LD1117xx
Low drop fixed and adjustable positive voltage regulators
Features
■
Low dropout voltage (1 V typ.)
■
2.85 V device performances are suitable for
SCSI-2 active termination
■
Output current up to 800 mA
■
Fixed output voltage of: 1.2 V, 1.8 V, 2.5 V,
2.85 V, 3.0 V, 3.3 V, 5.0 V
■
Adjustable version availability (Vref = 1.25 V)
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Internal current and thermal limit
■
Available in ± 1% (at 25 °C) and 2% in full
temperature range
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Supply voltage rejection: 75 dB (typ.)
DPAK
TO-220
SOT-223
Description
The LD1117 is a low drop voltage regulator able
to provide up to 800 mA of output current,
available even in adjustable version (VREF = 1.25
V). Concerning fixed versions, are offered the
following output voltages: 1.2 V, 1.8 V, 2.5 V, 2.85
V, 3.0 V, 3.3 V and 5.0 V. The 2.85 V type is ideal
for SCSI-2 lines active termination. The device is
supplied in: SOT-223, DPAK, SO-8 and TO-220.
SO-8
High efficiency is assured by NPN pass transistor.
In fact in this case, unlike than PNP one, the
quiescent current flows mostly into the load. Only
a very common 10 µF minimum capacitor is
needed for stability. On chip trimming allows the
regulator to reach a very tight output voltage
tolerance, within ± 1% at 25°C. The adjustable
LD1117 is pin to pin compatible with the other
standard. Adjustable voltage regulators
maintaining the better performances in terms of
drop and tolerance.
The SOT-223 and DPAK surface mount packages
optimize the thermal characteristics even offering
a relevant space saving effect.
Table 1.
Device summary
Part numbers
LD1117XX12
LD1117XX50
LD1117XX12C
LD1117XX28
LD1117XX50C
LD1117XX18
LD1117XX30
LD1117XX
LD1117XX18C
LD1117XX33
LD1117XXC
LD1117XX25
March 2009
LD1117XX25C
LD1117XX33C
Rev 25
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