ON = 3.3V
R
FREQ
= 120k Ω
20
30
40
50
60
70
80
90
100
0 10 20 30 40
NEGATIVE LOW-POWER CHARGE-PUMP
EFFICIENCY vs. LOAD CURRENT
MAX1747 toc08
I NEG (mA)
EFFICIENCY (%)
V
SUPN
= 6V
V SUPN = 5V
V
SUPN
= 7V
V NEG = -7V
-7.1
-7.0
-6.9
-6.8
-6.7
-6.6
-6.5
-6.4
-6.3
0 10 20 30 40
NEGATIVE LOW-POWER CHARGE-PUMP
OUTPUT VOLTAGE vs. LOAD CURRENT
MAX1747 toc09
I
NEG
(mA)
V
NEG
(V)
V SUPN = 5V
V SUPN = 6V
V SUPN = 7V
-22
-18
-10
-14
-6
-2
3 7 5 9 11 13
MAXIMUM NEGATIVE CHARGE-PUMP
OUTPUT VOLTAGE vs. SUPPLY VOLTAGE
MAX1747 toc10
V SUPN (V)
V
NEG
(V)
I NEG = 10mA
I
NEG
= 1mA
V NEG(NOMINAL) = -20V
11.4
11.5
11.6
11.7
11.8
11.9
12.0
12.1
12.2
0 10 20 30 40
POSITIVE LOW-POWER CHARGE-PUMP
OUTPUT VOLTAGE vs. LOAD CURRENT
MAX1747 toc12
I POS (mA)
V
POS
(V)
V
SUPP
= 7V
V SUPP = 6V
V SUPP = 5V
20
30
40
50
60
70
80
90
100
0 10 20 30 40
POSITIVE LOW-POWER CHARGE-PUMP
EFFICIENCY vs. LOAD CURRENT
MAX1747 toc11
I POS (mA)
EFFICIENCY (%) V SUPP = 6V
V SUPP = 5V
V POS = 12V
V SUPP = 7V