Max1747 triple charge-pump tft lcd dc-dc converter, Typical operating characteristics (continued) – Rainbow Electronics MAX1747 User Manual
Page 7
MAX1747
Triple Charge-Pump TFT LCD
DC-DC Converter
_______________________________________________________________________________________
7
4
10
22
16
28
34
3
7
5
9
11
13
MAXIMUM POSITIVE CHARGE-PUMP
OUTPUT VOLTAGE vs. SUPPLY VOLTAGE
MAX1747 toc13
V
SUPP
(V)
V
POS
(V)
I
POS
= 1mA
I
POS
= 10mA
V
POS(NOMINAL)
= 32V
LOAD TRANSIENT
MAX1747 toc14
40
µs/div
200mA
100mA
0
5.05V
4.95V
5V
V
IN
= 3.3V, V
OUT
= 5.0V
R
OUT
= 500
Ω TO 25Ω
C
INTG
= 1500pF
I
OUT
100mA/div
V
OUT
50mV/div
RIPPLE WAVEFORM
MAX1747 toc15
400ns/div
V
OUT
= +5.0V,I
OUT
= 200mA
V
NEG
= -7V, I
NEG
= 10mA
V
POS
= +12V, I
POS
= 5mA
V
OUT
20mV/div
V
NEG
10mV/div
V
POS
10mV/div
STARTUP WAVEFORM (NO LOAD)
MAX1747 toc16
1ms/div
2V
2V
0
4V
4V
0
2V
V
ON
2V/div
V
CXP
2V/div
V
OUT
2V/div
V
OUT
= 5V, NO LOAD
ON CONNECTED TO SHDN THROUGH
A 58k
Ω RESISTOR
STARTUP WAVEFORM (200mA LOAD)
MAX1747 toc17
1ms/div
2V
2V
0
4V
4V
0
2V
V
OUT
= 5V, R
OUT
= 25
Ω (200mA)
V
ON
2V/div
V
CXP
2V/div
V
OUT
2V/div
ON CONNECTED TO SHDN THROUGH
A 58k
Ω RESISTOR
POWER-UP SEQUENCE
MAX1747 toc18
ON CONNECTED TO SHDN THROUGH
A 58k
Ω RESISTOR
2V
0
0
5V
-10V
0
10V
2ms/div
V
MAIN
= 5V, V
NEG
= -7V, V
POS
= 12V
V
ON
2V/div
V
MAIN
5V/div
V
POS
10V/div
V
NEG
10V/div
Typical Operating Characteristics (continued)
(Circuit of Figure 1, V
IN
= V
SUPM
= +3.3V, T
A
= +25°C, unless otherwise noted.)