MCP79510 MAS [Micro Analog systems], MCP79510 Datasheet - Page 28

• Manufacturer Part Number: MCP79510
• Description: 3V SPI Real-Time Clock Calendar with Battery Switchover
• Manufacturer: MAS [Micro Analog systems]

MCP7952X/MCP7951X
9.1.2
Pin 9 is a multifunction pin and supports the following
functions:
• The value of the OUT bit determines the logic.
• Level of the I/O. This is only available when
• Alarm Outputs – Available in V
• F
The internal control logic for the MFP is connected to
the switched internal supply bus. This allows operation
in V
operates in V
9.1.3
If the V
connected to GND. A low value series resistor and
Schottky diode are recommended between the
external battery and the V
current and also to prevent any leakage current
reaching the external V
The V
falls below 1.5V the system will continue to operate
the RTCC and SRAM using the V
~50mV hyst in the trip point changeover. The following
conditions apply:
FIGURE 9-2:
To write to the unique ID locations, the IDWRITE com-
mand is used. The device must be write enabled and
the correct unlock sequence must have been per-
formed. See
Register
DS22300A-page 28
operating from V
available in V
OUT
BAT
SCK
Address range is 0x00-0x0F, address counter will wrap within this range.
CS
SO
TRIP
SI
BAT
mode. The Alarm Output is the only mode that
mode – Driven from a FOSC divider – Not
for more details.
point is defined as 1.5V typical. When V
feature is not used, the V
MULTIFUNCTION PIN (MFP)
V
BAT
BAT
0
0
Section 10.1.4, Write to the Unlock
BAT
mode, other modes are suspended.
0
SWITCHOVER
1
CC
mode.
1
.
2
Instruction
IDREAD COMMAND SEQUENCE
BAT
1
3
source.
BAT
0
4
BAT
pin to reduce inrush
0
BAT
5
High-Impedance
BAT
mode
1
6
supply. There is
pin should be
1
7
0
8
0
9 10 11 12 13 14 15 16 17 18 19 20 21 22
Preliminary
DD
0
Address Byte
0
3
TABLE 9-1:
For more information on V
Best Practices Application Note, AN1365 (DS01365).
9.1.4
When the unique ID locations are preprogrammed from
the factory with either an EUI-48 or EUI-64, the EUI
code is programmed into location 0x00-0x07. Loca-
tions 0x08-0x0F are blank (0x0F).
To read the unique ID location the IDREAD command
is given with the starting address. Valid addresses are
0x00 through 0x0F. All 16 bytes can be read out in a
single command by clocking the device. Trying to
access locations past 0x0F will result in the address
wrapping within these 16 bytes.
The ID locations can be written to using the IDWRITE
command. The valid address is between 0x00 and
0x0F. The entire 16 bytes must be written in two
groups of 8 bytes. A maximum of 8 bytes can be
written at once.
V
V
V
2
CC
CC
CC
Note:
< V
> V
> V
1 0
Condition
TRIP
TRIP
TRIP
Supply
UNIQUE ID LOCATIONS
For EUI-64, the data is located in address
0x00-0x07. For EUI-48 locations, 0x02-
0x07 contain the data. 0x00/01 contain
0xFF.
, V
, V
, V
7
CC
CC
CC
6
V
CONDITIONS
< V
< V
> V
BAT
5
BAT
BAT
BAT
Don’t Care
 2012 Microchip Technology Inc.
Data Out
CHANGOVER
BAT
4
Read/Write
conditions see the RTCC
3
Access
Yes
Yes
No
2
1
0
23
Powered
V
V
V
By
BAT
CC
CC