LExxAB
LExxC
Very low drop voltage regulators with inhibit
Features
■
■
■
■
■
■
■
■
■
Very low dropout voltage (0.2 V typ)
Very low quiescent current (typ. 50 µA in OFF
MODE, 0.5 mA in ON MODE, no load)
Output current up to 100 mA
Output voltages of 2.5; 2.7; 3; 3.3; 3.5; 4; 4.5;
4.7; 5; 8 V
Internal current and thermal limit
Only 2.2 µF for stability
Available in ± 1 % (A) or ± 2 % (C) selection at
25 °C
Supply voltage rejection: 80 dB (typ.)
Temperature range: -40 to 125 °C
TO-92
SO-8
Description
The LExxAB and LExxC are very low drop voltage
regulators available in SO-8 and TO-92 packages
and in a wide range of output voltages.
The very low drop voltage (0.2 V) and the very low
quiescent current make them particularly suitable
for low noise low power applications and specially
in battery powered systems.
They are pin to pin compatible with the older
L78Lxx series. Furthermore in the 8 pin
configuration (SO-8) they employ a shutdown
logic control (pin 5, TTL compatible). This means
that when the device is used as a local regulator,
it’s possible to put in stand by a part of the board
even more decreasing the total power
consumption. In the three terminal configuration
(TO-92) the device is even in ON STATE,
maintaining the same electrical performances. It
needs only 2.2 µF capacitor for stability allowing
room and cost saving effect.
Table 1.
Device summary
Part numbers
LE25AB
LE27AB
LE30C
LE33C
LE33AB
LE35C
LE35AB
LE40C
LE45C
LE45AB
Rev 12
LE47AB
LE50C
LE50AB
LE80C
LE80AB
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July 2008
Contents
LExxAB LExxC
Contents
1
2
3
4
5
6
7
8
Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Typical performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Order codes
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
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LExxAB LExxC
List of figures
List of figures
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Pin connections (top view for SO-8, bottom view for TO-92) . . . . . . . . . . . . . . . . . . . . . . . . 6
Test circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Dropout voltage vs output current. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Dropout voltage vs temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Supply current vs temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Supply current vs input voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Short circuit current vs dropout voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
SVR vs frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Logic controlled precision 3.3/5.0 V selectable output . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Sequential multi-output supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Multiple supply with ON/OFF toggle switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Basic inhibit functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
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List of tables
LExxAB LExxC
List of tables
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Table 7.
Table 8.
Table 9.
Table 10.
Table 11.
Table 12.
Table 13.
Table 14.
Table 15.
Table 16.
Table 17.
Table 18.
Table 19.
Table 20.
Table 21.
Table 22.
Table 23.
Table 24.
Table 25.
Table 26.
Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical characteristics for LE12AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Electrical characteristics for LE25AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Electrical characteristics for LE25C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Electrical characteristics for LE27AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Electrical characteristics for LE27C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Electrical characteristics for LE30AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Electrical characteristics for LE30C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Electrical characteristics for LE33AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Electrical characteristics for LE33C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Electrical characteristics for LE35AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Electrical characteristics for LE35C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Electrical characteristics for LE40AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Electrical characteristics for LE40C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Electrical characteristics for LE45AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Electrical characteristics for LE45C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Electrical characteristics for LE47AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Electrical characteristics for LE47C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Electrical characteristics for LE50AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Electrical characteristics for LE50C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Electrical characteristics for LE80AB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Electrical characteristics for LE80C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Order codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
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LExxAB LExxC
Diagram
1
Figure 1.
Diagram
Block diagram
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