MR4A08B Rev. 8.7 3/20181Copyright © 2018 Everspin Technologies
MR4A08B
2M x 8 MRAM Memory
INTRODUCTION
The MR4A08B is a 16,777,216-bit magnetoresistive random access
memory (MRAM) device organized as 2,097,152 words of 8 bits.
The MR4A08B oers SRAM compatible 35ns read/write timing with
unlimited endurance. Data is always non-volatile for greater than
20-years. Data is automatically protected on power loss by low-
voltage inhibit circuitry to prevent writes with voltage out of specication. The
MR4A08B is the ideal memory solution for applications that must permanently store and retrieve critical
data and programs quickly.
The MR4A08B is available in small footprint 400-mil, 44-lead plastic small-outline TSOP type-II package or
10 mm x 10 mm, 48-pin ball grid array (BGA) package with 0.75 mm ball centers. These packages are com-
patible with similar low-power SRAM products and other non-volatile RAM products.
The MR4A08B provides highly reliable data storage over a wide range of temperatures. The product is of-
fered with commercial (0 to +70 °C) and industrial (-40 to +85 °C) operating temperature range options.
RoHS
CONTENTS
1. DEVICE PIN ASSIGNMENT......................................................................... 2
2. ELECTRICAL SPECIFICATIONS................................................................. 4
3. TIMING SPECIFICATIONS.......................................................................... 7
4. ORDERING INFORMATION....................................................................... 11
5. MECHANICAL DRAWING.......................................................................... 12
6. REVISION HISTORY...................................................................................... 14
How to Reach Us.......................................................................................... 15
FEATURES
+3.3 Volt power supply
Fast 35 ns read/write cycle
SRAM compatible timing
Unlimited read & write endurance
Data always non-volatile for >20-years at temperature
RoHS-compliant small footprint BGA and TSOP2 packages
All products meet MSL-3 moisture sensitivity level
BENEFITS
One memory replaces FLASH, SRAM, EEPROM and BBSRAM in systems
for simpler, more ecient designs
Improves reliability by replacing battery-backed SRAM
MR4A08B Rev. 8 .7 3/20182Copyright © 2018 Everspin Technologies
CHIP
ENABLE
BUFFER
OUTPUT
ENABLE
BUFFER
ADDRESS
BUFFER
WRITE
ENABLE
BUFFER
G
E
21
OUTPUT ENABLE
2M x 8 BIT
MEMORY
ARRAY
ROW
DECODER COLUMN
DECODER
SENSE
AMPS
OUTPUT
BUFFER
WRITE
DRIVER
FINAL
WRITE
DRIVERS
WRITE ENABLE
W
A[20:0]
11
10
88
8
8
8
8
DQ[7:0]
1. DEVICE PIN ASSIGNMENT
Figure 1.1 Block Diagram
Table 1.1 Pin Functions
Signal Name Function
A Address Input
E Chip Enable
W Write Enable
G Output Enable
DQ Data I/O
VDD Power Supply
VSS Ground
DC Do Not Connect
NC No Connection
MR4A08B
MR4A08B Rev. 8.7 3/20183Copyright © 2018 Everspin Technologies
A
A
A
A
VDD
E
VSS
W
A
A
A
DC
A
DC 22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44 DC
A
A
DC
A
G
VSS
A
VDD
DC
A
A
A
A
A
DC
DC
A
A
A
A20 19
DC
123456
G A A A A
AAEB
DQ AA
DQ
DQ C
VSS
DQ
VDD D
VDD
DQ
VSS E
DQ
A A
DQ F
NC
AA
WG
NC
A
AH
NCNC
NC
NC
DCDC
DCDC
A
20
19
DQ3
NC
DC
Figure 1.2 Pin Diagrams for Available Packages (Top View)
44 Pin TSOP2 48 Pin FBGA
Table 1.2 Operating Modes
E1G1W1Mode VDD Current DQ[7:0]2
H X X Not selected ISB1, ISB2 Hi-Z
L H H Output disabled IDDR Hi-Z
L L H Byte Read IDDR DOut
L X L Byte Write IDDW Din
1 H = high, L = low, X = don’t care
2 Hi-Z = high impedance
DEVICE PIN ASSIGNMENT MR4A08B
MR4A08B Rev. 8 .7 3/20184Copyright © 2018 Everspin Technologies
2. ELECTRICAL SPECIFICATIONS
Absolute Maximum Ratings
This device contains circuitry to protect the inputs against damage caused by high static voltages or
electric elds; however, it is advised that normal precautions be taken to avoid application of any
voltage greater than maximum rated voltages to these high-impedance (Hi-Z) circuits.
The device also contains protection against external magnetic elds. Precautions should be taken
to avoid application of any magnetic eld more intense than the maximum eld intensity specied
in the maximum ratings.
Parameter Symbol Value Unit
Supply voltage2VDD -0.5 to 4.0 V
Voltage on any pin2VIN
-0.5 to VDD +
0.5 V
Output current per pin IOUT ±20 mA
Package power dissipation 3PD0.600 W
Temperature under bias
MR4A08B (Commercial)
MR4A08BC (Industrial) TBIAS
-10 to 85
-45 to 95 °C
Storage Temperature Tstg -55 to 150 °C
Lead temperature during solder (3 minute max) TLead 260 °C
Maximum magnetic eld during write
MR4A08B (All Temperatures) Hmax_write 8000 A/m
Maximum magnetic eld during read or standby Hmax_read 8000 A/m
1 Permanent device damage may occur if absolute maximum ratings are exceeded. Functional opera-
tion should be restricted to recommended operating conditions. Exposure to excessive voltages or
magnetic elds could aect device reliability.
2 All voltages are referenced to VSS.
3 Power dissipation capability depends on package characteristics and use environment.
Table 2.1 Absolute Maximum Ratings1
MR4A08B
MR4A08B Rev. 8.7 3/20185Copyright © 2018 Everspin Technologies
Parameter Symbol Min Typical Max Unit
Power supply voltage VDD 3.0 13.3 3.6 V
Write inhibit voltage VWI 2.5 2.7 3.0 1 V
Input high voltage VIH 2.2 - VDD + 0.3 2 V
Input low voltage VIL -0.5 3- 0.8 V
Temperature under bias
MR4A08B (Commercial)
MR4A08BC (Industrial) TA
0
-40
70
85 °C
1. There is a 2 ms startup time once VDD exceeds VDD,(min). See Power Up and Power Down Sequencing below.
2. VIH(max) = VDD + 0.3 VDC ; VIH(max) = VDD + 2.0 VAC (pulse width ≤ 10 ns) for I ≤ 20.0 mA.
3. VIL(min) = -0.5 VDC ; VIL(min) = -2.0 VAC (pulse width ≤ 10 ns) for I ≤ 20.0 mA.
Table 2.2 Operating Conditions
Power Up and Power Down Sequencing
MRAM is protected from write operations whenever VDD is less than VWI. As soon as VDD exceeds VDD(min),
there is a startup time of 2 ms before read or write operations can start. This time allows memory power
supplies to stabilize.
The E and W control signals should track VDD on power up to VDD- 0.2 V or VIH (whichever is lower) and re-
main high for the startup time. In most systems, this means that these signals should be pulled up with a
resistor so that signal remains high if the driving signal is Hi-Z during power up. Any logic that drives E and
W should hold the signals high with a power-on reset signal for longer than the startup time.
During power loss or brownout where VDD goes below VWI, writes are protected and a startup time must be
observed when power returns above VDD(min).
BROWNOUT or POWER LOSS
NORMAL
OPERATION
VDD
READ/WRITE
INHIBITED
VWIDD
2 ms
READ/WRITE
INHIBITED
VIH
STARTUP
NORMAL
OPERATION
2 ms
E
W
RECOVER
VIH
Figure 2.1 Power Up and Power Down Diagram
MR4A08B
Electrical Specications
MR4A08B Rev. 8 .7 3/20186Copyright © 2018 Everspin Technologies
Parameter Symbol Min Typical Max Unit
Input leakage current Ilkg(I) - - ±1 μA
Output leakage current Ilkg(O) - - ±1 μA
Output low voltage
(IOL = +4 mA)
(IOL = +100 μA)
VOL - - 0.4
VSS + 0.2
V
Output high voltage
(IOL = -4 mA)
(IOL = -100 μA)
VOH 2.4
VDD - 0.2
- - V
Table 2.3 DC Characteristics
Table 2.4 Power Supply Characteristics
Parameter Symbol Typical Max Unit
AC active supply current - read modes1
(IOUT= 0 mA, VDD= max) IDDR 60 68 mA
AC active supply current - write modes1
(VDD= max) IDDW 152 180 mA
AC standby current
(VDD= max, E = VIH)
no other restrictions on other inputs
ISB1 9 14 mA
CMOS standby current
(E ≥ VDD - 0.2 V and VIn VSS + 0.2 V or ≥ VDD - 0.2 V)
(VDD = max, f = 0 MHz)
ISB2 5 9 mA
1 All active current measurements are measured with one address transition per cycle and at minimum cycle time.
MR4A08B
Electrical Specications
MR4A08B Rev. 8.7 3/20187Copyright © 2018 Everspin Technologies
Parameter Value Unit
Logic input timing measurement reference level 1.5 V
Logic output timing measurement reference level 1.5 V
Logic input pulse levels 0 or 3.0 V
Input rise/fall time 2 ns
Output load for low and high impedance parameters See Figure 3.1
Output load for all other timing parameters See Figure 3.2
Parameter Symbol Typical Max Unit
Address input capacitance CIn - 6 pF
Control input capacitance CIn - 6 pF
Input/Output capacitance CI/O - 8 pF
1 f = 1.0 MHz, dV = 3.0 V, TA = 25 °C, periodically sampled rather than 100% tested.
MR4A08B
3. TIMING SPECIFICATIONS
Table 3.1 Capacitance1
Table 3.2 AC Measurement Conditions
Figure 3.1 Output Load Test Low and High
Figure 3.2 Output Load Test All Others
V
Output
L= 1.5 V
RL= 50 Ω
ZD= 50 Ω
Output
435 Ω
590 Ω
5 pF
3.3 V
MR4A08B Rev. 8 .7 3/20188Copyright © 2018 Everspin Technologies
MR4A08B
Timing Specications
Parameter Symbol Min Max Unit
Read cycle time tAVAV 35 - ns
Address access time tAVQV - 35 ns
Enable access time2tELQV - 35 ns
Output enable access time tGLQV - 15 ns
Output hold from address change tAXQX 3 - ns
Enable low to output active3tELQX 3 - ns
Output enable low to output active3tGLQX 0 - ns
Enable high to output Hi-Z3tEHQZ 0 15 ns
Output enable high to output Hi-Z3tGHQZ 0 10 ns
1 W is high for read cycle. Power supplies must be properly grounded and decoupled, and bus contention conditions must be
minimized or eliminated during read or write cycles.
2 Addresses valid before or at the same time E goes low.
3 This parameter is sampled and not 100% tested. Transition is measured ±200 mV from the steady-state voltage.
Table 3.3 Read Cycle Timing1
Read Mode
Figure 3.3A Read Cycle 1
Figure 3.3B Read Cycle 2
A (ADDRESS)
Q (DATA OUT)
tAVAV
tAXQX
tAVQV
Previous Data Valid
Note: Device is continuously selected (E≤VIL, G≤VIL).
Data Valid
A (ADDRESS)
E (CHIP ENABLE)
G (OUTPUT ENABLE)
Q (DATA OUT) Data Valid
tAVAV
tAVQV
tELQV
tELQX
tGHQZ
tEHQZ
tGLQV
tGLQX
MR4A08B Rev. 8.7 3/20189Copyright © 2018 Everspin Technologies
MR4A08B
Timing Specications
Table 3.4 Write Cycle Timing 1 (W Controlled)1
Parameter Symbol Min Max Unit
Write cycle time2tAVAV 35 - ns
Address set-up time tAVWL 0 - ns
Address valid to end of write (G high) tAVWH 18 - ns
Address valid to end of write (G low) tAVWH 20 - ns
Write pulse width (G high) tWLWH
tWLEH
15 - ns
Write pulse width (G low) tWLWH
tWLEH
15 - ns
Data valid to end of write tDVWH 10 - ns
Data hold time tWHDX 0 - ns
Write low to data Hi-Z3tWLQZ 0 12 ns
Write high to output active3tWHQX 3 - ns
Write recovery time tWHAX 12 - ns
1 All write occurs during the overlap of E low and W low. Power supplies must be properly grounded and decoupled and bus
contention conditions must be minimized or eliminated during read and write cycles. If G goes low at the same time or after
W goes low, the output will remain in a high impedance state. After W, E or UB/LB has been brought high, the signal must
remain in steady-state high for a minimum of 2 ns. The minimum time between E being asserted low in one cycle to E being
asserted low in a subsequent cycle is the same as the minimum cycle time allowed for the device.
2 All write cycle timings are referenced from the last valid address to the rst transition address.
3 This parameter is sampled and not 100% tested. Transition is measured ±200 mV from the steady-state voltage. At any given
voltage or temperature, tWLQZ(max) < tWHQX(min)
W (WRITE ENABLE)
A (ADDRESS)
E (CHIP ENABLE)
t
AVAV
t
AVWH
t
WHAX
t
AVWL
t
WLEH
t
WLWH
DATA VALID
t
DVWH
t
WHDX
Q (DATA OUT)
D (DATA IN)
t
WLQZ
t
WHQX
Hi -Z Hi -Z
Figure 3.4 Write Cycle Timing 1 (W Controlled)
MR4A08B Rev. 8 .7 3/201810Copyright © 2018 Everspin Technologies
MR4A08B
Timing Specications
Table 3.5 Write Cycle Timing 2 (E Controlled)1
Figure 3.5 Write Cycle Timing 2 (E Controlled)
Parameter Symbol Min Max Unit
Write cycle time 2tAVAV 35 - ns
Address set-up time tAVEL 0 - ns
Address valid to end of write (G high) tAVEH 18 - ns
Address valid to end of write (G low) tAVEH 20 - ns
Enable to end of write (G high) tELEH
tELWH
15 - ns
Enable to end of write (G low) 3tELEH
tELWH
15 - ns
Data valid to end of write tDVEH 10 - ns
Data hold time tEHDX 0 - ns
Write recovery time tEHAX 12 - ns
1 All write occurs during the overlap of E low and W low. Power supplies must be properly grounded and decoupled and bus
contention conditions must be minimized or eliminated during read and write cycles. If G goes low at the same time or after
W goes low, the output will remain in a high impedance state. After W, E or UB/ LB has been brought high, the signal must
remain in steady-state high for a minimum of 2 ns. The minimum time between E being asserted low in one cycle to E being
asserted low in a subsequent cycle is the same as the minimum cycle time allowed for the device.
2 All write cycle timings are referenced from the last valid address to the rst transition address.
3 If E goes low at the same time or after W goes low, the output will remain in a high-impedance state. If E goes high at the
same time or before W goes high, the output will remain in a high-impedance state.
A (ADDRESS)
E (CHIP ENABLE)
W (WRITE ENABLE)
Q (DATA OUT)
D (DATA IN)
t
AVAV
t
AVEH
t
EHAX
t
ELEH
t
EHDX
t
DVEH
t
AVEL
Hi-Z
t
ELWH
Data Valid
MR4A08B Rev. 8.7 3/201811Copyright © 2018 Everspin Technologies
MR4A08B
4. ORDERING INFORMATION
Figure 4.1 Part Numbering System
Carrier (Blank = Tray, R = Tape & Reel)
Speed (35 ns)
Package (YS = TSOP2, MA = FBGA)
Temperature Range
(Blank= Commercial (0 to +70°C),
C= Industrial (-40 to +85°C)
Revision
Data Width (08 = 8-Bit)
Type (A = Asynchronous)
Density (4 =16Mb)
Magnetoresistive RAM (MR)
MR 4 A 08 B C YS 35 R
Grade Temp Range Package Shipping Container Part Number
Commercial 0 to +70°C
44-TSOP2 Tray MR4A08BYS35
Tape and Reel MR4A08BYS35R
48-BGA Tray MR4A08BMA35
Tape and Reel MR4A08BMA35R
Industrial -40 to +85°C
44-TSOP2 Tray MR4A08BCYS35
Tape and Reel MR4A08BCYS35R
48-BGA Tray MR4A08BCMA35
Tape and Reel MR4A08BCMA35R
Table 4.1 Available Parts
MR4A08B Rev. 8 .7 3/201812Copyright © 2018 Everspin Technologies
Figure 5.1 TSOP2
MR4A08B
5. MECHANICAL DRAWING
Print Version Not To Scale
1. Dimensions and tolerances per ASME Y14.5M - 1994.
2. Dimensions in Millimeters.
3. Dimensions do not include mold protrusion.
4. Dimension does not include DAM bar protrusions.
DAM Bar protrusion shall not cause the lead width to exceed 0.58.
MR4A08B Rev. 8.7 3/201813Copyright © 2018 Everspin Technologies
123456
(DATUM A)
(DATUM B)
SEATING PLANE
PIN A1
INDEX
PIN A1
INDEX
A
B
C
D
E
F
G
H
BOTTOM VIEW TOP VIEW
SOLDER BALL DIAMETER REFERS
TO POST REFLOW CONDITION.
THE PRE-REFLOW DIAMETER IS
ø
0.35mm
Figure 5.2 FBGA
MR4A08B
Mechanical Drawings
Ref Min Nominal Max
A 1.19 1.27 1.35
A1 0.22 0.27 0.32
b0.31 0.36 0.41
D10.00 BSC
E10.00 BSC
D1 5.25 BSC
E1 3.75 BSC
DE 0.375 BSC
SE 0.375 BSC
e0.75 BSC
Not To Scale
1. Dimensions in Millimeters.
2. The e’ represents the basic solder ball grid pitch.
3. ‘b is measurable at the maximum solder ball diameter
in a plane parallel to datum C.
4. Dimension ddd’ is measured parallel to primary datum
C.
5. Primary datum C (seating plane) is dened by the
crowns of the solder balls.
6. Package dimensions refer to JEDEC MO-205 Rev. G.
Ref Tolerance of, from and position
aaa 0.10
bbb 0.10
ddd 0.10
eee 0.15
f 0.08
MR4A08B Rev. 8 .7 3/201814Copyright © 2018 Everspin Technologies
MR4A08B
Revision Date Description of Change
1 May 29, 2009 Establish Speed and Power Specications
2 July 27, 2009 Increase BGA Package to 11 mm x 11 mm
3 May 5, 2010 Changed speed marking and timing specs to 35 ns part. Changed BGA package to
10 mm x 10mm
4 Aug 10, 2011 Max. magnetic eld during write (Hmax_write ) increased to 8000 A/m.
5 March 1, 2012 Added preliminary information on AEC-Q100 Grade 1.
6September 20,
2013 Replaced missing VOH specication line in Table 2.3.
7 April 25, 2014 AEC-Q100 removed until qualied product is available.
8September 17,
2014 48-BGA package options moisture sensitivity level upgraded to MSL-5.
8.1 May 19, 2015 Revised Everspin contact information.
8.2 June 11, 2015 Corrected Japan Sales Oce telephone number.
8.3 July 29, 2015 Minor correction to the ddd’ tolerance value for the BGA Package (Note 4.)
8.4 March 11, 2016 The BGA package moisture sensitivity level rating is changed to MSL-6 in Table 4.1.
8.5 November 22,
2016 The BGA package moisture sensitivity level rating is changed to MSL-5 in Table 4.1.
8.6 May 9, 2017 The BGA package moisture sensitivity level is upgraded to MSL-3
8.7 March 23, 2018 Updated the Contact Us table
6. REVISION HISTORY
MR4A08B Rev. 8.7 3/201815Copyright © 2018 Everspin Technologies
Everspin Technologies, Inc.
Information in this document is provided solely to enable system
and software implementers to use Everspin Technologies products.
There are no express or implied licenses granted hereunder to design
or fabricate any integrated circuit or circuits based on the informa-
tion in this document. Everspin Technologies reserves the right to
make changes without further notice to any products herein. Ever-
spin makes no warranty, representation or guarantee regarding the
suitability of its products for any particular purpose, nor does Ever-
spin Technologies assume any liability arising out of the application
or use of any product or circuit, and specically disclaims any and
all liability, including without limitation consequential or incidental
damages. Typical” parameters, which may be provided in Everspin
Technologies data sheets and/or specications can and do vary in
dierent applications and actual performance may vary over time.
All operating parameters including Typicals” must be validated for
each customer application by customers technical experts. Everspin
Technologies does not convey any license under its patent rights
nor the rights of others. Everspin Technologies products are not
designed, intended, or authorized for use as components in systems
intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in
which the failure of the Everspin Technologies product could cre-
ate a situation where personal injury or death may occur. Should
Buyer purchase or use Everspin Technologies products for any such
unintended or unauthorized application, Buyer shall indemnify and
hold Everspin Technologies and its ocers, employees, subsidiaries,
aliates, and distributors harmless against all claims, costs, damages,
and expenses, and reasonable attorney fees arising out of, directly
or indirectly, any claim of personal injury or death associated with
such unintended or unauthorized use, even if such claim alleges that
Everspin Technologies was negligent regarding the design or manu-
facture of the part. Everspin™ and the Everspin logo are trademarks
of Everspin Technologies, Inc. All other product or service names are
the property of their respective owners.
Copyright © 2018 Everspin Technologies, Inc.
7. HOW TO CONTACT US
MR4A08B
How to Reach Us:
Home Page:
www.everspin.com
World Wide Information Request
WW Headquarters - Chandler, AZ
5670 W. Chandler Blvd., Suite 100
Chandler, Arizona 85226
Tel: +1-877-480-MRAM (6726)
Local Tel: +1-480-347-1111
Fax: +1-480-347-1175
support@everspin.com
orders@everspin.com
sales@everspin.com
Europe, Middle East and Africa
Everspin Europe Support
support.europe@everspin.com
Japan
Everspin Japan Support
support.japan@everspin.com
Asia Pacic
Everspin Asia Support
support.asia@everspin.com
Filename:
EST00356_MR4A08B_Datasheet_Rev8.7 032318