ML4823
ERROR AMPLIFIER
The ML4823 error amplifier is a 5.5MHz bandwidth 12V/µs
slew rate op-amp with provision for limiting the positive
output voltage swing (Output Inhibit line) for ease in
implementing the soft start function.
100
80
60
GAIN
5
40
4
V
IN
(V)
3
V
OUT
2
20
0
φ
–20
0
0
–90
1
0
0.2
0.4
0.6
TIME (µs)
0.8
1.0
100
1K
10K
100K
1M
FREQ (Hz)
–180
10M 100M
Figure 5. Unity Gain Slew Rate
OUTPUT DRIVER STAGE
The ML4823 Output Driver is a 2A peak output high speed
totem pole circuit designed to quickly switch the gates of
capacitive loads, such as power MOSFET transistors.
V
CC
POWER
V
C
Q2
OUT
T
OUT
(V)
Figure 6. Open Loop Frequency Response
0.2
I
L
(A)
0
15
–0.2
10
Q1
POWER
GND
5
0
0
40
80
120
TIME (ns)
160
200
Figure 7. Simplified Schematic
3
Figure 9. Rise/Fall Time (C
L
= 1000pF)
2
I
L
(A)
0
2
V
SAT
(V)
T
OUT
(V)
SOURCE
15
–2
10
1
5
SINK
0
0
0
0.5
I
OUT
(A)
1.0
1.5
0
100
200
300
TIME (ns)
400
500
Figure 8. Saturation Curves
Figure 10 Rise/Fall Time (C
L
= 10,000pF)
6