Precaution for use the crystal unit with low CL
1. Note
A crystal unit with low CL is very sensitive to load capacitance variations of the oscillation circuit, so the environment the crystal is operated in. (*1)
Consequently, the tolerance of the oscillation frequency in the actual circuit will exceed the tolerance defined in the crystal specification significantly.
2. Products
1) For STMicroelectronics
Target MCU: STM32F401
Epson 32kHz crystal unit
| Name | CL [pF] |
Part number | Pulling Sensitivity*[ppm/pF] | Deviation max* [sec/pF] |
|---|---|---|---|---|
| FC-135R | 6.0 | X1A0001410006 | 34 | 88 |
| FC-12M | 5.0 | X1A0000610018 | 81 | 210 |
| FC1610AN |
5.0 | TBD | TBD | TBD |
* : absolute value
2) For NXP Semiconductors
Target RTC Module: PCF85263
Epson 32kHz crystal unit
| Name | CL [pF] |
Part number | Pulling Sensitivity*[ppm/pF] | Deviation max* [sec/pF] |
|---|---|---|---|---|
| FC-135R | 6.0 | X1A0001410006 | 34 | 88 |
| FC-135 | 6.0 | Q13FC13500018 | 35 | 91 |
| MC-146 | 6.0 | Q13MC14620006 | 47 | 122 |
Epson 32kHz crystal unit
| Name | CL [pF] |
Part number | Pulling Sensitivity*[ppm/pF] | Deviation max* [sec/pF] |
|---|---|---|---|---|
| FC-135R | 6.0 | X1A0001410006 | 34 | 88 |
* : absolute value
3) For Texas Instruments
Target MCU: MSP430FR5969
Epson 32kHz crystal unit
| Name | CL [pF] |
Part number | Pulling Sensitivity*[ppm/pF] | Deviation max* [sec/pF] |
|---|---|---|---|---|
| MC-146L | 3.7 | X1A0001520001 | 47 | 122 |
* : absolute value
4) For Renesas Electronics
Target MCU: RX200, RX600, RX700 Series
Epson 32kHz crystal unit
| Name | CL [pF] |
Part number | Pulling Sensitivity*[ppm/pF] | Deviation max* [sec/pF] |
|---|---|---|---|---|
| MC-146L | 3.7 | X1A0001520001 | 47 | 122 |
* : absolute value
3. Notes
CL=5.0[pF] and 6.0[pF] are not our standard specification so if you will use them please contact our sales person.
We would like to check about specification in our company.