LD1117S STMicroelectronics, LD1117S Datasheet - Page 17
![IC, V REG ADJ +1.25/15V, SMD, 1117](/photos/19/8/190894/42334025_sml.jpg)
LD1117S
Manufacturer Part Number
LD1117S
Description
IC, V REG ADJ +1.25/15V, SMD, 1117
Manufacturer
STMicroelectronics
Datasheet
1.LD1117S.pdf
(27 pages)
Specifications of LD1117S
Primary Input Voltage
13.75V
Output Voltage Adjustable Range
1.2V To 5V
Dropout Voltage Vdo
1.1V
No. Of Outputs
1
No. Of Pins
3
Output Current
800mA
Voltage Regulator Case Style
SOT-223
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
LD1117S
Manufacturer:
FSC
Quantity:
6 000
Part Number:
LD1117S-2.5TR
Manufacturer:
ST
Quantity:
20 000
Part Number:
LD1117S-3.3TR
Manufacturer:
ST
Quantity:
20 000
Company:
Part Number:
LD1117S-3.3V
Manufacturer:
NSC
Quantity:
1 716
Figure 10: Post-Regulated Dual Supply
LD1117 ADJUSTABLE: APPLICATION NOTE
The LD1117 ADJUSTABLE has a thermal
stabilized 1.25±0.012V reference voltage between
the OUT and ADJ pins. I
max.) and ∆I
R1 is normally fixed to 120Ω. From figure 11 we
obtain:
V
+V
In normal application R2 value is in the range of
few kohm, so the R2 x I
considered in the V
above expression becomes:
OUT
REF
= V
/R1) = V
REF
ADJ
+ R2 (I
REF
is 1µA typ. (5µA max.).
(1 + R2 / R1) + R2 x I
ADJ
OUT
ADJ
DJ
+I
R1
calculation; then the
product could not be
is 60µA typ. (120µA
) = V
REF
+ R2 (I
ADJ
.
ADJ
V
In order to have the better load regulation it is
important to realize a good Kelvin connection of
R1 and R2 resistors. In particular R1 connection
must be realized very close to OUT and ADJ pin,
while R2 ground connection must be placed as
near as possible to the negative Load pin. Ripple
rejection can be improved by introducing a 10µF
electrolytic capacitor placed in parallel to the R2
resistor (see Fig. 12).
OUT
= V
REF
(1 + R2 / R1).
LD1117 SERIES
17/27