FSF-5050 Series · SAW Bandpass Filter
470 & 475 MHz SAW Bandpass Filters
FSF-5050-470M · FSF-5050-475M
Two frequency options for UHF signal selection and receiver front-end filtering in a 5.0 × 5.0 mm SMD package.
Left: marked top surface. Right: pad side. Photos do not define pin orientation.
Model Selection
Choose the Passband for Your Design
The two models share a package but use different passbands, operating ranges and test arrangements. Their insertion-loss values apply over different frequency intervals and do not establish interchangeability.
Matching network requires confirmation; L and C values not supplied
FSF-5050-470M
470 MHz
Center frequency (Typ.)
- Specified passband
- 468–472 MHz
- Insertion loss over that passband
- 4.0 dB max.
- Passband ripple
- 2.0 dB max.
- Operating temperature
- −10 to +50 °C
Ripple unit pending confirmation
FSF-5050-475M
475 MHz
Center frequency (Typ.)
- Specified passband
- 469–481 MHz
- Insertion loss over that passband
- 2.1 dB typ. / 3.3 dB max.
- Passband ripple
- 0.7 dB typ. / 1.7 dB max.*
- Operating temperature
- 0 to +50 °C
These models use different passbands, operating ranges and test arrangements. Their insertion-loss values apply over different frequency intervals and do not establish interchangeability.
Electrical Specifications
Model-Specific Limits and Conditions
The spans below are specified passbands, not 3 dB bandwidths. “—” means a value is not supplied; it does not mean zero. Typical values are for design guidance.
FSF-5050-470M
Scroll horizontally to view all columns.
| Parameter | Min. | Typ. | Max. | Unit | Definition / condition |
|---|---|---|---|---|---|
| Center frequency | — | 470.0 | — | MHz | As listed in the FCom Typ. column |
| Specified passband | — | — | — | MHz | 468–472; insertion-loss and ripple interval |
| Insertion loss | — | — | 4.0 | dB | 468–472 MHz |
| Passband ripple | — | — | 2.0 | dB | 468–472 MHz |
| 3 dB bandwidth | — | — | — | MHz | Not provided |
| Operating temperature | −10 | — | +50 | °C | Operating range; not storage temperature |
Matching-network element values (L and C) are not supplied for this model. Confirm the applicable network and test conditions with FCom before design-in.
FSF-5050-475M
Scroll horizontally to view all columns.
| Parameter | Min. | Typ. | Max. | Unit | Definition / condition |
|---|---|---|---|---|---|
| Center frequency | — | 475.0 | — | MHz | As listed in the FCom Typ. column |
| Specified passband | — | — | — | MHz | 469–481; insertion-loss and ripple interval |
| Insertion loss | — | 2.1 | 3.3 | dB | 469–481 MHz |
| Passband ripple | — | 0.7 | 1.7 | dB* | 469–481 MHz; unit pending confirmation |
| 3 dB bandwidth | — | — | — | MHz | Not provided |
| Operating temperature | 0 | — | +50 | °C | Operating range; not storage temperature |
* The FCom sheet retains dB for ripple, with confirmation pending. Confirm the ripple unit with FCom before using these values as a design requirement.
Both models list −40 to +85 °C storage temperature. This is separate from each model’s operating range. The supplied sheets do not state a common measurement temperature for the electrical tables. Consult the FCom combined datasheet for the complete supplied information and confirm applicable production limits with FCom.
Typical Applications
UHF Signal Selection
Receiver front-end filtering
Use a bandpass stage to select the required RF band around 470 or 475 MHz ahead of subsequent receiver processing. Check the wanted-signal spectrum against the model’s specified passband.
Custom RF band selection
Evaluate the appropriate model in a custom UHF signal path where passband loss, temperature and interface requirements match the application. Confirm rejection requirements and the response before committing the design.
Integration Notes
Confirm the Interface Before PCB Release
470 MHz: matching conditions
At the center frequency, the FCom sheet lists both device impedances as 50 Ω ∥ 0 pF. Test ports are 50 Ω.
The described circuit includes 50 Ω series resistors and shunt L / adjustable C at each port. L and C values are not provided. Confirm the network and its applicable test conditions with FCom; do not infer a component-free connection.
475 MHz: test terminations
The FCom sheet specifies 50 Ω source and load, with no matching components shown. Input and output device impedances are not specified.
Confirm compatibility with the intended source and load, along with the ripple unit, before using the tabulated performance in the design.
Package & Pin Assignment
Shared 5.0 × 5.0 mm, Eight-Pad Package
Both FCom models use a leadless SMD package with a maximum height of 1.5 mm. The following functions are reproduced from the applicable FCom sheets.
Mechanical information is included on each model’s page in the combined FCom datasheet. Confirm the pad orientation and applicable footprint from the FCom drawing before layout release. Contact FCom for other pin configurations.
| Pin number | FCom description |
|---|---|
| 2 | Input / Output |
| 6 | Input / Output |
| 1, 3, 5, 7 | To be grounded |
| 4, 8 | Case ground |
Selection and Design-In Support
Discuss Your Signal Path with FCom
Provide the selected model or center frequency, required passband and bandwidth definition, source/load requirements, operating temperature, sample quantity and estimated usage. Include matching-network questions for 470 MHz or ripple-unit and impedance questions for 475 MHz. Confirm the complete ordering code before placing an order.
Engineering Questions
Frequently Asked Questions
How do I choose between the 470 MHz and 475 MHz models?
Choose by the required signal band and operating conditions. FSF-5050-470M specifies insertion loss and ripple over 468–472 MHz and operates from −10 to +50 °C. FSF-5050-475M specifies these characteristics over 469–481 MHz and operates from 0 to +50 °C. Their matching conditions differ, so the models should not be treated as direct substitutes.
Are the 4 MHz and 12 MHz spans the 3 dB bandwidths?
No. They are the spans of the specified passbands, 468–472 MHz and 469–481 MHz, over which insertion loss and ripple are stated. Neither FCom datasheet provides a 3 dB bandwidth value.
Does the 470 MHz model need a matching network?
The 470 MHz datasheet lists input and output device impedances of 50 Ω in parallel with 0 pF at the center frequency. It also describes a test circuit with 50 Ω series resistors and shunt inductor / adjustable-capacitor elements at each port. Inductor and capacitor values are not supplied. Confirm the applicable matching network with FCom before design-in.
Is the 475 MHz model a confirmed 50 Ω device?
The 475 MHz data uses 50 Ω source and load test terminations, with no matching components shown. Device input and output impedances are not specified. The FCom datasheet lists ripple as 0.7 dB typical and 1.7 dB maximum over 469–481 MHz, but explicitly marks the unit as pending confirmation. Confirm the interface and ripple unit before use.
Do the two models use the same package and pins?
Both FCom pages specify an eight-pad, leadless 5.0 × 5.0 mm SMD package with a maximum height of 1.5 mm. Pins 2 and 6 are signal input/output, pins 1, 3, 5 and 7 are to be grounded, and pins 4 and 8 are case ground. Confirm pad orientation and the applicable footprint from the FCom drawing before PCB release.
What information should I include in an inquiry?
Include the selected model or center frequency, required passband and bandwidth definition, source and load requirements, operating temperature, sample quantity and estimated usage. For FSF-5050-470M, request matching-network confirmation; for FSF-5050-475M, request ripple-unit and device-impedance confirmation. Ask FCom to confirm the complete ordering code.