HANBIT HMNR328DV-100I

HANBit
HMNR328D(V)
5.0 or 3.3V, 256K bit (32 Kbit x 8) TIMEKEEPER NVSRAM
Part No. HMNR328D(V)
GENERAL DESCRIPTION
The HMNR328D(V) TIMEKEEPER SRAM is a 32Kb x 8 non-volatile static RAM and real time clock organized as 32,768
words by 8 bits. The special DIP package provides a fully integrated battery back-up memory and real time clock solu tion.
The HMNR328D(V) directly replaces industry standard 32Kbit x 8 SRAMs. It also provides the non-volatility of Flash
without any requirement for special WRITE timing or limitations on the number of WRITEs that can be performed.
FEATURES
■ INTEGRATED LOW POWER SRAM, REAL TIME CLOCK, POWER-FAIL CONTROL CIRCUIT, BATTERY and
CRYSTAL
■ BCD CODED YEAR, MONTH, DAY, DATE, HOURS, MINUTES, and SECONDS
■ AUTOMATIC POWER-FAIL CHIP DESELECT and WRITE PROTECTION VOLTAGES :
(VPFD = Power-fail Deselect Voltage)
– HMNR328D : VCC = 4.5 to 5.5V
4.2V ≤ VPFD ≤ 4.5V
– HMNR328DV: VCC = 3.0 to 3.6V
2.7V ≤ VPFD ≤ 3.0V
■ CONVENTIONAL SRAM OPERATION : UNLIMITED WRITE CYCLES
■ SOFTWARE CONTROLLED CLOCK CALIBRATION FOR HIGH ACCURACY APPLICATIONS
■ 10 YEARS OF DATA RETENTION and CLOCK OPERATION IN THE ABSENCE OF POWER PIN and FUNCTION
COMPATIBLE WITH INDUSTRY STANDARD 32K x 8 SRAMS
■ SELF-CONTAINED BATTERY and CRYSTAL IN DIP PACKAGE
OPTIONS
MARKING
PIN ASSIGNMENT
w Timing
70 ns
85 ns
100 ns
A14
A12
-70
-85
A7
A6
A5
A4
A3
-100
A2
A1
A0
DQ0
DQ1
DQ2
VSS
1
28
2
3
4
27
26
25
5
6
7
8
9
10
11
12
13
14
24
23
22
21
20
19
18
17
16
15
VCC
/WE
A13
A8
A9
A11
/OE
A10
/CE
DQ7
DQ6
DQ5
DQ4
DQ3
28-pin Encapsulated Package
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HMNR328D(V)
FUNCTIONAL DESCRIPTION
The HMNR328D(V) is a full function, year 2000 compliant (Y2KC), real – time clock/calendar (RTC) and 32k x 8 non-volatile
static RAM. User access to all registers within the HMNR328D (V) is accomplished with a bytewide interface . The Realtime clock (RTC) information and control bits reside in the sixteen upper most RAM locations. The RTC registers contain
century, year, month, date, day, hours, minutes, and seconds data in 24 -hour BCD format. Corrections for the date of
each month and leap year are made automatically. The RTC clock registers are double buffered to avoid access of
incorrect data that can occur during clock update cycles. The double buffered system also prevents time loss as the
timekeeping countdown continues unabated by access to time register data.
The HMNR328D(V) also contains its own power-fail circuitry which deselects the device when the VCC supply is in an out
of tolerance condition. This feature prevents loss of data from unpredictable system operation brought on by low VCC as
errant access and update cycles are avoided.
BLOCK DIAGRAM
16 x 8
TIMEKEEPER
REGISTER
OSCILLATOR AND
CLOCK CHAIN
32.768KHz
CRYSTAL
A0 ~ A14
POWER
32,752 x 8
SRAM ARRAY
LITHIUM
CELL
VPFD
/CE
VOLTAGE SENSE
AND
SWITCHING
CIRCURITY
/WE
/OE
Vcc
Vss
A0-A14 : Address Input
/WE : Write Enable
/CE : Chip Enable
/OE : Output Enable
Vss : Ground
VCC : Power (+5V or +3.3V)
DQ0-DQ7 : Data In / Data Out
NC : No Connection
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DQ0 ~ DQ7
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HMNR328D(V)
Absolute Maximum Ratings
Symbol
Parameter
Value
Unit
TA
AmbientOperatingTemperature
0 to 70
°C
TSTG
Storage Temperature(Vcc Off, Oscillator Off)
-40 to 70
°C
Lead Solder Temperature for 10 seconds
260
°C
Input or Output Voltage
-0.3 to Vcc+0.3
V
HMNR328D
4.5 to 5.5
V
HMNR328DV
3.0 to 3.6
V
(1)
TSLD
VIO
VCC
Supply Voltage
IO
Output Current
20
mA
PD
Power Dissipation
1
W
Note : Permanent device damage may occur if Absolute Maximum Ratings are exceeded.
Functional operation should be restricted to the Recommended DC Operating Conditions detailed in this data sheet.
Exposure to higher than recommended voltage for extended periods of time could affect device reliability.
(1) Soldering temperature not to exceed 260 ° C for 10 seconds (Total thermal budget not to exceed 15 0° C for longer
than 30 seconds).
Caution : Negative undershoots below – 0.3V are not allowed on any pin while in the Battery Back -up mode.
Operating and AC Measurement Conditions
Parameter
HMNR328D
HMNR328DV
Unit
VCC Supply Voltage
4.5 to 5.5
3.0 to 3.6
V
Ambient Operating Temperature
0 to 70
0 to 70
°C
Load Capacitance (CL )
100
50
pS
Input Rise and Fall Times
≤ 5
≤ 5
nS
Input Pulse Voltages
0 to 3
0 to 3
V
Input and Output Timing Ref. Voltages
1.5
1.5
V
AC Measurement Load Circuit
Note : 50pF for HMNR328DV
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HMNR328D(V)
Capacitance
Symbol
Parameter
Max
Unit
Input Capacitance
10
pF
Input/Output Capacitance
10
pF
CIN
COUT
(3)
(1,2)
Min
Note :
1.
Effective capacitance measured with power supply at 5V ( HMNR328D) or 3.3V (HMNR328DV). Sampled only,
not 100% tested.
2.
At 25° C, f = 1MHz.
3.
Outputs deselected.
DC Characteristics
HMNR328D
HMNR328DV
Parameter
ILI
Input Leakage Current
0V ≤ VIN ≤ VCC
± 1
± 1
uA
Output Leakage Current
0V ≤ VOUT ≤ VCC
± 1
± 1
uA
Supply Current
Outputs open
10
mA
ILO
(2)
ICC
ICC1
ICC2
Supply Current (Standby)
TTL
Supply Current (Standby)
CMOS
Test Condition
(1)
Symbol
Min
8
3
2
mA
800
nA
100
nA
0.8
V
575
VIH
Input High Voltage
2.2
+0.3
V
0.4
0.4
V
VOH Battery Back-up
IOUT2=-1.0uA
2.0
VOUT Current (Active)
VOUT1 > VCC-0.3
VOUT2>VBAT-0.3
VBAT
VCC
2.0
IOL=10mA
VOHB
VSO
+0.3
V
2.4
VPFD
VCC
-0.3
0.4
IOH=-1.0mA
Back-up)
0.8
0.4
Output High Voltage
IOUT2
575
IOL=2.1mA
VOH
VOUT Current (Battery
800
100
-0.3
IOUT1
Unit
/CE=VCC-0.2
Input Low Voltage
(open drain) (4)
4
Max
mA
VIL
Output Low Voltage
15
Typ
3
OFF
VOL
Min
5
Battery Current OSC
Output Low Voltage
Max
/CE=VIH
Battery Current OSC ON
IBAT
Typ
Power-fail Deselect
4.1
Voltage
2.4
3.6
4.35
V
3.6
V
100
70
mA
100
100
uA
3.0
V
4.5
2.0
2.7
2.9
VPFD-
Battery Back-up
3.0
Switchover Voltage
100
V
mV
Battery Voltage
3.0
3.0
V
Note: 1. Valid for Ambient Operating Temperature: TA =0 to 70° C or 40 to 85°C ;
VCC = 4.5 to 5.5V or 3.0 to 3.6V (except where noted).
2. Outputs deselected.
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HMNR328D(V)
OPERATING MODES
The 28-pin, 600mil DIP Hybrid houses a controller chip, SRAM, quartz crystal, and a long life lithium button cell in a single
package. The clock locations conta in the year, month, date, day, hour, minute, and second in 24 hour BCD format.
Corrections for 28, 29 (leap year-compliant until the year 2100), 30, and 31 day months are made automatically. Byte
7FF8h is the clock control register. This byte controls user access to the clock information and also stores the clock
calibration setting. The seven clock bytes (7FFFh -7FF9h) are not the actual clock counters, they are memory locations
consisting of READ/WRITE memory cells within the static RAM array. The HMNR328D includes a clock control circuit
which updates the 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 HMNR328D(V) also has its own Power-Fail
Detect circuit. This control circuitry constantly monitors the supply voltage for an out of tolerance condition.
When VCC is out of tolerance, the circuit write protects the TIMEKEEPER register data and SRAM, providing data security
in the midst of unpredictable system operation. As VCC falls, the control circuitry automatically switches to the battery,
maintaining data and clock operation until valid power is restored.
Operating Modes
Mode
VCC
Deselect
4.5V to 5.5V
WRITE
or
READ
3.0V to 3.6V
READ
/CE
/OE
/WE
DQ7 – DQ0
Power
VIH
X
X
High-Z
Standby
VIL
X
VIL
DIN
Active
VIL
VIL
VIH
DOUT
Active
VIL
VIH
VIH
High
Active
Deselect
VSO to VPFD (min)
X
X
X
High
Deselect
≤ VSO (1)
X
X
X
High
CMOS
Standby
Battery Backup
Note : X = VIH or VIL; VSO = Battery Back-up Switchover Voltage.
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HMNR328D(V)
READ Mode
The HMNR328D(V) is in the READ Mode whenever /WE (WRITE Enable) is high and /CE (Chip Enable) is low. The
unique address specified by the 1 5 Address Inputs defines which one of the 32,768 bytes of data is to be accessed. Valid
data will be available at the Data I/O pins within Address Access Time (tAVQV) after the last address input signal is stable,
providing the /CE and /OE access times are also satisfied. If the /CE and /OE access times are not met, valid data will be
available after the latter of the Chip Enable Access Times ( tELQV) or Output Enable Access Time (tGLQV). The state of the
eight three-state Data I/O signals is controlled by /CE and /OE. If the outputs are activated before tAVQV, the data lines will
be driven to an indeterminate state until tAVQV. If the Address Inputs are changed while /CE and /OE remain active, output
data will remain valid for Output Data Hold Time (tAXQX) but will go indeterminate until the next Address Access.
READ Mode AC Waveforms
/CE
/OE
Note : /WE = High.
READ Mode AC Characteristics
Symbol
HMNR328D
HMNR328D
HMNR328DV
-70
-100
-85
Parameter
Min
Max
Max
100
Min
Max
tAVAV
READ Cycle Time
tAVQV
Address Valid to Output Valid
70
100
85
nS
tELQV
Chip Enable Low to Output Valid
70
100
85
nS
tGLQV
Output Enable Low to Output Valid
35
50
35
nS
(2)
tELQX
70
Min
Unit
85
nS
Chip Enable Low to Output Transition
5
10
5
nS
tGLQX
(2)
Output Enable Low to Output Transition
5
5
0
nS
tEHQZ
(2)
Chip Enable High to Output Hi-Z
25
40
25
nS
(2)
Output Enable High to Output Hi-Z
25
40
25
nS
tGHQZ
tAXQX
Address Transition to Output Transition
10
10
10
nS
Note: 1.Valid for Ambient Operating Temperature: TA = 0 to 70° C; VCC = 4.5 to 5.5V or 3.0 to 3.6V (except where noted).
2. CL = 5pF.
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HMNR328D(V)
WRITE Mode
The HMNR328D(V) is in the WRITE Mode whenever /WE (WRITE Enable) and /CE (Chip Enable) are low state after the
address inputs are stable. The start of a WRITE is referenced from the latter occurring falling edge of /WE or /CE. A
WRITE is terminated by the earlier rising edge of /WE or /CE. The addresses must be held valid throughout the cycle. /CE
or /WE must return high for a minimum of tEHAX from Chip Enable or tWHAX from WRITE Enable prior to the initiation of
another READ or WRITE cycle. Data-in must be valid tDVWH prior to the end of WRITE and remain valid for tWHDX afterward.
/OE should be kept high during WRITE cycles to avoid bus contention; although, if the output bus has been activated by a
low on /CE and /OE a low on /WE will disable the outputs tWLQZ after /WE falls.
WRITE AC Waveforms, WRITE Enable Controlled
A0-A14
WRITE AC Waveforms, Chip Enable Controlled
A0-A14
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HMNR328D(V)
WRITE Mode AC Characteristics
Symbol
Parameter
HMNR328D
HMNR328D
HMNR328DV
-70
-100
-85
(1)
Min
Max
Min
Max
Min
Unit
Max
tAVAV
WRITE Cycle Time
70
100
85
nS
tAVWL
Address Valid to WRITE Enable Low
0
0
0
nS
tAVEL
Address Valid to Chip Enable Low
0
0
0
nS
tWLWH
WRITE Enable Pulse Width
50
80
55
nS
tELEH
Chip Enable Low to Chip Enable High
55
80
60
nS
tWHAX
WRITE Enable High to Address Transition
0
10
0
nS
tEHAX
Chip Enable High to Address Transition
0
10
0
nS
tDVWH
Input Valid to WRITE Enable High
30
50
30
nS
tDVEH
Input Valid to Chip Enable High
30
50
30
nS
tWHDX
WRITE Enable High to Input Transition
5
5
0
nS
tEHDX
Chip Enable High to Input Transition
5
5
0
nS
tWLQZ
(2,3)
WRITE Enable Low to Output High-Z
25
50
25
nS
tAVWH
Address Valid to WRITE Enable High
60
80
65
nS
tAVEH
Address Valid to Chip Enable High
60
80
65
nS
WRITE Enable High to Output Transition
5
5
5
nS
(2,3)
tWHQX
Note : 1. Valid for Ambient Operating Temperature: TA = 0 to 70° C; VCC = 4.5 to 5.5V or 3.0 to 3.6V (except where
noted).
2. CL = 5pF.
3. If /CE goes low simultaneously with /WE going low, the outputs remain in the high impedance state.
Data Retention Mode
With valid VCC applied, the HMNR328D(V) operates as a conventional Bytewide static RAM. Should the supply voltage
decay, the RAM will automatically deselect, write protecting itself when VCC falls between VPFD (max), VPFD (min) window.
All outputs become high impedance and all inputs are treated as “Don't care.”
Note : A power failure during a WRITE cycle may corrupt data at the current addressed location, but does not jeopardize
the rest of the RAM's content. At voltages below VPFD (min), the memory will be in a write protected state, provided the VCC
fall time is not less than tF. The HMNR328D(V) may respond to transient noise spikes on VCC that cross into the deselect
window during the time the device is sampling VCC. Therefore, decoupling of the power supply lines is recommended.
When VCC drops below VSO, the control circuit switches power to the internal battery, preserving data and powering the
clock. The internal energy source will maintain data in the HMNR328D(V) for an accumulated period of at least 10 years
at room temperature. As system power rises above VSO, the battery is disconnected, and the power supply is switched to
external VCC . Write protection continues until VCC reaches VPFD (min) plus tREC (min). Normal RAM operation can resume
tREC after VCC exceeds VPFD (max).
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HMNR328D(V)
Power Down/Up Mode AC Waveforms
Power Down/Up AC Characteristics
Symbol
tF
(2)
tFB
(3)
Parameter
Min
VPFD (max) to VPFD (min) VCC Fall Time
300
uS
HMNR328D
10
uS
HMNR328DV
150
uS
uS
VPFD (min) to VSS VCC Fall Time
tR
VPFD (min) to VPFD (max) VCC Rise Time
10
(4)
tREC
VPFD (max) to RST High
40
tRB
VSS to VPFD (min) VCC Rise Time
5
Max
Unit
200
uS
uS
Note :
1. Valid for Ambient Operating Temperature: TA = 0 to 70° C; VCC = 4.5 to 5.5V or 3.0 to 3.6V (except where noted).
2. VPFD (max) to VPFD (min) fall time of less than tF may result in deselection/write protection not occurring until 200µs after
VCC passes VPFD (min).
3. VPFD (min) to VSS fall time of less than tFB may cause corruption of RAM data.
Power Down/Up Trip Points DC Characteristics
Symbol
VPFD
VSO
Parameter
Power-fail Deselect Voltage
(1,2)
Min
Typ
Max
Unit
HMNR328D
4.2
4.35
4.5
V
HMNR328DV
2.7
2.9
3.0
V
Battery Back-up Switchover
HMNR328D
3.0
V
Voltage
HMNR328DV
VPFD-100mV
V
(3)
TDR
Expected Data Retention Time
10
YEARS
Note: 1. All voltages referenced to VSS .
2. Valid for Ambient Operating Temperature: TA = 0 to 70° C; VCC = 4.5 to 5.5V or 3.0 to 3.6V (except where noted).
3. At 25° C.
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HMNR328D(V)
Register Map
Address
Funtion /
Data
D7
7FFF
D6
D5
D4
D3
D2
10Years
7FFE
0
0
7FFD
0
0
7FFC
0
FT
7FFB
0
0
0
0
0
Range BCD Format
Year
00-99
Month
Month
01-12
Date : Day of Month
Date
01-31
Day
01-07
Hours
00-23
0
10 Hours
D0
Year
10M
10 Date
D1
Day
Hours(24 Hour Format)
7FFA
0
10 Minutes
Minutes
Minutes
00-59
7FF9
ST
10 Seconds
Seconds
Seconds
00-59
7FF8
W
R
S
7FF7
0
0
0
0
0
0
0
0
7FF6
0
0
0
0
0
0
0
0
7FF5
0
0
0
0
0
0
0
0
7FF4
0
0
0
0
0
0
0
0
7FF3
0
0
0
0
0
0
0
0
7FF2
0
0
0
0
0
0
0
0
7FF1
7FF0
Calibration
1000 Years
0
0
0
Control
100 Years
BL
0
0
0
Century
0
00-99
Flag
Keys :
R = READ Bit
W = WRITE Bit
ST = Stop Bit
0 = Must be set to ’0’
BL = Battery Low Flag
S = Sign Bit
CLOCK OPERATIONS
The HMNR328D(V) offers 16 internal registers which contain TIMEKEEPER, and Control data. These registers are
memory locations which contain external (user accessible) and internal copies of the data. The external copies are
independent of internal functions except that they are updated periodically by the simultaneous transfer of the incremented
internal copy. TIMEKEEPER Registers store data in BCD. Control Registers store data in Binary Format.
Reading the Clock
Updates to the TIMEKEEPER registers should be halted before clock data is read to prevent reading data in transition.
The TIMEKEEPER cells in the RAM array are only data registers and not the actual clock counters, so updating the
registers can be halted without disturbing the clock itself. Updating is halted when a ’1’is written to the READ Bit, D6 in the
Control Register (7FF8h). As long as a ’1’remains in that position, updating is halted. After a halt is issued, the registers
reflect the count; that is, the day, date, and time that were current at the moment the halt command was is -sued. All of the
TIMEKEEPER registers are updated simultaneously. A halt will not interrupt an update in progress. Updating occurs
approximately 1 second after the READ Bit is reset to a ’0.’
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HMNR328D(V)
Setting the Clock
Bit D7 of the Control Register (7FF8h) is the WRITE Bit. Setting the WRITE Bit to a ’1,’like the READ Bit, halts updates to
the TIMEKEEPER reg-isters. The user can then load them with the correct day, date, and time data in 24-hour BCD
format. Resetting the WRITE Bit to a ’0’then transfers the
values of all time registers (7FFh -7FF9h, 7FF1h) to the actual TIMEKEEPER counters and allows normal operation to
resume. After the WRITE Bit is reset, the next clock update will occur approximately one second later.
Note: Upon power-up following a power failure, both the WRITE Bit and the READ Bit will be reset to ’0.’
Stopping and Starting the Oscillator
The oscillator may be stopped at any time. If the device is going to spend a significant amount of time on the shelf, the
oscillator can be turned off to minimize current drain on the battery. The STOP Bit is located at Bit D7 within the Seconds
Register (7FF9h). Setting it to a ’1’stops the oscillator. When reset to a ’0,’the HMNR328D oscillator starts within one
second.
Note : It is not necessary to set the WRITE Bit when setting or resetting the STOP Bit (ST).
Calibrating the Clock
The HMNR328D(V) is driven by a quartz controlled oscillator with a nominal frequency of 32,768Hz. The devices are
factory calibrated at 25° C and tested for accuracy. Clock accuracy will not exceed 35 ppm (parts per million) oscillator
frequency error at 25° C, which equates to about ± 1.53 minutes per month. When the Calibration circuit is properly
employed, accuracy improves to better than +1/-2 ppm at 25° C. The oscillation rate of crystals changes with temperature.
The HMNR328D design employs periodic counter correction. The calibration circuit adds or subtracts counts from the
oscillator divider circuit at the divide by 256 stage. The number of times pulses are blanked (subtracted, negative
calibration) or split (added, positive calibration) depends upon the value loaded into the five Calibration bits found in the
Control Register.
Adding counts speeds the clock up, subtracting counts slows the clock down. The Calibration bits occupy the five lower
order bits (D4-D0) in the Control Register 7FF8h. These bits can be set to represent any value between 0 and 31 in binary
form. Bit D5 is a Sign bit; '1' indicates positive calibration, '0' indicates negative calibration. Calibration occurs within a 64
minute cycle. The first 62 minutes in the cycle may, once per minute, have one second either shortened by 128 or
lengthened by 256 oscillator cycles. If a binary '1' is loaded into the register, only the first 2 minutes in the 64 minute cycle
will be modified; if a binary 6 is loaded, the first 12 will be affected, and so on. Therefore, each calibration step has the
effect of adding 512 or subtracting 256 oscillator cycles for every 125, 829, 120 actual oscillator cycles; that is, +4.068 or 2.034 ppm of adjustment per calibration step in the calibration register. Assuming that the oscillator is running at exactly
32,768Hz, each of the 31 increments in the Calibration byte would represent +10.7 or -5.35 seconds per month which
corresponds to a total range of +5.5 or -2.75 minutes per month. One method for ascertaining how much calibration a
given HMNR328D(V) may require involves setting the clock, letting it run for a month and comparing it to a known
accurate reference and recording deviation over a fixed period of time. This allows the designer to give the end user the
ability to calibrate the clock as the environment requires, even if the final product is packaged in a nonuser serviceable
enclosure. The designer could provide a simple utility that accesses the Calibration bits.
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HMNR328D(V)
Battery Low Warning
The HMNR328D(V) automatically performs battery voltage monitoring upon power-up and at factory-programmed time
intervals of approximately 24 hours. The Battery Low (BL) Bit, Bit D4 of Flags Register 7FF0h, will be asserted if the
battery voltage is found to be less than approximately 2.5V. The BL Bit will remain asserted until completion of battery
replacement and subsequent battery low monitoring tests, either during the next power-up sequence or the next
scheduled 24hour interval. If a battery low is generated during a power -up sequence,
this indicates that the battery is below approximately 2.5V and may not be able to maintain
data integrity in the SRAM. Data should be considered suspect and verified as correct. A fresh battery should be installed.
If a battery low indication is generated during the 24-hour interval check, this indicates that the battery is near end of life.
However, data is not compromised
due to the fact that a nominal VCC is supplied. In order to insure data integrity during
Power Supply Decoupling and Undershoot Protection
Note: ICC transients, including those produced by output
switching, can produce voltage fluctuations, resulting in spikes
on the VCC bus. These transients can be reduced if capacitors
are used to store energy which stabilizes the VCC bus. The
energy stored in the bypass capacitors will be released as low
going spikes are generated or energy will be absorbed when
overshoots occur. A ceramic bypass capacitor value of 0.1 uF
is recommended in order to provide the needed filtering. In
addition to transients that are caused by normal
SRAM operation, power cycling can generate negative
voltage spikes on VCC that drive it to values below VSS by as
much as one volt. These negative spikes can cause data
corruption in the SRAM while in battery backup mode. To
protect from these voltage spikes, ST recommends
connecting a schottky diode from VCC to VSS (cathode connected to VCC, anode to VSS). (Schottky diode 1N5817 is
recommended for through hole and MBRS120T3 is recommended for surface mount).
URL : www.hbe.co.kr
Rev. 0.0 (January, 2002)
12
HANBit Electronics Co.,Ltd.
HANBit
HMNR328D(V)
PACKAGE DIMENSION
Dimension
Min
Max
A
1.470
1.500
B
0.710
0.740
C
0.365
0.375
D
0.012
-
E
0.008
0.013
F
0.590
0.630
G
0.017
0.023
H
0.090
0.110
I
0.075
0.110
J
0.120
0.150
J
A
I
H
G
B
C
D
Unit : inch
E
F
ORDERING INFORMATION
H M N R 32 8 D V - 70 I
Operating Temperature : I = Industrial Temp. (-40~85 °C )
Blank = Commercial Temp. (0~70°C)
Speed options : 70 = 70 ns
85 = 85 ns
100 = 100ns
Operating Voltage
: Blank = 5V
V = 3.3V
Dip type package
Device : 32K x 8
Nonvolatile Timekeeping SRAM
HANBit Memory Module
URL : www.hbe.co.kr
Rev. 0.0 (January, 2002)
13
HANBit Electronics Co.,Ltd.