MAX8758 Maxim Integrated Products, MAX8758 Datasheet - Page 8

• Manufacturer Part Number: MAX8758
• Description: Step-Up Regulator
• Manufacturer: Maxim Integrated Products

Step-Up Regulator with Switch Control
and Operational Amplifier for TFT LCD
(Circuit of Figure 1, V
8
HIGH-VOLTAGE SWITCH CONTROL FUNCTION
OP-AMP LARGE-SIGNAL STEP RESPONSE
_______________________________________________________________________________________
(MODE 2)
400µs/div
1µs/div
IN
= 3.3V, V
MAX8758 toc20
MAX8758 toc17
MAIN
V
V
V
V
2V/div
MODE
CTL
GON
= 8.5V, FREQ = SHDN = IN, T
OUTB
25
24
23
22
21
20
Typical Operating Characteristics (continued)
POSITIVE CHARGE-PUMP OUTPUT VOLTAGE
OP-AMP SMALL-SIGNAL STEP RESPONSE
0
vs. CHARGE-PUMP LOAD CURRENT
V
f
OSC
IN
CHARGE-PUMP LOAD CURRENT (mA)
= 3.3V
= 1.2MHz
5
200ns/div
10
A
= +25°C, unless otherwise noted.)
15
MAX8758 toc18
20
V
100mV/div
AC-COUPLED
V
200mV/div
AC-COUPLED
POSB
OUTB
-10
-5
-6
-7
-8
-9
NEGATIVE CHARGE-PUMP OUTPUT VOLTAGE
HIGH-VOLTAGE SWITCH CONTROL FUNCTION
0
V
f
OSC
IN
CHARGE-PUMP LOAD CURRENT (mA)
= 3.3V
= 1.2MHz
5
vs. LOAD CURRENT
(MODE 1)
400µs/div
10
15
MAX8758 toc19
20
V
V
V
MODE
CTL
GON