LD2979xx
Very low drop voltage regulators with inhibit
Features
■Very low dropout voltage (0.2 V typ. at 50 mA load)
■ Very low quiescent current (typ. 500 µA at 50 mA load)
■Output current up to 50 mA
■Logic-controlled electronic shutdown
SOT23-5L
■Output voltages of 3.0; 3.3; 3.8; 5.0 V
■Internal current and thermal limit
■Supply voltage rejection: 63 dB (typ)
■Only 1 µF for stability
■Selection at 25 °C
■Temperature range: -25 °C to 125 °C
■Package available: SOT23-5L
Description
The LD2979 series are very low drop regulators available in SOT23-5L.
The very low drop-voltage and the very low quiescent current make them particularly suitable for low noise, low power applications and in battery powered systems.
Shutdown logic control function is available on five pin version (TTL compatible). This means that
when the device is used as local regulator, it is possible to put a part of the board in standby, decreasing the total power consumption.
Table 1. |
Device summary |
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Part numbers |
Order codes |
Output voltages |
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LD2979XX30 |
LD2979M30TR |
3.0 V |
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LD2979XX33 |
LD2979M33TR |
3.3 V |
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LD2979XX38 |
LD2979M38TR |
3.8 V |
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LD2979XX50 |
LD2979M50TR |
5.0 V |
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April 2008 |
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Rev 14 |
1/15 |
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www.st.com |
Contents |
LD2979xx |
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Contents
1 |
Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
. 3 |
2 |
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
. 4 |
3 |
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
5 |
4 |
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
6 |
5 |
Typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
8 |
6 |
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
11 |
7 |
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
14 |
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LD2979xx |
Diagram |
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3/15
Pin configuration |
LD2979xx |
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SOT23-5L
Table 2. |
Pin description |
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Symbol |
Name and function |
Pin number |
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VI |
Input voltage |
1 |
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GND |
Ground |
2 |
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INHIBIT |
Control switch ON/OFF (1) |
3 |
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NC |
Not to be connected |
4 |
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VO |
Output voltage |
5 |
1.Inhibit pin is not internally pulled-up then it must not be left floating. Connect to a positive voltage higher than 2 V to able the device.
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LD2979xx |
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Maximum ratings |
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3 |
Maximum ratings |
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Table 3. |
Absolute maximum ratings |
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Symbol |
Parameter |
Value |
Unit |
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VI |
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DC input voltage |
16 |
V |
VINH |
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DC inhibit input voltage |
VIN |
V |
IO |
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Output current |
Internally limited |
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PD |
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Power dissipation |
Internally limited |
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TSTG |
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Storage temperature range |
-40 to 150 |
°C |
TOP |
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Operating junction temperature range |
-25 to 125 |
°C |
Note: |
Absolute maximum ratings are those values beyond which damage to the device may occur. |
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Functional operation under these condition is not implied. |
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