MIC2940A Datasheet, PDF (2/8 Pages) Micrel Semiconductor – 1.25A Low-Dropout Voltage Regulator Preliminary Information

MIC2940A/2941A
Ordering Information
Part Number
MIC2940A-3.3BT
MIC2940A-3.3BU
MIC2940A-5.0BT
MIC2940A-5.0BU
MIC2940A-12BT
MIC2940A-12BU
MIC2941ABT
MIC2941ABU
Voltage
3.3
3.3
5.0
5.0
12
12
Adj
Adj
Temperature Range*
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
Package
TO-220
TO-263
TO-220
TO-263
TO-220
TO-263
TO-220-5
TO-263-5
* Junction temperatures
Micrel
Absolute Maximum Ratings
If Military/Aerospace specified devices
are required, contact your local Micrel
representative/distributor for availability
and specifications.
Power Dissipation (Note 1) ............... Internally Limited
Lead Temperature (Soldering, 5 seconds) ........ 260°C
Storage Temperature Range ............ –65°C to +150°C
Operating Junction Temperature Range
................................................. –40°C to +125°C
TO-220 θ_JC ........................................................ 2 °C/W
TO-263 θ_JC ........................................................ 2 °C/W
Input Supply Voltage ............................... –20V to +60V
Operating Input Supply Voltage .................. 2V^† to 26V
Adjust Input Voltage (Notes 9 and 10)
...................................................... –1.5V to +26V
Shutdown Input Voltage ......................... –0.3V to +30V
Error Comparator Output Voltage .......... –0.3V to +30V
† _{Across the full operating temperature, the minimum}
input voltage range for full output current is 4.3V to 26V.
Output will remain in-regulation at lower output voltages
and low current loads down to an input of 2V at 25°C.
Schematic Diagram
IN
FEEDBACK
Q15A
Q3
Q6
Q1
10
R1
Q42
20 kΩ
R2
50 kΩ
Q40
Q41
R11
18
kΩ
C1
20
pF
Q4
Q7
Q5
R11
20.6
kΩ
Q2
Q9
Q8
Q20
R8 ^R10
31.4 kΩ
150
kΩ
R5
R6
R9
180
140
27.8 kΩ
kΩ
kΩ
R12
110
Q13
Q12
kΩ
Q11
R30
30
kΩ
R3
R4
50 kΩ
13 kΩ
50 kΩ
10 kΩ
ERROR
Q37
Q36
Q38
R26
60 kΩ
Q39
Q34
R25
2.8 kΩ
Q15B
Q16 Q17
R17
Q14
12 kΩ
R18
20kΩ
Q26
Q25
Q24
OUT
SENSE
R27
V TAP
R28
R13
100
kΩ
Q18
Q21
C2
40 pF
R14
350
kΩ
Q29
Q19
Q22
Q23
R15
100 kΩ
R16
30 kΩ
R17
10 Ω
Q28
R22
150 kΩ
Q30 Q31
R21 8 Ω
R24
R23 60 kΩ
50 kΩ
SHDN
GND
DENOTES CONNECTION ON FIXED
VOLTAGE VERSIONS ONLY
MIC2940A/2941A
2
June 1999