D1787-AL

Document 484-1
Shielded Power Inductor
For National Semiconductor
LM5115 DC Controller IC
The D1787-AL was developed for use with the National
Semiconductor LM5115 Secondary Side Post Regulator
Controller and LM5025 Primary Side Controller. This flat
wire power inductor offers extremely low dc resistance
and very high current ratings (up to 23 Arms). The flat
core allows for exceptional heat dissipation and provides
an excellent surface for pick and place operation.
This inductor is ideal for power supply applications where
high current handling is essential and is perfect for lowvoltage dc-dc converters. Custom inductance values are
also possible.
Request free evaluation samples by contacting Coilcraft
or visiting www.coilcraft.com.
D1787-AL
33.0
2.8
9.0
Isat3 Irms4
(A)
(A)
8.0
23.0
1. Inductance measured at 100 kHz, 0.1 Vrms, 0 Adc using Coilcraft
SMD‑D fixture in Agilent/HP 4284A impedance analyzer.
2. SRF measured using Agilent/HP 8753D network analyzer and Coilcraft
SMD­‑D test fixture.
3. DC current at which the inductance drops 20% (typ) from its value without current. Click for temperature derating information.
4. Current that causes a 40°C rise from 25°C ambient. This information is
for reference only and does not represent absolute maximum ratings.
Click for temperature derating information.
5. Electrical specifications at 25°C.
Refer to Doc 362 “Soldering Surface Mount Components” before soldering.
Temperature Rise vs Current
Temperature rise (from 25°C)
DCR SRF
Part Inductance1max typ2
number ±10% (µH) (mOhms) (MHz)
Core material Ferrite
Core and winding loss See www.coilcraft.com/coreloss
Terminations RoHS tin-silver (96.5/3.5) over copper
Weight 34.9 g
Ambient temperature –40°C to +85°C with (40°C rise) Irms current.
Maximum part temperature +125°C (ambient + temp rise). Derating.
Storage temperature Component: –40°C to +125°C.
Tape and reel packaging: –40°C to +80°C
Resistance to soldering heat Max three 40 second reflows at
+260°C, parts cooled to room temperature between cycles
Moisture Sensitivity Level (MSL) 1 (unlimited floor life at <30°C /
85% relative humidity)
Failures in Time (FIT) / Mean Time Between Failures (MTBF)
38 per billion hours / 26,315,789 hours, calculated per Telcordia SR-332
Packaging 25 pieces per tray
PCB washing Tested to MIL-STD-202 Method 215 plus an additional
aqueous wash. See Doc787_PCB_Washing.pdf.
50
45
40
35
30
25
20
15
10
5
0
0
5
10
15
20
25
30
35
Current (A rms)
Document 484-1 Revised 09/10/15
Document 484-2
SMT Power Inductor - D1787-AL
Typical L vs Frequency
Typical L vs Current
1000
Inductance (µH)
Inductance (µH)
1000
100
10
100
10
0.1
10
1
100
0.1
D1787-AL
XXXXY
100
Current (A)
1.10
max
27,9
1.100
max
27,94
10
1
Frequency (MHz)
Recommended
Land Pattern
0.77
max
19,6
Parts manufactured prior
to December 2011 may
be marked differently.
CL
0.455
11,56
0.220
5,59
0.160
4,06
0.240
6,10
0.210
5,33
0.190
4,83
0.655
max
16,6
0.004/0,102
Dimensions are in
inches
mm
0.150
3,8
0.270
6,9
Document 484-2 Revised 09/10/15