Typical operating characteristics (continued) – Rainbow Electronics MAX1543 User Manual
Page 8
MAX1542/MAX1543
TFT LCD DC-to-DC Converter with
Operational Amplifiers
8
_______________________________________________________________________________________
Typical Operating Characteristics (continued)
(V
IN
= 3.3V, V
MAIN
= 8V, f
OSC
= 1.2MHz, T
A
= +25°C, unless otherwise noted.)
STEP-UP REGULATOR
PULSED LOAD-TRANSIENT RESPONSE
MAX1542 toc16
10
µs/div
I
MAIN
1A/div
I
L
500mA/div
V
MAIN
100mV/div
AC-COUPLED
L = 4.7
µH
R
COMP
= 120k
Ω
C
COMP
= 470pF
STARTUP SEQUENCE
MAX1542 toc17
1ms/div
V
IN
2V/div
V
MAIN
8V/div
V
GOFF
5V/div
V
COM
10V/div
HEAVY-LOAD
SOFT-START WAVEFORMS
MAX1542 toc18
2ms/div
R
LOAD
= 10
Ω
V
IN
5V/div
V
MAIN
5V/div
I
L
500mA/div
TIMER DELAY LATCH
RESPONSE TO OVERLOAD
MAX1542 toc19
10ms/div
I
L
2A/div
V
MAIN
5V/div
V
OUT1
5V/div
V
COM
20V/div
OPERATIONAL AMPLIFIER
RAIL-TO-RAIL I/O PERFORMANCE
MAX1542 toc20
100
µs/div
V
POS1
5V/div
V
OUT1
5V/div
V
SUP
= 8V
BUFFER CONFIGURATION
OPERATIONAL AMPLIFIER
LOAD-TRANSIENT RESPONSE
MAX1542 toc21
1
µs/div
V
OUT1
1V/div
AC-COUPLED
4V
+50
0
-50
I
OUT1
50mA/div
BUFFER CONFIGURATION
OPERATIONAL AMPLIFIER
LARGE-SIGNAL STEP RESPONSE
MAX1542 toc22
1
µs/div
V
POS1
500mV/div
AC-COUPLED
4V
V
OUT1
2V/div
V
SUP
= 8V
A
V
= 10