Datasheet

M41T81S DC and AC parameters
Doc ID 10773 Rev 7 25/32
Table 9. DC characteristics
Table 10. Crystal electrical characteristics
Figure 16. Power down/up mode AC waveforms
Sym Parameter Test condition
(1)
1. Valid for ambient operating temperature: T
A
= –40 to 85 °C; V
CC
= 2.7 to 5.5 V (except where noted).
Min Typ Max Unit
I
LI
Input leakage current 0 V ≤ V
IN
≤ V
CC
±1 µA
I
LO
Output leakage current 0 V ≤ V
OUT
≤ V
CC
±1 µA
I
CC1
Supply current Switch freq = 400 kHz 400 µA
I
CC2
Supply current (standby)
SCL = 0 Hz
All inputs
≥ V
CC
– 0.2 V
≤ V
SS
+ 0.2 V
100 µA
V
IL
Input low voltage –0.3 0.3V
CC
V
V
IH
Input high voltage 0.7V
CC
V
CC
+
0.3
V
V
OL
Output low voltage I
OL
= 3.0 mA 0.4 V
Output low voltage
(open drain)
(2)
2. For IRQ/FT/OUT/SQW pin (open drain)
I
OL
= 10 mA 0.4 V
Pull-up supply voltage
(open drain)
IRQ
/OUT/FT/SQW 5.5 V
V
BAT
(3)
3. STMicroelectronics recommends the RAYOVAC BR1225 or BR1632 (or equivalent) as the battery supply.
Backup supply voltage 2.0 3.5
(4)
4. For rechargeable back-up, V
BAT
(max) may be considered to be V
CC
.
V
I
BAT
Battery supply current
T
A
= 25 °C, V
CC
= 0 V
Oscillator ON, V
BAT
= 3 V
0.6 1 µA
Sym Parameter
(1)and(2)
1. Externally supplied if using the SO8 package. 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.
2. Load capacitors are integrated within the M41T81S. Circuit board layout considerations for the 32.768 kHz
crystal of minimum trace lengths and isolation from RF generating signals should be taken into account.
Min Typ Max Units
f
O
Resonant frequency - 32.768 kHz
R
S
Series resistance - 60
(3)
3. For applications requiring back-up supply operation below 2.5 V, R
S
(max) should be considered 40 kΩ.
kΩ
C
L
Load capacitance - 12.5 pF
AI00596
V
CC
trec
tPD
V
SO
SDA
SCL
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