For customer designing Renesas Electronics MCU UPD78F8058, M16C/6B series ZigBee/IEEE802.15.4 applications
The following provides a basic explanation of design considerations for the external oscillation circuit using quartz crystal for 'Low Power RF' technology including ZigBee,IEEE802.15.4 and sub 1 GHz band wireless applications.
"Please refer to Renesas Electronics ZigBee/IEEE802.15.4 solution below."
Items to Confirm (designing of oscillation circuit)
Please refer to Renesas Electronics official site for additional information.
In realizing low power consumption RF designs, the following factors should be taken into consideration.
- Oscillation start-up time
- Frequency tuning
- Lower BER(Bit Error Rate) over operating temperature
| No. | Oscillation Circuit Factor | 2.4 GHz |
| < AT crystal unit spec.> | ||
| 1 | Quick oscillation start-up time *High oscillation allowance *Boost inverter |
*Lower ESR(R1) *High drive level |
| 2 | Easy frequency control *inner frequency tuning capacitor |
*proper frequency sensitivity *low parameters' variation |
| 3 | Lower BER *temperature compensation |
*High frequency stability |
| MHz Crystal equivalent circuit |
 |
| Rapid Oscillation start-up time
-> Lower ESR (R1) , Higher C1 -> Higher drive level |
 |
| Suitable Frequency Tuning -> Lower parameters variation(C0,C1,L1,ESR) |
 |
| Suitable Frequency Tuning-> Proper Sensitivity (CL,C0) |
 |
| Higher Frequency Stability-> Stable fSTA |
 |
Clock solution recommendations for Renesas Electronics UPD78F8058, M16C/6B series
| Worldwide | UPD78F8058 | M16C/6B | ||||
| US | Europe | Japan | Asia | |||
| ZigBee IEEE802.15.4 |
2400 to 2483.5 MHz | |||||
| Recommendable Clock Devices |
TSX-3225
32 MHz 8 pF (X1E000021049300) FA-20H 32 MHz 8 pF |
FA-20H 16
MHz 12 pF Q24FA20H00232** TSX-3225 16 MHz 12 pF |
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Notes:
Above recommendations are based on actual evaluation results and intended to support users in picking the right components. And the results are only according to the sample set that received from our customers, so it is not including the dispersion trend of IC and the external parts.
As the actual board layout and choice of external components influences the best suitable crystal load capacitance, We do not assume any responsibility and grant warranty for above recommendations.
Users design must be verified and decided by own and individual evaluation.
*ZigBee is a registered trademark of Koninklijke Philips Electronics N.V.