SPRSP45B March 2020 – December 2020 TMS320F280021 , TMS320F280021-Q1 , TMS320F280023 , TMS320F280023-Q1 , TMS320F280023C , TMS320F280025 , TMS320F280025-Q1 , TMS320F280025C , TMS320F280025C-Q1
PRODUCTION DATA
When using a quartz crystal, it may be necessary to include a damping resistor (RD) in the crystal circuit to prevent overdriving the crystal (drive level can be found in the crystal data sheet). In higher-frequency applications (10 MHz or greater), RD is generally not required. If a damping resistor is required, RD should be as small as possible because the size of the resistance affects start-up time (smaller RD = faster start-up time). TI recommends that the crystal manufacturer characterize the crystal with the application board. Section 7.11.3.4.1 lists the crystal oscillator parameters. Table 7-3 lists the crystal equivalent series resistance (ESR) requirements. Section 7.11.3.4.2 lists the crystal oscillator electrical characteristics.