contact-fact Micrel Semiconductor, contact-fact Datasheet - Page 14

• Manufacturer Part Number: contact-fact
• Description: Mic2950/mic2951 150ma Low-dropout Voltage Regulator
• Manufacturer: Micrel Semiconductor

Schematic Diagram
MIC2950/2951
MIC2950/2951
For values shown, Regulator shuts down when V
* Sets disconnect voltage
** Sets disconnect hysteresis
LM34 for 125°F Shutdown
LM35 for 125°C Shutdown
AUX. SHUTDOWN
ON
FOR 5.5V
≈ 400kΩ*
+
S E N S O R
T EM P.
6V
S E A L E D
LEAD-
ACID
B A T T E R Y
S O U R C E
50 k Ω
10 k Ω
Q42
INPUT
Q40
R30
LM34 OR
k Ω
Q6
30
O F F
LM35
50kΩ
20 k Ω
Q41
R2
R1
10
Q1
Q3
–
+
120kΩ
F B
3
50kΩ
R3
R11
18
k Ω
E R R O R
S D
180
IN
R5
kΩ
System Overtemperature Protection Circuit
GND
C1
20
pF
Q13
13kΩ
LM385
MIC2951
R4
140
R6
kΩ
4
+V IN
Q4
+V IN
Q38
Q12
–
Q39
1.5kΩ**
100kΩ
Q2
IN
8
Q5
Q37
31.4 k Ω
27.8kΩ
E R R O R
R11
20.6
< 5.5 V and turns on again at 6.0 V. Current drain in disconnected mode is 150µA.
F B
R8
R9
Q15A
kΩ
Low-Battery Disconnect
V
R26
60 k Ω
7
OUT
8.2kΩ
Q7
Q11
Q36
R10
150
k Ω
1N457
Q8
5
1
R25
2.8 k Ω
3
Q9
Q34
10kΩ
S D
5° PRE-SHUTDO WN FL AG
14
R12
110
kΩ
Q20
O V E R T E M P E R A T U R E
( V+ GOES OFF W HEN
E X T E R N A L C I R C U I T
P R O T E C T E D F R O M
MIC2951
Q18
Q16
R13
100
GND
k Ω
+V IN
TEMP.> 125
GND
R22
150kΩ
Q15B
8
4
Q17
S E N S E
R14
350
k Ω
C2
40 pF
V
OUT
Q30
Q19
DENOTES CONNECTION ON MIC2950 ONLY
Q14
Q31
°)
Q21
F E E D B A C K
12kΩ
Q29
R17
1
2
R24
50kΩ
1µF
Q28
O R
Q22
R15
100kΩ
R16
30 k Ω
Q25
R23 60k Ω
+
R21 8Ω
R18
20kΩ
Q26
10Ω
R17
R E L A Y
100 x
Q23
SHDN
+
R27
182kΩ
R28
60kΩ
Q24
MAIN V+
MEMORY V+
5V TAP
SEN SE
OUT
20Ω
NI-CAD
B A C K U P
B A T T E R Y
Micrel, Inc.
July 2005