MCP795WXX/MCP795BXX
SPI Real-Time Clock Calendar with
Enhanced Features and Battery Switchover
Device Selection Table
Part Number
MCP795W20
MCP795W10
MCP795W21
MCP795W11
MCP795W22
MCP795W12
MCP795B20
MCP795B10
MCP795B21
MCP795B11
MCP795B22
MCP795B12
Note:
32 kHz
Boot-up
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
SRAM
(Bytes)
64
64
64
64
64
64
64
64
64
64
64
64
EEPROM
(Kbits)
2
1
2
1
2
1
2
1
2
1
2
1
Unique
ID
Blank
Blank
EUI-48
™
EUI-48
™
EUI-64
™
EUI-64
™
Blank
Blank
EUI-48
™
EUI-48
™
User Memory:
• 64-Byte Battery-Backed SRAM
• 2 Kbit and 1 Kbit EEPROM Memory:
- Software block write-protect (¼, ½, or entire
array)
- Write Page mode (up to 8 bytes)
- Endurance: 1M erase/write cycles
• 128-Bit Unique ID in Protected Area of EEPROM:
- Available blank or preprogrammed
- EUI-48™ or EUI-64™ MAC address
- Unlock sequence for user programming
Enhanced Features:
• SPI Clock Speed up to 10 MHz
• Programmable Watchdog Timer:
- Dedicated watchdog output pin
- Dual retrigger using SPI bus or EVHS digital
input
• Dual Configurable Event Detect Inputs:
- High-Speed Digital Event Detect (EVHS) with
pulse count for 1
st
, 4
th
,16
th
or 32
nd
event
- Low-Speed Event Detect (EVLS) with
programmable debounce delays of 31 msec
and 500 msec
- Edge triggered (rising or falling)
- Operates from V
CC
or V
BAT
• Operating Temperature Ranges:
- Industrial (I Temp): -40°C to +85°C.
• Packages include 14-Lead SOIC and TSSOP
SOIC/TSSOP
X1
X2
V
BAT
WDO
IRQ
CS
V
SS
1
14
Vcc
CLKOUT/BOOT
EVHS
EVLS
SCK
SI
SO
EUI-64
™
EUI-64
™
Watchdog Timer and Event Detects in all devices.
Timekeeping Features:
• Real-Time Clock/Calendar:
- Hours, Minutes, Seconds, Hundredth of
Seconds, Day of Week, Month, Year, Leap
Year
• Crystal Oscillator requires External 32,768 kHz
Tuning Fork Crystal and Load Capacitors.
• Clock Out Function:
- 1Hz, 4.096 kHz, 8.192 kHz, 32.768 kHz
• 32 kHz Boot-up Clock at Power-up (MCP795BXX)
• 2 Programmable Alarms – Supports IRQ or WDO
• Programmable open drain output – Alarm or
Interrupt
• On-Chip Digital Trimming/Calibration:
- +/- 255 PPM range in 1 PPM steps
• Power-Fail Time-Stamp @ Battery Switchover:
- Logs time when V
CC
fails and V
CC
is restored
MCP795XXX
2
3
4
5
6
7
13
12
11
10
9
8
Low-Power Features:
• Wide Operating Voltage:
- V
CC
: 1.8V to 5.5V
- V
BAT
: 1.3V to 5.5V
• Low Operating Current:
- V
CC
Standby Current < 1uA @ 3V
- V
BAT
Timekeeping Current: <700nA @ 1.8V
• Automatic Battery Switchover from V
CC
to V
BAT
:
- Backup power for timekeeping and SRAM
retention
Note:
MCP795XXX is used in this document as a
generic part number for the MCP795WXX,
MCP795BXX devices.
2011 Microchip Technology Inc.
Preliminary
DS22280A-page 1
MAS [ MICRO ANALOG SYSTEMS ]
