Datasheet
3D Model
ST312RAJ Series
Chip Inductors for Critical Applications
ST312RAJ Series inductors feature high current ratings and a small size, making them ideal for high frequency and low voltage applications.
- Continuous current ratings up to 2.4 Amps DC and handles transient currents up to 50% higher.
- Higher Q factor than the 0603CS at lower inductance values.
- Matte tin over nickel over silver-platinum glass frit terminations.
Specifications
Electrical specifications at 25°C.
| Part number 1 | Inductance (nH) 2 | Tolerance (%) 3 | 900 MHz | 1.7 GHz |
Q min
@ 250 MHz 4 |
SRF min (GHz) 5 | DCR max (Ω) 6 | Imax (A) | ||
|---|---|---|---|---|---|---|---|---|---|---|
| L typ | Q typ 4 | L typ | Q typ 4 | |||||||
| ST312RAJ1N6JRZ | 1.6 | 5 | 1.67 | 49 | 1.65 | 63 | 24 | > 5.0 | 0.030 | 2.4 |
| ST312RAJ3N6JRZ | 3.6 | 5 | 3.65 | 70 | 3.75 | 90 | 24 | > 5.0 | 0.048 | 1.8 |
| ST312RAJ3N9JRZ | 3.9 | 5 | 3.74 | 70 | 3.9 | 90 | 25 | > 5.0 | 0.054 | 1.8 |
| ST312RAJ6N8JRZ | 6.8 | 5 | 6.72 | 70 | 7.1 | 75 | 35 | > 5.0 | 0.054 | 1.5 |
| ST312RAJ7N5JRZ | 7.5 | 5 | 7.33 | 70 | 7.9 | 68 | 38 | 3.7 | 0.059 | 1.5 |
| ST312RAJ10N_RZ | 10 | 5,2 | 9.7 | 73 | 10.5 | 57 | 38 | 3.7 | 0.071 | 1.3 |
| ST312RAJ12N_RZ | 12 | 5,2 | 12.3 | 68 | 14.5 | 41 | 38 | 3.0 | 0.075 | 1.3 |
| ST312RAJ15N_RZ | 15 | 5,2 | 15.5 | 65 | 17.6 | 40 | 38 | 2.8 | 0.080 | 1.2 |
| ST312RAJ18N_RZ | 18 | 5,2 | 19.5 | 62 | 25 | 40 | 40 | 2.8 | 0.099 | 1.1 |
| ST312RAJ22N_RZ | 22 | 5,2 | 24 | 61 | 31.5 | 26 | 42 | 2.4 | 0.099 | 1.1 |
| ST312RAJ24N_RZ | 24 | 5,2 | 25.8 | 55 | 35 | 21 | 42 | 2.4 | 0.105 | 1.1 |
| ST312RAJ33NJRZ | 33 | 5 | 34.3 | 50 | - | - | 47 | 1.9 | 0.175 | 0.85 |
| ST312RAJ47NJRZ | 47 | 5 | 49.5 | 45 | - | - | 40 | 1.5 | 0.195 | 0.75 |
Notes
- When ordering, specify tolerance, termination and screening codes: e.g. ST312RAJ47NJRZ.
- Inductance measured at 250 MHz using Coilcraft SMD-A fixture in Agilent/HP 4286 impedance analyzer with Coilcraft-provided correlation pieces.
- Tolerances in bold are stocked for immediate shipment.
- Q measured at 250 MHz using Agilent/HP 4291A with Agilent/HP 16193 test fixture.
- SRF measured using Agilent/HP 8720D network analyzer and Coilcraft SMD-D test fixture.
- DCR measured on micro-ohmmeter and Coilcraft CCF858 test fixture.
Tolerance:
- G = 2%
- J = 5% (Table shows stock tolerances in bold.)
Termination:
- R = Matte tin over nickel over silver-platinum glass frit
- L = Silver-palladium-platinum glass frit.
- P = Tin-lead (63/37) over tin over nickel over silver-platinum-glass frit.
- Q = Tin-silver-copper (95.5/4/0.5) over tin over nickel over silver-platinum-glass frit.
- S = Tin-lead (63/37) over silver-platinum-glass frit.
- T = Tin-silver-copper (95.5/4/0.5) over silver-platinum glass frit.
Screening:
- Z = Unscreened
- H = Coilcraft CP-SA-10001 Group A
- Screening performed to the document’s latest revision.
- Lot qualification (Group B) available.
- Custom testing also available.
- Country of origin restrictions available; prefix options G or F.
Environmental
Ambient temperature range:
–40°C to +125°C with Irms current.
Storage temperature range:
Component: –55°C to +145°C.
Tape and reel packaging: –55°C to +80°C.
Tape and reel packaging: –55°C to +80°C.
Maximum part temperature:
+145°C (ambient + temp rise).
Failures in Time (FIT) / Mean Time Between Failures (MTBF):
Performance curves
Typical Q vs Frequency
Typical L vs Frequency
Physical characteristics
| A max | B max | C max | D ref | E | F | G | H | I | J | |
|---|---|---|---|---|---|---|---|---|---|---|
| 0.071 | 0.044 | 0.040 | 0.015 | 0.030 | 0.013 | 0.034 | 0.040 | 0.025 | 0.025 | inches |
| 1,80 | 1,12 | 1,02 | 0,38 | 0,76 | 0,33 | 0,86 | 1,02 | 0,64 | 0,64 | mm |
Dimensions are for solder application. For maximum overall dimensions including solder,
add 0.0025 in / 0.064 mm to B and 0.006 in / 0,15 mm to A and C.
General specification
Core Material:
Ceramic
Weight:
3.3 – 5.7 mg
Packaging:
2000 per 7′′ reel. Paper tape: 8 mm wide, 1.0 mm thick, 4 mm pocket spacing
Temperature coefficient of inductance:
+25 to +125 ppm/°C.
Soldering/Washing
Moisture Sensitivity Level (MSL):
1 (unlimited floor life at <30°C / 85% relative humidity).
Resistance to soldering heat:
Max three 40 second reflows at +260°C, parts cooled to room temperature between cycles.
Refer to Soldering Coilcraft Components before soldering.
PCB Washing:
Tested to MIL-STD-202 Method 215 plus an additional aqueous wash. See Doc787_PCB_Washing.pdf.