FM31272 View Datasheet(PDF) - Ramtron International Corporation
Part Name
Description
MFG CO.
'FM31272' PDF : 26 Pages View PDF
FM31278/276/274/272 - 5V I2C Companion
DC Operating Conditions, continued (TA = -40° C to + 85° C, VDD = 4.0V to 5.5V unless otherwise specified)
Symbol Parameter
Min
Typ
Max
Units Notes
RIN
VPFI
VHYS
Input Resistance (pulldown)
A1-A0 for VIN = VIL max
A1-A0 for VIN = VIH min
Power Fail Input Reference Voltage
Power Fail Input (PFI) Hysteresis (Rising)
20
1
1.175
1.20
-
KΩ
MΩ
1.225
V
100
mV
Notes
1. SCL toggling between VDD-0.3V and VSS, other inputs VSS or VDD-0.3V.
2. All inputs at VSS or VDD, static. Stop command issued.
3. VIN or VOUT = VSS to VDD. Does not apply to A0, A1, or /RST pins.
4. VBAK = 3.0V, VDD < 2.4V, oscillator running, CNT1-2 at VBAK.
5. /RST is asserted low when VDD < VTP.
6. The minimum VDD to guarantee the level of /RST remains a valid VOL level.
7. Full complete operation. Supervisory circuits, RTC, etc operate to lower voltages as specified.
8. Includes /RST input detection of external reset condition to trigger driving of /RST signal by FM3127x.
9. The VBAK trickle charger automatically regulates the maximum voltage on this pin for capacitor backup applications.
10. VBAK will source current when trickle charge is enabled (VBC bit=1), VDD > VBAK, and VBAK < VBAK max.
AC Parameters (TA = -40° C to + 85° C, VDD = 4.0V to 5.5V, CL = 100 pF unless otherwise specified)
Symbol Parameter
Min Max Min Max Min Max
fSCL
tLOW
tHIGH
tAA
SCL Clock Frequency
Clock Low Period
Clock High Period
SCL Low to SDA Data Out Valid
0 100 0 400 0 1000
4.7
1.3
0.6
4.0
0.6
0.4
3
0.9
0.55
tBUF
Bus Free Before New Transmission 4.7
tHD:STA Start Condition Hold Time
4.0
tSU:STA Start Condition Setup for Repeated 4.7
Start
1.3
0.5
0.6
0.25
0.6
0.25
tHD:DAT Data In Hold Time
0
0
0
tSU:DAT Data In Setup Time
250
100
100
tR
Input Rise Time
1000
300
300
tF
Input Fall Time
300
300
100
tSU:STO Stop Condition Setup Time
4.0
0.6
0.25
tDH
Data Output Hold (from SCL @ VIL) 0
0
0
tSP
Noise Suppression Time Constant
50
50
50
on SCL, SDA
All SCL specifications as well as start and stop conditions apply to both read and write operations.
Units
kHz
µs
µs
µs
µs
µs
µs
ns
ns
ns
ns
µs
ns
ns
Notes
1
1
Capacitance (TA = 25° C, f=1.0 MHz, VDD = 5.0V)
Symbol
Parameter
CIO
CXTAL
Input/Output Capacitance
X1, X2 Crystal pin Capacitance
Notes
1 This parameter is characterized but not tested.
2 The crystal attached to the X1/X2 pins must be rated as 12.5pF.
Data Retention (TA = -40° C to + 85° C, VDD = 4.0V to 5.5V)
Parameter
Data Retention
Typ
Max
Units
-
8
pF
25
-
pF
Min
Units
Notes
10
Years
Notes
1
1, 2
Rev. 2.0
Dec. 2007
Page 21 of 25
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