Electronic Components Datasheet Search |
|
AN2595 Datasheet(PDF) 6 Page - STMicroelectronics |
|
AN2595 Datasheet(HTML) 6 Page - STMicroelectronics |
6 / 20 page Oscillator AN2595 - Application note 6/20 1 Oscillator The ST10F27xZx can run with an external clock connected to the XTAL1 input pin of the oscillator inverter or with a clock signal generated by a resonator connected to the XTAL1 / XTAL2 pins. According to the device, two kinds of oscillators have been implemented: ● ST10F276Z5 and ST10F273Z4: wide-swing oscillator (4 to 12 MHz) ● ST10F272Z2 and ST10F271Z1: low-power oscillator (4 to 8 MHz) Moreover, the ST10F27x provides a new feature when the real-time clock (RTC) module is used and a reference clock is needed in Power Down mode. In this case, two possible configurations may be selected by the user application according to the desired level of power reduction: ● A 32 kHz crystal is connected to the on-chip 32 kHz oscillator (pins XTAL3 / XTAL4) and running. In this case, the main oscillator is stopped when Power Down mode is entered, while the real-time clock continues counting using the 32 kHz clock signal as reference. ● Only the main oscillator is running (XTAL1 / XTAL2 pins). In this case, the main oscillator is not stopped when Power Down is entered and the real-time clock continues counting using the main oscillator clock signal as reference. Refer to the ST10F27xZx datasheet for the possible combinations. This chapter provides detailed information on the use of the on-chip oscillator in conjunction with an external resonator. 1.1 Oscillator characteristics Although simple to implement, using an external resonator (crystal or ceramic resonator) requires a few basic precautions. Referring to the schematic of the on-chip oscillator (Figure 1), the key items are described in the following section. Figure 1. Oscillator characteristics The resonator component can be a crystal or a ceramic resonator. It is represented as a series resonant branch Rs, Ls, Cs. The amplification ability of the oscillator inverter is replaced by a negative resistance RL and the capacitance CL contains the C1 and C2 load capacitances and the stray capacitance of the resonator. gm On-chip Oscillator circuit Resonator C1 C2 XTAL1 XTAL2 Cs CL RL Ls Equivalent circuit Rs Resonator |
Similar Part No. - AN2595 |
|
Similar Description - AN2595 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |