Cross-Reference Analysis of RTV-104AF328Y-S-19.200-TR VCTCXO
RTV-104AF328Y-S-19.200-TRThe RTV-104AF328Y-S-19.200-TR is a voltage-controlled temperature-compensated crystal oscillator (VCTCXO) from Raltron delivering a 19.2 MHz clipped sine wave output at 2.8V supply. This component belongs to the Oscillators category and serves as a precision frequency reference for applications where frequency stability over temperature and voltage tuning capability are mandatory, such as 5G base station phase-locked loops, GPS receivers, and small-cell backhaul modules. The RTV-104AF328Y-S-19.200-TR datasheet specifies a 3.2mm x 2.5mm ceramic SMD package with no leads, enabling direct reflow assembly into tight timing chains.
Core Specifications of RTV-104AF328Y-S-19.200-TR
The following table consolidates the key electrical and mechanical parameters for this part. For missing data, consult the latest RTV-104AF328Y-S-19.200-TR datasheet.
| Parameter | Value | Engineering Meaning |
|---|---|---|
| Base Resonator | Crystal | Quartz-based AT-cut or similar fundamental mode crystal used as the resonator element. |
| Type | VCTCXO | Temperature-compensated oscillator with voltage control input. This indicates both automatic stabilization against thermal drift plus manual frequency trim capability. |
| Frequency | 19.2 MHz | Common reference for cellular baseband, Wi-Fi, and Ethernet clock multipliers. Many PLLs use 19.2 MHz as a base integer times 26, 52 or 104 MHz. |
| Output | Clipped Sine Wave | Typically 0.8V p-p swing centered around 0.5V supply rail. Lower harmonic content than square-wave oscillators, reducing EMI radiated from output traces. |
| Voltage - Supply | 2.8V | Single rail supply. A non-standard voltage — most logic uses 1.8V, 2.5V, or 3.3V. This 2.8V indicates a specific module or chipset requiring this level. |
| Mounting Type | Surface Mount | Reflow-solderable, no through-hole leads. Compatible with automated pick-and-place lines. |
| Package / Case | 4-SMD, No Lead | Four-pad ceramic LCC package. Pad layout typically 1.0mm pitch. Requires footprint with matched ground plane cutouts. |
| Size / Dimension | 3.20mm x 2.50mm | Compact form factor (0.126"x0.098") for space-constrained RF modules and handheld test equipment. |
| Height - Seated (Max) | 0.90mm | Low-profile design for stacking under shields or between PCB layers. |
| RoHS | Compliant | — |
| Frequency Stability vs Temp | Specialty parameter — see datasheet | Expected range for TCXO: ±0.5 to ±2.5 ppm over -40°C to +85°C. Confirm the actual grade from Raltron's documentation. |
| Aging | Specialty parameter — see datasheet | Typical VCTCXO aging: ±1 ppm/year at 25°C. First-year aging may be slightly higher due to crystal lattice settling. |
Critical Design Implications of 2.8V Supply and Clipped Sine Output
The 2.8V supply rail is the most distinctive specification of the RTV-104AF328Y-S-19.200-TR. Standard logic supply families are 1.8V, 2.5V, or 3.3V. A 2.8V VCTCXO typically interfaces with a chipset that includes an internal LDO regulated at 2.8V, common in Qualcomm and MediaTek baseband processors for 4G/5G. Engineers substituting this oscillator must verify that the system's power domain matches exactly — feeding 3.3V into a 2.8V rated oscillator will exceed the absolute maximum ratings, while 2.5V under-supply may degrade startup margin and push output voltage swing below the receiver's minimum logic-high threshold.
Clipped sine wave output requires careful termination. Unlike CMOS oscillators that can drive multiple gates directly, clipped sine wave signals expect a DC bias at around 0.5VDD and typically need an AC-coupling capacitor (0.01 μF to 0.1 μF) before feeding into a PLL's reference input. Many engineers have reported frequency pulling when the load capacitance at the output deviates from the 10pF to 15pF typical load. Use the oscillator's internal pull-up circuit — do not add an external pull-up resistor unless the datasheet explicitly calls for it.
Parameters That Must Match vs. Those That Can Be Relaxed for Substitution
When cross-referencing the RTV-104AF328Y-S-19.200-TR equivalent, the following parameters are non-negotiable:
- Supply voltage (2.8V): A 2.5V or 3.3V oscillator cannot drop into the same socket without changing the power rail or risking damage.
- Frequency (19.2 MHz): PLL feedback dividers are integer-based — a 19.2 MHz crystal generates 61.44 MHz, 122.88 MHz, etc. Substituting with 20 MHz or 19.44 MHz will break system synchronization.
- Package footprint (3.2 x 2.5 mm, 4-pad): Mechanical pinout must be identical. Even a 2.0 x 1.6 mm version of the same part will require PCB respin.
- Output waveform (clipped sine): Cannot substitute with full-swing CMOS — the DC level mismatch will saturate the receiver's input stage.
Parameters with some relaxation allowance:
- Frequency stability over temperature: A ±2.0 ppm VCTCXO can replace a ±0.5 ppm unit only if the system has sufficient PLL bandwidth to track slower thermal drift. For GPS holdover applications, replace only with same or better stability.
- Aging spec: ±1.0 ppm/year versus ±0.5 ppm/year — in short-life consumer products the difference is negligible; in 10-year industrial designs, it matters.
- Phase noise: Not all datasheets publish phase noise at the same offset. A substitution candidate with -142 dBc/Hz at 1 kHz offset is acceptable if the original spec is -140 dBc/Hz. Confirm floor noise requirements via system jitter budget.
Cross-Reference Brands and Substitution Methodology
RTV-104AF328Y-S-19.200-TR cross reference searches typically return candidates from Epson, NDK, Kyocera, and TXC. The substitution methodology should follow a four-step validation sequence:
- Pin-to-pin compatibility: Compare pad assignments (pin 1 = VC control, pin 2 = GND, pin 3 = output, pin 4 = VDD). Some manufacturers swap VC and OE functions. Always order a sample sheet or download the candidate's mechanical drawing.
- Electrical consistency check at 25°C: Apply 2.8V ±5%, measure frequency deviation, output amplitude (Vp-p into 10kΩ//10pF), and startup time. The candidate must start within 2 ms and settle to within ±1 ppm of nominal frequency at 25°C.
- Temperature cycling: Run -40°C to +85°C at 5°C/min ramp, measuring frequency drift every 10°C. Plot against RTV-104AF328Y-S-19.200-TR datasheet stability curves. Any deviation exceeding 20% of the datasheet's guaranteed stability window indicates a mismatch in resonator aging rate or compensation algorithm.
- Long-term aging (burn-in): 168 hours at 85°C with constant 2.8V supply. Measure frequency at 0, 24, 48, 168 hours. Drift should not exceed the datasheet's first-year aging spec. Higher drift suggests different crystal blank quality or contamination in the hermetic seal.
Supply-Chain Risk and Toolchain Compatibility
The RTV-104AF328Y-S-19.200-TR distributor stock profile shows this part belongs to a high-reliability product line used in telecom infrastructure with typical lead times of 12 to 16 weeks during peak demand cycles. When evaluating alternative parts for second-source qualification, consider that non-Raltron substitutes may require updated emulator configurations in your ATE test fixtures — particularly if the substitute measures output frequency under different load capacitance. Design tools such as phase noise simulation (Keysight ADS, NI AWR) may need oscillator Spice models or .s2p files. Most manufacturers provide S-parameter files for their oscillators; confirm the candidate model's S-parameter frequency range extends to at least the third harmonic (57.6 MHz) to capture spurious modes.
When NOT to Substitute: Honest Engineering Boundaries
Substitution is inadvisable in the following scenarios:
- OCXO-grade holdover circuits: A VCTCXO (even with voltage control) does not have the thermal mass or double-oven construction of an OCXO. If the system requires <±0.01 ppm accuracy for 24 hours of holdover, a standard VCTCXO will not suffice.
- Radiation-hardened or space-grade designs: The RTV-104AF328Y-S-19.200-TR is not screened for total ionizing dose effects. Industrial substitutes from Abracon or SiTime may use plastic packages unsuitable for space environments.
- Designs with strict voltage-control linearity (5G CPRI): If the application uses the VC pin to perform real-time PLL phase correction, linearity tolerance (typically ±5% to ±10%) must match exactly. Some substitutes have different tuning curves (negative-slope vs positive-slope control).
Substitution Decision Matrix for RTV-104AF328Y-S-19.200-TR
| Decision Criteria | Must Match (Critical) | Can Relax (Depends on Application) |
|---|---|---|
| Supply voltage | 2.8V ±5% | — |
| Frequency | 19.200 MHz ±0 ppm at 25°C | — |
| Output waveform | Clipped sine | If downstream uses AC-coupled comparator, CMOS may work with level-shifter resistor network (extra BOM cost) |
| Package / footprint | 3.2mm x 2.5mm x 0.9mm, 4-pad no lead | Larger or smaller package requires new PCB layout |
| Frequency stability | Application-dependent (e.g., GPS ±0.5 ppm) | Yes — 0.5 ppm can replace 2.0 ppm, but not vice versa |
| Aging (1st year) | Yes — if system spec is ±0.5 ppm/year | Yes — ±1.0 ppm/year acceptable for consumer IoT |
| Voltage control range | ±8 to ±12 ppm at VC=0.5V to 2.5V | Yes — only if PLL tuning range accommodates narrower or wider pull range |
| Phase noise at 1 kHz | Typically -140 dBc/Hz floor | Yes — 3-5 dB worse may still meet less stringent SERDES jitter budgets |
When the RTV-104AF328Y-S-19.200-TR equivalent search yields a candidate with better phase noise but lower temperature stability, prioritize temperature stability for outdoor base stations and phase noise for indoor high-speed serial links. No single parameter dominates — the trade-off matrix is application-specific.
Frequently Asked Questions About RTV-104AF328Y-S-19.200-TR
What is the output swing of the RTV-104AF328Y-S-19.200-TR clipped sine wave?
The clipped sine wave output swing is typically 0.8V p-p when loaded with 10kΩ in parallel with 10pF at 2.8V supply. The DC bias sits at approximately 1.4V (0.5x VDD). Consult the RTV-104AF328Y-S-19.200-TR datasheet for the exact output voltage specification across temperature and supply tolerance.
Can the RTV-104AF328Y-S-19.200-TR be replaced with a 3.3V VCTCXO?
No. The 3.3V supply exceeds the 2.8V absolute maximum rating. An external LDO or resistive divider is needed to drop the supply from 3.3V to 2.8V. Even with regulation, the voltage control input (VC) scaling will shift because its full range is referenced to VDD. Only use a 2.8V VCTCXO or generate the exact rail.
Where can I find the RTV-104AF328Y-S-19.200-TR load capacitance specification?
Load capacitance for the oscillator's internal crystal resonator is not user-accessible — it is fixed inside the package. The "load capacitance" parameter that appears in crystal datasheets does not apply to active oscillators. Instead, refer to the output load specification (10kΩ//10pF typical) which defines the test condition for frequency accuracy and output amplitude.
Does the RTV-104AF328Y-S-19.200-TR have an enable/disable pin?
The standard 4-pad configuration (VC, GND, OUT, VDD) does not include an extra enable pin. If tri-state output control is required, you must add an external load switch on the VDD line. Some alternative VCTCXO packages with the same footprint offer tri-state on pin 1 — verify the substitution's datasheet before use.
For any RTV-104AF328Y-S-19.200-TR cross reference decision, start by measuring your system's startup timing at cold (-40°C) and at 2.8V-5% rail. A VCTCXO that fails startup at low voltage will brick the entire device. Many substitutes that pass nominal characterization fail at the edges — prioritize margin over datasheet promises.
