Electronic Components Datasheet Search |
|
ADM8691AN Datasheet(PDF) 4 Page - Analog Devices |
|
ADM8691AN Datasheet(HTML) 4 Page - Analog Devices |
4 / 16 page ADM8690–ADM8695 REV. 0 –4– PIN FUNCTION DESCRIPTION Mnemonic Function VCC Power Supply Input: +5 V Nominal. VBATT Backup Battery Input. VOUT Output Voltage, VCC or VBATT is internally switched to VOUT depending on which is at the highest potential. VOUT can supply up to 100 mA to power CMOS RAM. Connect VOUT to VCC if VOUT and VBATT are not used. GND 0 V. Ground reference for all signals. RESET Logic Output. RESET goes low if 1. VCC falls below the Reset Threshold 2. The watchdog timer is not serviced within its timeout period. The reset threshold is typically 4.65 V for the ADM8690/ADM8691/ADM8694/ADM8695 and 4.4 V for the ADM8692 and ADM8693. RESET remains low for 50 ms (ADM8690/ADM8691/ADM8692/ADM8693) or 200 ms (ADM8694/ ADM8695) after VCC returns above the threshold. RESET also goes low for 50 (200) ms if the watchdog timer is enabled but not serviced within its timeout period. The RESET pulse width can be adjusted on the ADM8691/ADM8693/ ADM8695 as shown in Table I. The RESET output has an internal 3 µA pull up, and can either connect to an open collector Reset bus or directly drive a CMOS gate without an external pull-up resistor. WDI Watchdog Input. WDI is a three level input. If WDI remains either high or low for longer than the watchdog timeout period, RESET pulses low and WDO goes low. The timer resets with each transition on the WDI line. The watchdog timer may be disabled if WDI is left floating or is driven to midsupply. PFI Power Fail Input. PFI is the noninverting input to the Power Fail Comparator when PFI is less than 1.3 V, PFO goes low. Connect PFI to GND or VOUT when not used. PFO Power Fail Output. PFO is the output of the Power Fail Comparator. It goes low when PFI is less than 1.3 V. The comparator is turned off and PFO goes low when VCC is below VBATT. CEIN Logic Input. The input to the CE gating circuit. Connect to GND or VOUT if not used. CEOUT Logic Output. CEOUT is a gated version of the CEIN signal. CEOUT tracks CEIN when VCC is above the reset threshold. If VCC is below the reset threshold, CEOUT is forced high. See Figures 5 and 6. BATT ON Logic Output. BATT ON goes high when VOUT is internally switched to the VBATT input. It goes low when VOUT is internally switched to VCC. The output typically sinks 35 mA and can directly drive the base of an external PNP transistor to increase the output current above the 100 mA rating of VOUT. LOW LINE Logic Output. LOW LINE goes low when VCC falls below the reset threshold. It returns high as soon as VCC rises above the reset threshold. RESET Logic Output. RESET is an active high output. It is the inverse of RESET. OSC SEL Logic Oscillator Select Input. When OSC SEL is unconnected (floating) or driven high, the internal oscillator sets the reset active time and watchdog timeout period. When OSC SEL is low, the external oscillator input, OSC IN, is enabled. OSC SEL has a 3 µA internal pull-up (see Table I). OSC IN Oscillator Logic Input. With OSC SEL low, OSC IN can be driven by an external clock signal or an external capacitor can be connected between OSC IN and GND. This sets both the reset active pulse timing and the watch- dog timeout period (see Table I and Figure 4). With OSC SEL high or floating, the internal oscillator is enabled and the reset active time is fixed at 50 ms typ. (ADM8691/ADM8693) or 200 ms typ (ADM8695). In this mode the OSC IN pin selects between fast (100 ms) and slow (1.6 s) watchdog timeout periods. In both modes, the timeout period immediately after a reset is 1.6 s typical. WDO Logic Output. The Watchdog Output, WDO, goes low if WDI remains either high or low for longer than the watchdog timeout period. WDO is set high by the next transition at WDI. If WDI is unconnected or at midsupply, the watchdog timer is disabled and WDO remains high. WDO also goes high when LOW LINE goes low. |
Similar Part No. - ADM8691AN |
|
Similar Description - ADM8691AN |
|
|
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 |