09/20/00
CS4297A Rev. C Errata
(Reference CS4297A Data Sheet revision DS318PP3 dated Mar `99)
1. When the PC_BEEP bypass is active (RESET# actively asserted and BCFG pin floating) the input impedance for the PC_BEEP input can be lower than the specified minimum of 10 k (approximately 1 k). 2. The CS4297A requires a minimum SYNC pulse width of 1.13 s in the absence of BIT_CLK for a warm reset to occur. AC '97 version 2.1 requires SYNC to be asserted for a minimum of only 1.0 s. Note: This requirement refers to the behavior of SYNC during warm reset only. During normal operation, SYNC is asserted for the entire period of slot 0 (the tag phase) which is 16 cycles of BIT_CLK. 3. SDATA_IN does not meet the AC '97 specification of driving a 47.5 pF capacitive load within the rise time constraints of 2 ns < Trise < 6 ns. However, even at maximum capacitive loading the codec provides sufficient SDATA_IN data setup margin to prevent any functional issues. Workaround Solution- Minimize SDATA_IN trace length during board layout and keep the total capacitive loading to 22 pF or less.
If there are any questions concerning this information, Please contact: Cirrus Logic Audio Technical Support: 1-888-937-2787/ 1-512-912-3555
Cirrus Logic P.O. Box 17847, Austin, Texas 78760 (512) 445 7222 FAX: (512) 445 7581 http://www.cirrus.com
ER318B3 OCT `00 1
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