| công cụ tìm kiếm bảng dữ liệu linh kiện điện tử |
|
EM3027IDSWS8 bảng dữ liệu(PDF) 8 Page - EM Microelectronic - MARIN SA |
|
|
|||||||||||||||||||||||||||||
EM3027IDSWS8 bảng dữ liệu(HTML) 8 Page - EM Microelectronic - MARIN SA |
|
8 / 28 page ![]() EM3027 Copyright 2013, EM Microelectronic-Marin SA 3027-DS.doc, Version 8.0, 25-Jan-13 8 www.emmicroelectronic.com 4.4 Crystal Calibration In order to compensate temperature dependency of the used crystal, correct values of XtalOffset, Qcoef and TO parameters shall be stored in EEPROM Control Page. User is advised to follow these steps in order to compute the parameters in a correct way: 1) Supply the chip from VCC pin. 2) Set FD0 = FD1 = ‘0’. Set CLKOE pin to ’1’. This provides the uncompensated frequency signal from the crystal oscillator directly on pin CLKOUT. 3) Measure output frequency fO at different temperatures (at least five measurements in equidistant points in the whole desired temperature range are recommended). Please note that quartz crystal needs few minutes to stabilise its frequency at a given temperature. 4) Compute frequency deviation ferr in ppm of output frequency fo from the ideal (target) frequency fL = 32.768Hz in all measured points as follows: ferr = 10 6(f o-fL)/fL . 5) Find a quadratic regression of the measured dependency in form: ferr = -c1(T – c2) 2 + c 3 or fO = aT 2 + bT + c. 6) Then real values of the searched parameters can be obtained from the following relations: Qcoefreal = c1 = -a, T0_real = c2 = -b/(2a), XtalOffsetreal = c3 = c – b 2/(4a). 7) The values to be stored in EEPROM Control Page have to be corrected in the following way: Qcoef = 4096*(1.05*Qcoefreal), T0 = T0_real - 4, XtalOffset = 1.05*XtalOffsetreal. |
|
Link URL |
| Cho đến nay ALLDATASHEET có giúp ích cho doanh nghiệp của bạn hay không? [ DONATE ] |
Alldatasheet là | Quảng cáo | Liên lạc với chúng tôi | Chính sách bảo mật | Liên kết đến bảng dữ liệu | Trao đổi link | Tìm kiếm theo nhà sản xuất 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 |