5 Crystal Recommendations
Table 5-2 shows a selection of crystals
that have been tested and found suitable for various AVR microcontrollers.
Important: Since many microcontrollers share oscillator modules, only a selection of
representative microcontroller products have been tested by crystal vendors. See the
files distributed with the application note to see the original crystal test reports.
See section Oscillator Module Overview
for an overview of which microcontroller product uses which oscillator
module.
Using crystal-MCU combinations from the table below will ensure good
compatibility and is highly recommended for users with little or limited crystal
expertise. Even though the crystal-MCU combinations are tested by highly experienced
crystal oscillator experts at the various crystal vendors, we still recommend testing your
design as described in Section 3, Testing Crystal Oscillation Robustness, to ensure
that no issues have been introduced during layout, soldering, etc.Table 5-1 shows a list of the different oscillator modules. Section 6, Oscillator Module Overview, has a list of devices where these modules are included.
| # | Oscillator Module | Description |
|---|---|---|
| 1 | X32K_2v7 | 2.7-5.5V oscillator used in megaAVR® devices(1) |
| 2 | X32K_1v8 | 1.8-5.5V oscillator used in megaAVR/tinyAVR® devices(1) |
| 3 | X32K_1v8_ULP | 1.8-3.6V ultra-low power oscillator used in megaAVR/tinyAVR picoPower® devices |
| 4 | X32K_XMEGA (normal mode) | 1.6-3.6V ultra-low power oscillator used in XMEGA® devices. Oscillator configured to normal mode. |
| 5 | X32K_XMEGA (low-power mode) | 1.6-3.6V ultra-low power oscillator used in XMEGA devices. Oscillator configured to low-power mode. |
| 6 | X32K_XRTC32 | 1.6-3.6V ultra-low power RTC oscillator used in XMEGA devices with battery backup |
| 7 | X32K_1v8_5v5_ULP | 1.8-5.5V ultra-low power oscillator used in tinyAVR 0-, 1- and 2-series and megaAVR 0-series devices |
| 8 | OSC_LP_v10 (normal mode) | 1.8-5.5V ultra-low power oscillator used in AVR Dx series devices. Oscillator configured to normal mode. |
| 9 | OSC_LP_v10 (low-power mode) | 1.8-5.5V ultra-low power oscillator used in AVR Dx series devices. Oscillator configured to low-power mode. |
Note:
- Not used with the megaAVR® 0-series or tinyAVR® 0-, 1- and 2-series.
| Vendor | Type | Mount | Oscillator Modules Tested and Approved (See Table 5-1) | Frequency Tolerance [±ppm] | Load Capacitance [pF] | Equivalent Series Resistance (ESR) [kΩ] |
|---|---|---|---|---|---|---|
| Microcrystal | CC7V-T1A | SMD | 1, 2, 3, 4, 5 | 20/100 | 7.0/9.0/12.5 | 50/70 |
| Abracon | ABS06 | SMD | 2 | 20 | 12.5 | 90 |
| Cardinal | CPFB | SMD | 2, 3, 4, 5 | 20 | 12.5 | 50 |
| Cardinal | CTF6 | TH | 2, 3, 4, 5 | 20 | 12.5 | 50 |
| Cardinal | CTF8 | TH | 2, 3, 4, 5 | 20 | 12.5 | 50 |
| Endrich Citizen | CFS206 | TH | 1, 2, 3, 4 | 20 | 12.5 | 35 |
| Endrich Citizen | CM315 | SMD | 1, 2, 3, 4 | 20 | 12.5 | 70 |
| Epson Tyocom | MC-306 | SMD | 1, 2, 3 | 20/50 | 12.5 | 50 |
| Fox | FSXLF | SMD | 2, 3, 4, 5 | 20 | 12.5 | 65 |
| Fox | FX135 | SMD | 2, 3, 4, 5 | 20 | 12.5 | 70 |
| Fox | FX122 | SMD | 2, 3, 4 | 20 | 12.5 | 90 |
| Fox | FSRLF | SMD | 1, 2, 3, 4, 5 | 20 | 12.5 | 50 |
| NDK | NX3215SA | SMD | 1, 2 ,3 | 20 | 12.5 | 80 |
| NDK | NX1610SE | SMD | 1, 2, 4, 5, 6, 7, 8, 9 | 20 | 6 | 50 |
| NDK | NX2012SE | SMD | 1, 2, 4, 5, 6, 8, 9 | 20 | 6 | 50 |
| Seiko Instruments | SSP-T7-FL | SMD | 2, 3, 5 | 20 | 4.4/6/12.5 | 65 |
| Seiko Instruments | SSP-T7-F | SMD | 1, 2, 4, 6, 7, 8, 9 | 20 | 7/12.5 | 65 |
| Seiko Instruments | SC-32S | SMD | 1, 2, 4, 6, 7, 8, 9 | 20 | 7 | 70 |
| Seiko Instruments | SC-32L | SMD | 4 | 20 | 7 | 40 |
| Seiko Instruments | SC-20S | SMD | 1, 2, 4, 6, 7, 8, 9 | 20 | 7 | 70 |
| Seiko Instruments | SC-12S | SMD | 1, 2, 6, 7, 8, 9 | 20 | 7 | 90 |
Note:
- Crystals may be available with multiple load capacitance and frequency tolerance options. Contact the crystal vendor for more information.