M41T94_07 Datasheet, PDF (32/41 Pages) STMicroelectronics – Serial real-time clock with 44 bytes NVRAM and reset

DC and AC parameters
Figure 17. Power down/up mode AC waveforms
VCC
VPFD (max)
VPFD (min)
VSO
tF
tFB
tRB
tDR
INPUTS
RECOGNIZED
DON'T CARE
M41T94
tR
tREC
RECOGNIZED
RST
OUTPUTS
VALID
(PER CONTROL INPUT)
HIGH-Z
VALID
(PER CONTROL INPUT)
AI03687
Table 15. Power down/up AC characteristics
Symbol
Parameter⁽¹⁾
Min
Typ
Max Unit
t_F(2)
t_FB(3)
t_R
t_RB
t_REC(4)
t_DR
V_PFD (max) to V_PFD (min) V_CC fall time
V_PFD (min) to V_SS V_CC fall time
V_PFD (min) to V_PFD (max) V_CC rise time
V_SS to V_PFD (min) V_CC rise time
Power up deselect time
Expected data retention time
300
10
10
1
40
10⁽⁵⁾
µs
µs
µs
µs
200
ms
YEARS
1. Valid for ambient operating temperature: T_A = –40 to 85°C; V_CC = 2.7 to 5.5V (except where noted).
2. V_PFD (max) to V_PFD (min) fall time of less than t_F may result in deselection/write protection not occurring
until 200µs after V_CC passes V_PFD (min).
3. V_PFD (min) to V_SS fall time of less than t_FB may cause corruption of RAM data.
4. Programmable (see Table 8 on page 28).
5. At 25°C, V_CC = 0V (when using SOH28 + M4T28-BR12SH SNAPHAT top).
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