MIC2950/2951
Micrel
RIPPLE REJECTION (dB)
70
60
50
40
I
L
= 50
µA
VOLTAGE NOISE
SPECTRAL DENSITY (µV/
√
Hz)
80
3.5
3.0
2.5
2.0
1.5
1.0
0.5
PIN 2 TO PIN 4 RESISTANCE (k
Ω
)
Ripple Rejection
Output Noise
I
L
= 100 mA
C
L
= 4.7
µF
C
L
= 220
µF
C
L
=
3.3
µF
0.01
µF
BYPASS
PIN 1 TO
PIN 7
MIC2951 Divider Resistance
400
300
I
L
= 100 mA
200
C
L
= 1.5
µF
30 V
IN
= 6V
V
OUT
= 5V
20
10
10
1
10
2
10
3
10
4
10
5
10
6
100
0.0
10
2
10
3
10
4
10
5
0
-75 -50 -25 0 25 50 75 100 125 150
TEMPERATURE (°C)
FREQUENCY (Hz)
FREQUENCY (Hz)
SHUTDOWN THRESHOLD VOLTAGE (V)
1.8
1.6
1.4
1.2
1.0
0.8
0.6
-75 -50 -25 0 25 50 75 100 125 150
TEMPERATURE (°C)
OUTPUT VOLTAGE CHANGE (mV)
Shutdown Threshold Voltage
Line Regulation
OUTPUT CURRENT (mA)
30
25
20
15
T = 150°C
10
J
5
0
10
5 T
J
= 125°C
0
-5
-10
5
10
15
150
I
L
= 100
µA
I
L
= 1 mA
140
130
120
100
80
MIC2951 Maximum
Rated Output Current
8-PIN SOIC
SOLDERED
TO PC BOARD
T
J
MAX
= 125°C
V
OUT
= 5V
T
A
= 25°C
3
I
L
= 100
µA
60 T
A
= 50°C
40
T
A
= 85°C
20
0
0
5
10 15 20 25
INPUT VOLTAGE (V)
30
20
25
30
INPUT VOLTAGE (V)
POWER
OUTPUT VOLTAGE
DISSIPATION (W) CHANGE (mV)
150
OUTPUT CURRENT (mA)
140
130
120
100
80
60
40
20
0
MIC2950 Maximum
Rated Output
TO-92 PACKAGE
.25" LEADS SOLDERED
TO PC BOARD
Thermal Response
4
2
0
-2
1
0
-1
0
10
20
30
40
50
TIME (µS)
1.25W
OUTPUT CURRENT (mA)
5
600
500
400
300
200
100
Fold-Back Current Limiting
T
J
MAX
= 125°C
T
A
= 25°C
T = 85°C
0
5
10
15
20
25
A
30
0
1
2
3
4
5
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
February 1999
3-57
MICREL [ MICREL SEMICONDUCTOR ]
