M49-25.000-18-30/50/4085 MERCURY Crystal or Oscillator (Other) In Stock
MERCURY M49-25.000-18-30/50/4085 is a 25 MHz fundamental-mode quartz crystal in a 2-pin HC-49-US SMD package with ±30 ppm frequency tolerance and a load capacitance of 18 pF for precise clock generation. It is designed for surface-mount assembly and suits microcontroller, USB, and communication clock applications requiring a stable 25 MHz reference. Available from authorized distributors with worldwide shipping.
- Manufacturer
- MERCURY
- Package
- Other
- Pin Count
- 2
- Lifecycle
- ACTIVE
- Category
- Crystal or Oscillator
- Price
- From $0.3630(MOQ 250)
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 25 MHz fundamental-mode crystal with ±30 ppm frequency tolerance and 18 pF load capacitance for accurate microcontroller and communication clock reference
- Compact 2-pin HC-49-US SMD package enables surface-mount assembly with standard reflow processes, compatible with pick-and-place production
- Operating temperature range of -40°C to +85°C covers standard industrial and commercial grade requirements for 25 MHz clock sources in embedded systems
Applications
The M49-25.000-18-30/50/4085 provides a stable 25 MHz clock reference for microcontrollers, Ethernet PHYs, and USB interface circuits in embedded systems and networking equipment where an accurate frequency source is required. Its ±30 ppm tolerance is suitable for UART baud rate generation, SPI bus clocking, and PHY reference clocks where moderate frequency accuracy is acceptable over the -40°C to +85°C industrial temperature range. The HC-49-US SMD footprint allows direct drop-in replacement of through-hole HC-49-US crystals in redesigned PCBs moving to surface-mount assembly.
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What load capacitance does the M49-25.000-18-30/50/4085 require, and how should it be matched to the oscillator circuit?
The M49-25.000-18-30/50/4085 specifies an 18 pF load capacitance, which must be matched by the external capacitors connected to the crystal's two pins in a Pierce oscillator circuit. Typically, two capacitors of 33 pF to 39 pF from each crystal pin to ground provide the correct effective load of 18 pF when combined with board stray capacitance of about 3 pF to 5 pF, ensuring the crystal oscillates at exactly 25 MHz within the ±30 ppm tolerance.
Over what temperature range does the M49-25.000-18-30/50/4085 maintain its ±30 ppm frequency specification?
The M49-25.000-18-30/50/4085 maintains its ±30 ppm frequency tolerance across an operating temperature range of -40°C to +85°C, covering both commercial and industrial grade ambient conditions. This temperature stability makes it suitable as a 25 MHz reference for Ethernet PHYs, microcontrollers, and USB full-speed clock circuits in industrial control, building automation, and networking equipment deployed in uncontrolled thermal environments.
For a 10/100 Ethernet PHY design, why is the M49-25.000-18-30/50/4085 a practical 25 MHz reference crystal choice?
Most 10/100 Ethernet PHY chips require a 25 MHz fundamental reference crystal with an 18 pF or 20 pF load capacitance and frequency tolerance within ±50 ppm or better. The M49-25.000-18-30/50/4085 meets those requirements with its 25 MHz frequency, 18 pF load, and ±30 ppm tolerance, fitting the 2-pad HC-49-US SMD footprint that appears in the reference schematics of major PHY vendors such as Microchip, Realtek, and Texas Instruments.
Is the HC-49-US SMD package of M49-25.000-18-30/50/4085 compatible with standard reflow soldering, and what peak temperature does it tolerate?
Yes, the HC-49-US SMD package on the M49-25.000-18-30/50/4085 is designed for surface-mount reflow soldering and is compatible with standard lead-free reflow profiles with a peak temperature of up to 260°C for a maximum of 10 seconds, per JEDEC J-STD-020 classification. This allows it to be placed and soldered alongside other SMD components in a single reflow pass without requiring special handling or reduced-temperature profiles.
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About MERCURY
MERCURY is a leading electronic component manufacturer. FindMyChip sources MERCURY ICs directly from authorized China distributors, offering competitive pricing and reliable stock.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 250+ | $0.4100 | $102.50 |
| 1250+ | $0.3800 | $475.00 |
| 2500+ | $0.3630 | $907.50 |
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