ISO 9001 Registered
IMP1117
1A Adjustable/Fixed Low Dropout Linear Regulator
Daily Silver IMP www.ds-imp.com.cn 1
- Low dropout voltage
- Load regulation: 0.2% typical
- Optimized for Low Voltage
- On-chip thermal limiting
- Standard SOT-223 and TO-252 packages
- Three-terminal adjustable or fixed low dropout
1.2V,1.5V,1.8V, 2.5V, 2.85V, 3.3V, 5V. Regulators
- Active SCSI terminators
- High efficiency linear regulators
- Post regulators for switching supplies
- Battery chargers
- 12V to 5V linear regulators
- Motherboard clock supplies
The IMP1117-ADJ and IMP1117-1.2,-1.5,-1.8,-2.5,-2.85,
-3.3 and-5 are low dropout three-terminal regulators with
1A output current capability. These devices have been
optimized for low voltage where transient response and
minimum input voltage are critical. The 2.85V version is
designed specifically to be used in Active Terminators for
SCSI bus.
On-chip thermal limiting provides protection against any
combination of overload and ambient temperatures that
would create excessive junction temperatures.
Unlike PNP type regulators where up to 10% of the output
current is wasted as quiescent current, the quiescent cur-
rent of the IMP1117 flows into the load, increasing effi-
ciency.
The IMP1117 series regulators are available in the indus-
try-standard SOT-223 and TO-252 power packages.
Key Features
Applications
General Description
T ypical Application
Notice: The distance between Vout pin and Capacitor should not exceed 4cm for excellent performance
Figure 1. Typical Applications of IMP1117
V
OUT
=V
REF
(1+R2/R1)+I
ADJ
*R2
IMP1117-ADJ
ADJ
V
IN
V
OUT
V
IN
=5V
10uF
+
R1
124
R2
175
22uF
+
3V
IMP1117-1.8
GND
V
IN
V
OUT
V
IN
=4.75V
10uF
+
22uF
+
1.8V
ISO 9001 Registered
IMP1117
1A Adjustable/Fixed Low Dropout Linear Regulator
Daily Silver IMP www.ds-imp.com.cn 2
Pin Assignments
*With package soldered to 0.5 square inch copper area over backside ground plane or internal power plane, Θ
JA
can vary from 30°C/W to
more than 50°C/W. Other mounting techniques may provide better thermal resistance than 30°C/W.
Absolute Maximum Ratings
Figure 3. Absolute Maximum Safe Operating Area
I
OUT
(A)
V
IN
-V
IN
(V)
Figure 2. Pin Assignments of IMP1117
Parameter Min. Max. Unit
V
IN
18 V
(V
IN
– V
OUT
) * I
OUT
See Figure 3
Operating Junction Temperature Range
0 125
°C
Storage Temperature Range
-65 150
°C
Lead Temperature (Soldering, 10 sec.)
300
°C
Front View
Tab is
V
OUT
3
2
1
IN
OUT
ADJ/GND
4-Lead Plastic SOT-223
Θ
JC
=15°C/W*
3-Lead Plastic TO-252
Θ
JC
=3°C/W*
Front View
Tab is V
OUT
321
IN
OUT
ADJ/
GND