Motore di ricerca datesheet componenti elettronici |
|
CBC-EVAL-12-34813 Scheda tecnica(PDF) 6 Page - Cymbet Corporation |
|
CBC-EVAL-12-34813 Scheda tecnica(HTML) 6 Page - Cymbet Corporation |
6 / 9 page CBC34813 EnerChip™ RTC ©2013 Cymbet Corporation • Tel: +1-763-633-1780 • www.cymbet.com DS-72-38 V.01 Page 6 of 9 Preliminary CBC34813(AM0813)RegisterDefinitions(00to0F) The following register bits must be set prior to any switchover, even from VDD to the EnerChip. BREF bits: The default value out of reset is 0000. This needs to be reprogrammed to 1111. IOBM bit: The default value out of reset is 1. This needs to be reprogrammed to 0. Crystal Oscillator Selection The AM0813 should work with any standard 32.768kHz tuning fork crystal with a load capacitance rating from 0 - 12pF and an ESR from 0 - 90kohms. Recommendations are as follows: • Crystal load capacitance rating: 0 - 12pF • Crystal ESR rating: 0 – 90kohms max • No additional loading capacitors on the board • Stray PCB capacitance on XO/XI: 2pF or less (less is better) Typically, an oscillator allowance (OA) of 260-290kohms is generated. Increasing the loading capacitance on the XI/XO pins will decrease the OA and using crystals with a higher ESR will reduce the OA margin. The crystal will not affect the AM0813 RTC current because a fixed bias current to the crystal is used. No external load capacitance is required because the frequency offset from the crystal is digitally calibrated out, to within +/- 2ppm. Mainstream crystals (3.2mm x 1.5mm) generally have a maximum ESR rating of 70kohms. The smaller 2.0mm x 1.2mm crystals generally have a maximum ESR of 90kohms. Some crystal vendors, such as Epson or Micro Crystal, might have some of the smaller crystals with lower ESR. Below is a list of crystals from several vendors that have been tested: Abracon: ABS07-32.768KHZ-7-T, ABS06-32.768KHZ-9-T, ABS25.32.768KHZ-T Epson: C-002RX, FC-135, FC-12D, FC-12M Micro Crystal: CC7V-T1A, CM7V-T1A |
Codice articolo simile - CBC-EVAL-12-34813 |
|
Descrizione simile - CBC-EVAL-12-34813 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEETIT.COM |
Lei ha avuto il aiuto da alldatasheet? [ DONATE ] |
Di alldatasheet | Richest di pubblicita | contatti | Privacy Policy | scambio Link | Ricerca produttore All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |