ECS-40-20-1 ECS Crystal or Oscillator (Other) In Stock
ECS ECS-40-20-1 is a 4.0000 MHz through-hole quartz crystal with 20 pF load capacitance, providing a stable reference frequency for microcontroller and digital timing circuits. It is housed in a standard HC-49/U through-hole metal package suitable for hand or wave soldering. Widely used in embedded systems, UART clock generation, and real-time clock applications requiring a precise 4 MHz reference.
- Manufacturer
- ECS
- Package
- Other
- Pin Count
- 2
- Lifecycle
- ACTIVE
- Datasheet
- ECS-40-20-1 Datasheet PDF
- Category
- Crystal or Oscillator
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 4.0000 MHz fundamental-mode quartz crystal with 20 pF load capacitance for precision timing in microcontroller clock circuits
- HC-49/U through-hole metal package offering robust mechanical support and easy hand-soldering during prototype and production board assembly
- Stable low-frequency reference suitable for UART baud rate generation, RTC circuits, and 8-bit microcontroller system clocks
Applications
The ECS-40-20-1 provides the 4 MHz clock reference used in 8-bit microcontroller designs such as PIC, AVR, and 8051-based systems where precise UART baud rate timing, timer accuracy, and instruction cycle consistency depend on a stable crystal oscillator. It is also applied in real-time clock circuits, industrial sensor interfaces, and low-speed communication modules where a 4.0000 MHz through-hole crystal offers a cost-effective and reliable frequency source.
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 is specified for the ECS-40-20-1 and why does it matter for oscillator circuit design?
The ECS-40-20-1 is specified with a 20 pF load capacitance, which must be matched by the oscillator circuit's external capacitors to achieve the correct 4.0000 MHz operating frequency. Using capacitors that deviate significantly from 20 pF will shift the crystal's series resonant frequency, causing timing errors in microcontroller UART baud rates, timer counts, and instruction cycles that depend on an accurate 4 MHz reference.
Which microcontroller families commonly use a 4.0000 MHz crystal like the ECS-40-20-1 as their system clock source?
The ECS-40-20-1 is commonly used with 8-bit microcontroller families including PIC (PIC16, PIC18), Atmel AVR (ATmega, ATtiny), and Intel 8051 derivatives that support 4 MHz fundamental-mode crystals with 20 pF load capacitance. At 4 MHz, these microcontrollers execute instructions at rates of 1 MIPS to 4 MIPS depending on the pipeline architecture, making it a standard clock choice for low-power and cost-sensitive embedded control applications.
When is the through-hole HC-49/U package of the ECS-40-20-1 preferred over SMD crystal alternatives in production?
The through-hole HC-49/U package of the ECS-40-20-1 is preferred during prototyping and in low-volume production runs where hand soldering is practical, since it seats securely in a PCB hole without the reflow oven requirements of SMD crystals. It also offers greater mechanical robustness against board flexing and vibration compared to small SMD packages such as the 3.2 mm x 2.5 mm or 5.0 mm x 3.2 mm SMD footprints, making it suitable for industrial and rugged application boards where PCB mechanical stress is a concern.
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