Electrical characteristics (continued) – Rainbow Electronics MAX1543 User Manual
Page 3
MAX1542/MAX1543
TFT LCD DC-to-DC Converter with
Operational Amplifiers
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= 3V, V
SUP
= 8V, V
SRC
= 28V, FREQ = IN (MAX1543), PGND = AGND = 0, T
A
= 0°C to +85°C, typical values at T
A
= +25°C,
unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
FB Input Bias Current
V
FB
= 1.5V
-40
+40
nA
FB Transconductance
∆I
COMP
= 5µA
75
160
280
µS
FB Voltage Gain
FB to COMP
700
V/V
LX On-Resistance
R
LX(ON)
210
400
m
Ω
LX Leakage Current
I
LX
V
LX
= 13V
0.01
20
µA
LX Current Limit
I
LIM
V
FB
= 1V, duty cycle = 65%
1.2
1.5
1.8
A
Current-Sense Transresistance
0.30
0.50
0.65
Ω
MAX1542
14
FREQ = AGND
13
Soft-Start Period
t
SS
MAX1543
FREQ = IN
14
ms
Soft-Start Step Size
I
LIM
/ 8
A
OPERATIONAL AMPLIFIERS
SUP Supply Range
V
SUP
4.5
13.0
V
SUP Supply Current
I
SUP
Buffer configuration, V
POS_
= 4V, no load
1.3
1.9
mA
Input Offset Voltage
V
OS
V
CM
= V
SUP
/2, T
A
= +25°C
0
12
mV
Input Bias Current
I
BIAS
NEG1, NEG2, POS1, POS2
+1
±50
nA
Input Common-Mode Voltage
Range
V
CM
0
V
SUP
V
Common-Mode Rejection Ratio
CMRR
0
≤ V
NEG_
, V
POS_
≤ V
SUP
50
90
dB
Open-Loop Gain
125
dB
I
OUT_
= 100µA
V
SUP
-
15
V
SUP
-
2
Output Voltage Swing High
V
OH
I
OUT_
= 5mA
V
SUP
-
150
V
SUP
-
80
mV
I
OUT_
= -100µA
2
15
Output Voltage Swing Low
V
OL
I
OUT_
= -5mA
80
150
mV
Source
50
150
Short-Circuit Current
To V
SUP
/2
Sink
50
140
mA
Output Source-and-Sink Current
Buffer configuration, V
POS_
= 4V,
|
∆V
OS|
< 10mV
40
mA
Power-Supply Rejection Ratio
PSRR
DC, 6V
≤ V
SUP
≤ 13V, V
NEG_
, V
POS_
=
V
SUP
/2
60
100
dB
Slew Rate
7.5
V/µs
-3dB Bandwidth
R
L
= 10k
Ω, C
L
=10pF, buffer configuration
12
MHz
Gain-Bandwidth Product
GBW
Buffer configuration
8
MHz
POSITIVE GATE-DRIVER TIMING AND CONTROL SWITCHES
DEL Capacitor Charge Current
During startup, V
DEL
= 1V
4
5
6
µA