m41t81 STMicroelectronics, m41t81 Datasheet - Page 23

• Manufacturer Part Number: m41t81
• Description: Serial Access Real-time Clock With Alarms
• Manufacturer: STMicroelectronics

M41T81
Table 9.
1.
2.
3.
4.
5.
Table 10.
1.
2.
Figure 15. Power down/up mode AC waveforms
V
Sym
I
I
BAT
I
V
I
CC1
CC2
V
V
BAT
I
Valid for Ambient Operating Temperature: T
For IRQ/FT/OUT/SQW pin (Open Drain)
STMicroelectronics recommends the RAYOVAC BR1225 or BR1632 (or equivalent) as the battery supply.
After switchover (V
For rechargeable back-up, V
Externally supplied. STMicroelectronics recommends the KDS DT-38: 1TA/1TC252E127, Tuning Fork Type (thru-hole) or the DMX-26S:
1TJS125FH2A212, (SMD) quartz crystal for industrial temperature operations. KDS can be contacted at [e-mail] or
http://www.kdsj.co.jp for further information on this crystal type.
Load capacitors are integrated within the M41T81. Circuit board layout considerations for the 32.768kHz crystal of minimum trace lengths and
isolation from RF generating signals should be taken into account.
LO
LI
OL
Sym
IH
IL
V CC
V SO
SDA
SCL
R
C
f
(3)
O
S
L
Input leakage current
Output leakage current
Supply current
Supply current (standby)
Input low voltage
Input high voltage
Output low voltage
Output low voltage (open
drain)
Pull-up supply voltage
(open drain)
Battery supply voltage
Battery supply current
Resonant frequency
Series resistance
Load capacitance
DC characteristics
Crystal electrical characteristics
(2)
tPD
SO
Parameter
), V
BAT
BAT
Parameter
(min) can be 2.0V for crystal with R
(max) may be considered V
A
(1) (2)
= –40 to 85°C; V
SCL,SDA = V
oscillator on, V
Switch freq = 400kHz
T
IRQ/OUT/FT/SQW
A
Test condition
0V ≤ V
CC
= 25°C, V
0V ≤ V
CC
.
I
I
OL
DON'T CARE
S
OL
= 2.0 to 5.5V (except where noted).
= 40KΩ.
= 3.0mA
= 10mA
OUT
IN
Min
CC
≤ V
CC
BAT
≤ V
CC
– 0.3V
= 0V
CC
(1)
= 3V
32.768
12.5
Typ
0.7V
2.5
–0.3
Min
(4)
CC
DC and AC parameters
Typ
0.6
3
Max
60
V
trec
0.3V
CC
3.5
Max
400
100
0.4
0.4
5.5
±1
±1
1
+ 0.3
(5)
CC
AI00596
Units
kHz
pF
kΩ
23/30
Unit
µA
µA
µA
µA
µA
V
V
V
V
V
V