ST M48T58, M48T58Y User Manual

查询M48T58Y-70MH1供应商

5.0V, 64 Kbit (8 Kb x 8) TIMEKEEPER®SRAM

FEATURES SUMMARY

■ INTEGRATED, ULTRA LOW POWER SRAM,

REAL TIMECLOCK, POWER-FAILCONTROL
CIRCUIT and BATTERY

■ BYTEWIDE™ RAM-LIKE CLO CK A CCESS

■ BCD CODED YEAR, MONTH, DAY, DATE,

HOURS, MINUTES, and SE CONDS

■ FREQUENCY TEST OUTPUT FOR REAL

TIME CLOCK

■ AUTOMATIC POWER-FAIL CHIP DESELECT

and WRITE PROTECTION

■ WRITE PROTECT VOLTAGES

(V

= Power-fail Deselect V oltage):

PFD

– M48T58: V

4.5V ≤ V

– M48T58Y: V

4.2V ≤ V

■ SELF-CONTAINED BATTERY and CRYSTAL

IN THE CAPHAT™ DIP PACKAGE

■ PACKAGINGINCLUDESa28-LEADSOICand

SNAPHAT

■ SOIC PACKAGE PROVIDES DIRECT

CONNECTION FOR A SNAPHAT HOUSING
CONTAINING THE BATTERY and CRYSTAL

■ PIN and FUNCTION COMPATIBLE WITH

JEDEC STANDARD 8 Kb x 8 SRAMs

= 4.75 to 5.5V

CC

≤ 4.75V

PFD

= 4.5 to 5.5V

CC

≤ 4.5V

PFD

®

TOP (to be Ordered Separately)

M48T58

M48T58Y

Figure 1. 28-pin P CDI P, CAPHAT™ Package

28

1

PCDIP28 (PC)
Battery/Crystal

CAPHAT

Figure 2. 28-pin SOIC Package

SNAPHAT (SH)

Battery/Crystal

28

SOH28 (MH)

1

1/27May 2002

M48T58, M48T58Y

TABLE OF CONTENTS

SUMMARYDESCRIPTION...........................................................4

LogicDiagram(Figure3.).........................................................4

SignalNames(Table1.)..........................................................4

DIP Connect ions (Figure 4.) .......................................................5

SOIC Connections (Fig ure 5.)......................................................5

BlockDiagram(Figure6.).........................................................5

MAXIMUMRATING.................................................................6

AbsoluteMaximumRatings(Table2.) ...............................................6

DC AND AC PARAMETERS. . ........................................................7

Operating and AC Measurement Conditions (Tabl e 3.) ..................................7

ACMeasurementLoadCircuit(Figure7.).............................................7

Capacitance (Table 4. ) . . . ........................................................7

DCCharacteristics(Table5.) ......................................................8

OPERATIONMODES...............................................................9

Operating Modes (Table 6.)........................................................9

READMode...................................................................10

READModeACWaveforms(Figure8.).............................................10

READModeACCharacteristics(Table7.)...........................................11

WRITEMode..................................................................12

WRITE Enable Controlled, WRITE AC Waveform (Figure 9.).............................12

ChipEnableControlled,WRITEACWaveforms(Figure10.).............................13

WRITEModeACCharacteristics(Table8.)..........................................14

DataRetentionMode............................................................15

PowerDown/UpModeACWaveforms(Figure11.)....................................15

PowerDown/UpACCharacteristics(Table9.)........................................16

PowerDown/UpTripPointsDCCharacteristics(Table10.)..............................16

2/27

M48T58, M 48T 58Y

CLOCKOPERATIONS.............................................................17

Reading the Clock. .............................................................17

RegisterMap(Table11.).........................................................17

SettingtheClock...............................................................17

Stopping and S tarting the Oscillator ................................................17

CalibratingtheClock............................................................18

BatteryLowFlag...............................................................19

CenturyBit....................................................................19

CrystalAccuracyAcrossTemperature(Figure12.) ....................................19

ClockCalibration(Figure13.).....................................................20

V

Noise And Negative Going Transients. ..........................................20

CC

SupplyVoltageProtection(Figure14.)..............................................20

PARTNUMBERING ...............................................................21

SNAPHATBatteryTable(Table13.)................................................21

PACKAGE MECHANICAL INFORMATION . . . ..........................................22

REVISIONHISTORY...............................................................26

3/27

M48T58, M48T58Y

SUMMARY DESCRIPTION

®

The M48T58/Y TIMEKEEPER
non-volatile static RAM and real time clock . The
monolithic chip is available in two special pack ag­esto providea highly integrated battery backed-up
memory and real time clock solution.

The M48T58 /Y is a non-volatile pin and func tion
equivalent toany JEDEC s tandard 8Kbx 8 SR AM.
It also easily fits into many ROM, EPROM, and
EEPROM sockets, providing the non-volatility of
PROMs without any requirement for special
WRITE timing or limitations on the number of
WRITEs that can be performed.

The 28-pin, 600mil DIP CAPHAT™ houses the
M48T58/Y silicon with a quartz crystal and a long
life lithium button cell in a single package.

RAM is a 8Kb x 8

The 28-pin, 330mil SOIC provides sockets with
gold plated contacts at both ends for direct con­nection to a separate SNAPHAT
taining the battery and crystal. The unique design
allows the SNAPHAT battery pac k age to be
mounted on top of the SOIC package after the
completion of the surface mount process. Inser­tion of the SNAPHAT housing after reflow pre­vents potential battery and crystal damage due to
the high temperatures required for device surface­mounting. The S NAPHAT housing is keyed to pre­vent rev ers e insertion. The S OI C and battery/crys­tal packages are shipped separatelyin plastic anti­static tubes or in Tape & Reel form.

For the 28-lead SOIC, the battery/crystal package
(e.g., SNAPHAT) part number is “M4T 28­BR12SH” (see Table 13, page 21).

Figure 3. Logic Diagram Table 1. Signal Names

A0-A12 Address Inputs

DQ0-DQ7 Data Inputs / Outputs

FT

Frequency Test Output (Open
Drain)

A0-A12

13

V

CC

8

DQ0-DQ7

®

housing con-

W

E1 FT

E2

G

M48T58

M48T58Y

V

SS

AI01374B

E1
E2 Chip Enable 2

G

W

V

CC

V

SS

Chip Enable 1

Output Enable
WRITE Enable
Supply Voltage
Ground

4/27

M48T58, M 48T 58Y

Figure 4. DIP Connections Figure 5. SOIC Connections

FT V

1

A12

2

A7

3

A6

4

A5

5
6

A4

7

A3
A2
A1
A0

DQ0

8

M48T58Y
9
10
11

M48T58

12

DQ2

13
14

SS

Figure 6. Block Diagram

32,768 Hz
CRYSTAL

28

CC

W

27
26

E2

25

A8

24

A9

23

A11

22

G

21

A10

20

E1

19

DQ7

18

DQ6

17

DQ5DQ1
DQ4

16

DQ3V

15

AI01375B

FT

OSCILLATOR AND

CLOCK CHAIN

FT V

A12

A7
A6
A5
A4
A3
A2
A1
A0

DQ0

1
2
3
4
5
6
7
8
9
10
11

M48T58Y

12

DQ2

SS

13
14

8 x 8 BiPORT

SRAM ARRAY

28
27
26
25
24
23
22
21
20
19
18
17
16
15

AI01376B

CC

W
E2
A8
A9
A11
G
A10
E1
DQ7
DQ6
DQ5DQ1
DQ4
DQ3V

A0-A12

LITHIUM

CELL

VOLTAGE SENSE

AND

SWITCHING

CIRCUITRY

V

CC

POWER

V

PFD

8184 x 8

SRAM ARRAY

V

SS

DQ0-DQ7

E1
E2
W
G

AI01377C

5/27

M48T58, M48T58Y

MAXIMUM RATING

Stressingthedeviceabovetheratinglistedinthe
“Absolute Maxim um Ratings” table may cause
permanent damage to the dev ice. These are
stress ratings only and operation of the device at
these or any other conditions a bove those indicat­ed in the Operating sections of this specification is

Table 2. Absolute Maximum Ratings

Symbol Parameter Value Unit

T

A

T

STG

(1,2)

T

SLD

V

IO

V

CC

I

O

P

D

Note: 1. For DIP package: Soldering temperature not to exceed 260°C for 10 seconds (total thermal budget not to exceed 150°C for longer

than 30 seconds).

2. For SO package: Reflow at peak temperature of 215°C to 225°C for < 60 seconds (total thermal budget not to exceed 180°C for
between 90 to 120 seconds).

CAUTION: Negative undershoots below –0.3V are not allowed on any pin while in the Battery Back-up mode.
CAUTION: Do NOT wave solder SOICto avoid damaging SNAPHAT sockets.

Ambient Operating Temperature 0 to 70 °C
Storage Temperature (VCCOff, Oscillator Off)

Lead Solder Temperature for 10 seconds 260 °C
Input or Output Voltages –0.3 to 7 V
Supply Voltage –0.3 to 7 V

Output Current 20 mA
Power Dissipation 1 W

not implied. Expos ure to Absolute Maximum Rat­ing conditions for extended periods may affect de­vice reliability. Refer also to the
STMicroelectronics SURE Program and other rel­evant quality documents.

–40 to 85 °C

6/27

DC AND AC PARAMETERS

This s ec t ion summarizes the operating and mea­surement con ditions, as w ell as t he DC and AC
characteristics of the device. The parameters in
the following DC and AC Characteristic tables are
derived from tests performed under the Measure-

Table 3. Operating and AC Measurement Conditions

Parameter M48T58 M48T58Y Unit

M48T58, M 48T 58Y

ment Conditions listed in the relevant tables. De­signers should check that the operating condit ions
in their projects match the measurement condi­tions when using t he quoted parameters.

Supply Voltage (V
Ambient Operating Temperature (T
Load Capacitance (C

CC

)

)

A

)

L

4.75 to 5.5 4.5 to 5.5 V
0 to 70 0 to 70 °C

100 100 pF
Input Rise and Fall Times ≤ 5 ≤ 5ns
Input Pulse Voltages 0 to 3 0 to 3 V
Input and Output Timing Ref. Voltages 1.5 1.5 V

Note: Output Hi-Z is defined as the point where data is no longer driven.

Figure 7. AC Measurement Load Circuit

5V

1.9kΩ

DEVICE
UNDER

TEST

1kΩ

OUT

CL = 100pF or 5pF

CL includes JIG capacitance

AI01030

Table 4. Capacitance

Symbol

C

IN

(3)

C

OUT

Note: 1. Effective capacitance measured with power supply at 5V; sampled only, not 100% tested.

2. At 25°C, f = 1MHz.

3. Outputs deselected.

Input Capacitance 10 pF
Output Capacitance 10 pF

Parameter

(1,2)

Min Max Unit

7/27

M48T58, M48T58Y

Table 5. DC C haracteristics

Symbol Parameter

Test Condition

(1)

M48T58 M48T58Y

Min Max Min Max

Unit

Input Leakage Current

I

LI

(2)

I

LO

I

I

CC1

I

CC2

V

V

Output Leakage Current
Supply Current Outputs open 50 50 mA

CC

Supply Current (Standby)
TTL

Supply Current (Standby)
CMOS

(3)

Input Low Voltage –0.3 0.8 –0.3 0.8 V

IL

Input High Voltage 2.2

IH

0V ≤ V

0V ≤ V

E1
E2=V

Output Low Voltage

V

OL

Output Low Voltage (FT)

V

Note: 1. ValidforAmbientOperatingTemperature: TA=0to70°C;VCC= 4.75 to 5.5V or 4.5 to 5.5V (except where noted).

Output High Voltage

OH

2. Outputs deselected.

3. Negativespikes of –1V allowed forup to 10ns onceper Cycle.

4. The FT pin is Open Drain.

(4)

≤ V

IN

≤ V

OUT

=V

E1

IH

E2 = V

IO

=VCC– 0.2V

+ 0.2V

SS

I

= 2.1mA

OL

IOL= 10mA

I

=–1mA

OH

CC

CC

±1 ±1 µA
±1 ±1 µA

33mA

33mA

V

CC

+ 0.3

2.2

VCC+0.3

0.4 0.4

0.4 0.4 V

2.4 2.4 V

V

8/27

OPERATION MODES

As Figure 6, page 5 shows, the static memory ar­ray and the quartz controlled clock oscillator of the
M48T58/Y are integrated on one silicon chip. The
two circuits are interconnected at the upper eight
memory locations to p rovide user acce ssible
BYTEWIDE™ clock information in the bytes with
addresses 1FF8h-1FFFh. The clock locations
contain the century, year, month, date, day, hour,
minute, and second in 24 hour BC D format (except
for the c entury). Corrections for 28, 29 (leap year ­valid until 2100), 30, and 31 day m onths are made
automatically. Byte 1FF8h is the clock control reg­ister. This byte controls user access to th e clock
information and also stores the clock calibration
setting.

The eight clock bytes are not the actual clock
counters themselves; t hey are memory locations

Table 6. Operating Modes

Mode

Deselect
Deselect X
WRITE
READ
READ
Deselect

Deselect

Note: X = VIHor VIL;VSO= Battery Back-up Switchover Voltage.

1. See Table 10, page 16 for details.

VSOto V

V

CC

4.75 to 5.5V
or

4.5 to 5.5V

(min)

PFD

(1)

≤ V

SO

E1 E2 G W DQ0-DQ7 Power

(1)

V

IH

V

IL

V

IL

V

IL

X X X X High Z CMOS Standby
X X X X High Z Battery Back-up Mode

X X X High Z Standby

V

IL

V

IH

V

IH

V

IH

M48T58, M 48T 58Y

consisting of BiPO RT™ READ/write memory
cells. The M48T58/Y includes a clock control cir­cuit which updates t he clock bytes with current in­formation once per second. The information can
be accessed by the user in the same manner as
any other location in the static memory array.

The M48T58/Y also has its own Power-fail Detect
circuit. The control c ircuitry constantly monitors
the single 5V supply for an out-of-tolerance condi­tion. When V
protects the SRA M, providing a high degree of
data security in the midst of unpredictable system
operation brought on by low V
low the Bat tery Back-up Switchover Voltage

), the control circuitry connects the battery

(V

SO

which maintains data and clock operation until val­id power returns.

X X High Z Standby
X

V

IL

V

IH

V

IL

V

IH

V

IH

is out of tolerance, the circuit write

CC

.AsVCCfalls be-

CC

D

IN

D

OUT

High Z Active

Active
Active

9/27