M41T315V-85MH6F STMicroelectronics, M41T315V-85MH6F Datasheet - Page 14

• Manufacturer Part Number: M41T315V-85MH6F
• Description: IC RTC SUPER PHANTOM 85NS 28SOIC
• Manufacturer: STMicroelectronics
• Type: Phantom Time Chipr

Specifications of M41T315V-85MH6F

• Memory Size: 8B
• Time Format: HH:MM:SS (12/24 hr)
• Date Format: YY-MM-DD-dd
• Interface: Serial
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-SOIC, 28-SOH (8.48mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-4703-2

Figure 8.
Note:
2.2
14/30
Comparison register definition
Pattern recognition in “hex” is C5, 3A, A3, 5C, C5, 3A, A3, and 5C. The odds of this pattern
being accidentally duplicated and sending aberrant entries to the RTC is less than 1 in 10
This pattern is sent to the clock LSB to MSB.
Data retention
Most low power SRAMs on the market today can be used with the M41T315Y/V/W. There
are, however some criteria which should be used in making the final choice of an SRAM to
use. The SRAM must be designed in a way where the chip enable input disables all other
inputs to the SRAM. This allows inputs to the M41T315Y/V/W and SRAMs to be Don’t Care
once V
V
with the chip enable output propagation delays included. If the SRAM includes a second
chip enable pin (E2), this pin should be tied to V
If data retention lifetime is a critical parameter for the system, it is important to review the
data retention current specifications for the particular SRAMs being evaluated. Most SRAMs
specify a data retention current at 3.0 volts. Manufacturers generally specify a typical
condition for room temperature along with a worst case condition (generally at elevated
temperatures). The system level requirements will determine the choice of which value to
BYTE 0
BYTE 3
BYTE 6
BYTE 2
BYTE 4
BYTE 5
BYTE 7
BYTE 1
CC
= 2.0 volts. The chip enable access time must be sufficient to meet the system needs
CCI
falls below V
1
0
1
0
1
0
1
0
7
6
1
0
0
1
1
0
0
1
PFD
(min). The SRAM should also guarantee data retention down to
5
0
1
1
0
0
1
1
0
4
0
1
0
1
0
1
0
1
3
0
1
0
1
0
1
0
1
OUT
2
1
0
0
1
1
0
0
1
.
1
0
1
1
0
0
1
1
0
1
0
1
0
0
1
0
1
0
AI04262
Value
Hex
C5
3A
A3
5C
C5
3A
A3
5C
19
.