Micrel, Inc.
MIC2940A/2941A
Typical Applications
V
IN
+VIN
+V
IN
V
OUT
+
VIN
VOUT
V OUT
1.2V
26V
V
OUT
= 5V
S HUTDOWN
INPUT
ON
10µF
SHUTDOWN
GND
AD JU S T
OFF
R1 100
pF
22µF
GND
R1
V OUT = V R E F x (1 +
)
R2
1.23V
VREF
R2
Figure 2. MIC2940A-5.0 Fixed +5V Regulator
Figure 3. MIC2941A Adjustable Regulator
+V IN
+5V to +7V
V IN
VOUT
+V IN
V CC OUT
VOUT
V OUT = V IN
SHUTDOWN
INPUT
OFF
ON
SHUTDOWN
+
100pF
GND
ADJ
300k
1%
10µF
GND
ADJUST
3.3V
5V
470 k
220k
1%
2N2222
180k
1%
* Minimum Input-Output Voltage Ranges from 40mV to 400mV,
depending on Load Current.
Adjust Pin Low = Enable Output. Q1 ON = 3.3V, Q1 OFF = 5.0V.
Figure 4. MIC2941A Wide Input Voltage Range
Current Limit
Figure 5. MIC2941A 5.0V or 3.3V Selectable Regulator
with Shutdown
July 2007
8
M9999-071307
MICREL [ MICREL SEMICONDUCTOR ]
