Electronic Components Datasheet Search |
|
SP813M Datasheet(PDF) 9 Page - Sipex Corporation |
|
SP813M Datasheet(HTML) 9 Page - Sipex Corporation |
9 / 18 page 9 OCT 17-06 RevB SP705 Low Power Microprocessor Supervisory Circuits © 2006 Sipex Corporation FEATURES The SP705-708/813L/813M series provides four key functions: 1. A reset output during power-up, power-down and brownout conditions. 2. An independent watchdog output that goes LOW if the watchdog input has not been toggled within 1.6 seconds. 3. A 1.25V threshold detector for power-fail warning, low battery detection, or monitoring a power supply other than +5V. 4. An active-LOW manual-reset that allows RESET to be triggered by a pushbutton switch. The SP707/708 devices are the same as the SP705/706 devices except for the active-HIGH RESET substitution of the watchdog timer. The SP813L is the same as the SP705 except an active-HIGH RESET is provided rather than an active-LOW RESET. The SP705/707/813L devices generate a reset when the supply voltage drops below 4.65V. The SP706/708/813M devices generate a reset below 4.40V. The SP705-708/813L/813M series is ideally suited for applications in automotive systems, intelligent instruments, and battery-powered computers and controllers. The SP705-708/813L/ 813M series is ideally applied in environments where monitoring of power supply to a µP and its related components is critical. THEORY OF OPERATION The SP705-708/813L/813M series is a microprocessor ( µP) supervisory circuit that monitors the power supplied to digital circuits such as microprocessors, microcontrollers, or memory. The series is an ideal solution for portable, battery-powered equipment that requires power supply monitoring. Implementing this series will reduce the number of components and overall complexity. The watchdog functions of this product family will continuously oversee the operational status of a system. The operational features and benefits of the SP705-708/813L/ 813M series are described in more detail below. RESET Output A microprocessor's reset input starts the µP in a known state. The SP705-708/813L/813M series asserts reset during power-up and prevents code execution errors during power- down or brownout conditions. On power-up, once V CC reaches 1V, RESET is a guaranteed logic LOW of 0.4V or less. As V CC rises, RESET stays LOW. When V CC rises above the reset threshold, an internal timer re- leases RESET after 200ms. RESET pulses LOW whenever V CC dips below the reset thresh- old, such as in a brownout condition. When a brownout condition occurs in the middle of a previously initiated reset pulse, the pulse con- tinues for at least another 140ms. On power- down, once V CC falls below the reset threshold, RESET stays LOW and is guaranteed to be 0.4V or less until V CC drops below 1V. The SP707/708/813L/813M active-HIGH RESET output is simply the complement of the RESET output and is guaranteed to be valid with V CC down to 1.1V. Some µPs, such as Intel's 80C51, require an active-HIGH reset pulse. Watchdog Timer The SP705/706/813L/813M watchdog circuit monitors the µP's activity. If the µP does not toggle the watchdog input (WDI) within 1.6 seconds and WDI is not tri-stated, WDO goes LOW. As long as RESET is asserted or the WDI input is tri-stated, the watchdog timer will stay cleared and will not count. As soon as RESET is released and WDI is driven HIGH or LOW, the timer will start counting. Pulses as short as 50ns can be detected. |
Similar Part No. - SP813M |
|
Similar Description - SP813M |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | 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 |