GSI GS88037BT-250

GS88037BT-333/300/250/200
256K x 36
9Mb Sync Burst SRAM
100-Pin TQFP
Commercial Temp
Industrial Temp
Features
• Single Cycle Deselect (SCD) operation
• 2.5 V or 3.3 V +10%/–10% core power supply
• 2.5 V or 3.3 V I/O supply
• LBO pin for Linear or Interleaved Burst mode
• Internal input resistors on mode pins allow floating mode pins
• Default to Interleaved Pipeline mode
• Byte Write (BW) and/or Global Write (GW) operation
• Internal self-timed write cycle
• Automatic power-down for portable applications
• JEDEC-standard 100-lead TQFP package
• Pb-Free 100-lead TQFP package available
Functional Description
333 MHz–200 MHz
2.5 V or 3.3 V VDD
2.5 V or 3.3 V I/O
Burst mode, subsequent burst addresses are generated
internally and are controlled by ADV. The burst address
counter may be configured to count in either linear or
interleave order with the Linear Burst Order (LBO) input. The
Burst function need not be used. New addresses can be loaded
on every cycle with no degradation of chip performance.
SCD Pipelined Reads
The GS88037BT is a SCD (Single Cycle Deselect) pipelined
synchronous SRAM. DCD (Dual Cycle Deselect) versions are
also available. SCD SRAMs pipeline deselect commands one
stage less than read commands. SCD RAMs begin turning off
their outputs immediately after the deselect command has been
captured in the input registers.
Byte Write and Global Write
Byte write operation is performed by using Byte Write enable
(BW) input combined with one or more individual byte write
signals (Bx). In addition, Global Write (GW) is available for
writing all bytes at one time, regardless of the Byte Write
control inputs.
Applications
The GS88037BT is a 9,437,184-bit (8,388,608-bit for x32
version) high performance synchronous SRAM with a
2-bit burst address counter. Although of a type originally
developed for Level 2 Cache applications supporting high
performance CPUs, the device now finds application in
synchronous SRAM applications, ranging from DSP main
store to networking chip set support.
Sleep Mode
Low power (Sleep mode) is attained through the assertion
(High) of the ZZ signal, or by stopping the clock (CK).
Memory data is retained during Sleep mode.
Controls
Addresses, data I/Os, chip enables (E1, E2, E3), address burst
control inputs (ADSP, ADSC, ADV), and write control inputs
(Bx, BW, GW) are synchronous and are controlled by a
positive-edge-triggered clock input (CK). Output enable (G)
and power down control (ZZ) are asynchronous inputs. Burst
cycles can be initiated with either ADSP or ADSC inputs. In
Core and Interface Voltages
The GS88037BT operates on a 2.5 V or 3.3 V power supply.
All input are 3.3 V and 2.5 V compatible. Separate output
power (VDDQ) pins are used to decouple output noise from the
internal circuits and are 3.3 V and 2.5 V compatible.
Parameter Synopsis
Pipeline
3-1-1-1
3.3 V
2.5 V
Rev: 1.04 2/2005
tKQ
tCycle
Curr (x36)
Curr (x36)
-333
2.0
3.0
-300
2.2
3.3
-250
2.3
4.0
-200
2.7
5.0
Unit
ns
ns
435
435
395
395
330
330
270
270
mA
mA
1/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
A
A
E1
E2
BD
BC
BB
BA
E3
VDD
VSS
CK
GW
BW
G
ADSC
ADSP
ADV
A
A
GS88037B 100-Pin TQFP Pinout
DQPC
DQC
DQC
VDDQ
VSS
DQC
DQC
DQC
DQC
VSS
VDDQ
DQC
DQC
DQPB
DQB
DQB
VDDQ
VSS
DQB
DQB
DQB
DQB
VSS
VDDQ
DQB
DQB
VSS
NC
VDD
ZZ
DQA
DQA
VDDQ
VSS
DQA
DQA
DQA
DQA
VSS
VDDQ
DQA
DQA
DQPA
LBO
A
A
A
A
A1
A0
NC
NC
VSS
VDD
NC
A
A
A
A
A
A
A
A
VDDQ/DNU
VDD
NC
VSS
DQD
DQD
VDDQ
VSS
DQD
DQD
DQD
DQD
VSS
VDDQ
DQD
DQD
DQPD
100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81
1
80
2
79
3
78
4
77
5
76
6
75
7
74
8
73
9
72
256K x 36
10
71
Top View
11
70
12
69
13
68
14
67
15
66
16
65
17
64
18
63
19
62
20
61
21
60
22
59
23
58
24
57
25
56
26
55
27
54
28
53
29
52
30
51
31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
Rev: 1.04 2/2005
2/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
TQFP Pin Description
Symbol
Type
Description
A 0, A 1
I
Address field LSBs and Address Counter preset Inputs
A
I
Address Inputs
DQA
DQB
DQC
DQD
I/O
Data Input and Output pins
NC
—
No Connect
BW
I
Byte Write—Writes all enabled bytes; active low
BA , BB
I
Byte Write Enable for DQA, DQB Data I/Os; active low
BC , BD
I
Byte Write Enable for DQC, DQD Data I/Os; active low
CK
I
Clock Input Signal; active high
GW
I
Global Write Enable—Writes all bytes; active low
E 1, E 3
I
Chip Enable; active low
E2
I
Chip Enable; active high
G
I
Output Enable; active low
ADV
I
Burst address counter advance enable; active low
ADSP, ADSC
I
Address Strobe (Processor, Cache Controller); active low
ZZ
I
Sleep Mode control; active high
LBO
I
Linear Burst Order mode; active low
VDD
I
Core power supply
VSS
I
I/O and Core Ground
VDDQ
I
Output driver power supply
VDDQ/DNU
—
VDDQ or VDD (must be tied high)
or
Do Not Use (must be left floating)
Rev: 1.04 2/2005
3/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
GS88037B Block Diagram
A0–An
Register
D
Q
A0
A0
D0
A1
Q0
A1
D1
Q1
Counter
Load
A
LBO
ADV
Memory
Array
CK
ADSC
ADSP
Q
D
Register
GW
BW
BA
D
Q
Register
D
36
Q
BB
36
4
Register
D
Q
D
Q
D
Q
Register
Register
D
Q
Register
BC
BD
Register
D
Q
Register
E1
E2
E3
D
Q
Register
D
Q
1
G
ZZ
1
Power Down
Control
DQx1–DQx9
Note: Only x36 version shown for simplicity.
Rev: 1.04 2/2005
4/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Mode Pin Functions
Mode Name
Pin
Name
Burst Order Control
LBO
Power Down Control
ZZ
State
Function
L
Linear Burst
H
Interleaved Burst
L or NC
Active
H
Standby, IDD = ISB
Note:
There is a pull-down device on the ZZ pin, so this input pin can be unconnected and the chip will operate in the default states as specified in the
above tables.
Burst Counter Sequences
Linear Burst Sequence
Interleaved Burst Sequence
A[1:0] A[1:0] A[1:0] A[1:0]
A[1:0] A[1:0] A[1:0] A[1:0]
1st address
00
01
10
11
1st address
00
01
10
11
2nd address
01
10
11
00
2nd address
01
00
11
10
3rd address
10
11
00
01
3rd address
10
11
00
01
4th address
11
00
01
10
Note:
The burst counter wraps to initial state on the 5th clock.
4th address
11
10
01
00
Note:
The burst counter wraps to initial state on the 5th clock.
BPR 1999.05.18
Rev: 1.04 2/2005
5/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Byte Write Truth Table
Function
GW
BW
BA
BB
BC
BD
Notes
Read
H
H
X
X
X
X
1
Read
H
L
H
H
H
H
1
Write byte a
H
L
L
H
H
H
2, 3
Write byte b
H
L
H
L
H
H
2, 3
Write byte c
H
L
H
H
L
H
2, 3, 4
Write byte d
H
L
H
H
H
L
2, 3, 4
Write all bytes
H
L
L
L
L
L
2, 3, 4
Write all bytes
L
X
X
X
X
X
Notes:
1. All byte outputs are active in read cycles regardless of the state of Byte Write Enable inputs.
2. Byte Write Enable inputs BA, BB, BC and/or BD may be used in any combination with BW to write single or multiple bytes.
3. All byte I/Os remain High-Z during all write operations regardless of the state of Byte Write Enable inputs.
4. Bytes “C” and “D” are only available on the x32 and x36 versions.
Rev: 1.04 2/2005
6/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Synchronous Truth Table
Operation
Address
Used
State
Diagram
Key5
E1
E2
Deselect Cycle, Power Down
None
X
H
X
X
Deselect Cycle, Power Down
None
X
L
F
Deselect Cycle, Power Down
None
X
L
Read Cycle, Begin Burst
External
R
Read Cycle, Begin Burst
External
Write Cycle, Begin Burst
ADV
W3
DQ4
L
X
X
High-Z
L
X
X
X
High-Z
F
H
L
X
X
High-Z
L
T
L
X
X
X
Q
R
L
T
H
L
X
F
Q
External
W
L
T
H
L
X
T
D
Read Cycle, Continue Burst
Next
CR
X
X
H
H
L
F
Q
Read Cycle, Continue Burst
Next
CR
H
X
X
H
L
F
Q
Write Cycle, Continue Burst
Next
CW
X
X
H
H
L
T
D
Write Cycle, Continue Burst
Next
CW
H
X
X
H
L
T
D
Read Cycle, Suspend Burst
Current
X
X
H
H
H
F
Q
Read Cycle, Suspend Burst
Current
H
X
X
H
H
F
Q
Write Cycle, Suspend Burst
Current
X
X
H
H
H
T
D
Write Cycle, Suspend Burst
Current
H
X
X
H
H
T
D
ADSP ADSC
Notes:
1. X = Don’t Care, H = High, L = Low
2. E = T (True) if E2 = 1 and E3 = 0; E = F (False) if E2 = 0 or E3 = 1
3. W = T (True) and F (False) is defined in the Byte Write Truth Table preceding.
4. G is an asynchronous input. G can be driven high at any time to disable active output drivers. G low can only enable active drivers (shown
as “Q” in the Truth Table above).
5. All input combinations shown above are tested and supported. Input combinations shown in gray boxes need not be used to accomplish
basic synchronous or synchronous burst operations and may be avoided for simplicity.
6. Tying ADSP high and ADSC low allows simple non-burst synchronous operations. See BOLD items above.
7. Tying ADSP high and ADV low while using ADSC to load new addresses allows simple burst operations. See ITALIC items above.
Rev: 1.04 2/2005
7/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Simplified State Diagram
X
Deselect
W
R
Simple Burst Synchronous Operation
Simple Synchronous Operation
W
X
R
R
First Write
CW
First Read
CR
CR
W
X
R
R
X
Burst Write
Burst Read
X
CR
CW
CR
Notes:
1. The diagram shows only supported (tested) synchronous state transitions. The diagram presumes G is tied low.
2. The upper portion of the diagram assumes active use of only the Enable (E1, E2, and E3) and Write (BA, BB, BC, BD, BW, and GW)
control inputs, and that ADSP is tied high and ADSC is tied low.
3. The upper and lower portions of the diagram together assume active use of only the Enable, Write, and ADSC control inputs, and
assumes ADSP is tied high and ADV is tied low.
Rev: 1.04 2/2005
8/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Simplified State Diagram with G
X
Deselect
W
R
W
X
R
R
First Write
CR
CW
W
CW
W
X
First Read
X
CR
R
Burst Write
R
CR
CW
W
Burst Read
X
CW
CR
Notes:
1. The diagram shows supported (tested) synchronous state transitions plus supported transitions that depend upon the use of G.
2. Use of “Dummy Reads” (Read Cycles with G High) may be used to make the transition from Read cycles to Write cycles without passing
through a Deselect cycle. Dummy Read cycles increment the address counter just like normal read cycles.
3. Transitions shown in gray tone assume G has been pulsed high long enough to turn the RAM’s drivers off and for incoming data to meet
Data Input Set Up Time.
Rev: 1.04 2/2005
9/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Absolute Maximum Ratings
(All voltages reference to VSS)
Symbol
Description
Value
Unit
VDD
Voltage on VDD Pins
–0.5 to 4.6
V
VDDQ
Voltage in VDDQ Pins
–0.5 to 4.6
V
VCK
Voltage on Clock Input Pin
–0.5 to 6
V
VI/O
Voltage on I/O Pins
–0.5 to VDDQ +0.5 (≤ 4.6 V max.)
V
VIN
Voltage on Other Input Pins
–0.5 to VDD +0.5 (≤ 4.6 V max.)
V
IIN
Input Current on Any Pin
+/–20
mA
IOUT
Output Current on Any I/O Pin
+/–20
mA
PD
Package Power Dissipation
1.5
W
TSTG
Storage Temperature
–55 to 125
o
TBIAS
Temperature Under Bias
–55 to 125
o
C
C
Note:
Permanent damage to the device may occur if the Absolute Maximum Ratings are exceeded. Operation should be restricted to Recommended
Operating Conditions. Exposure to conditions exceeding the Absolute Maximum Ratings, for an extended period of time, may affect reliability of
this component.
Power Supply Voltage Ranges
Parameter
Symbol
Min.
Typ.
Max.
Unit
3.3 V Supply Voltage
VDD3
3.0
3.3
3.6
V
2.5 V Supply Voltage
VDD2
2.3
2.5
2.7
V
3.3 V VDDQ I/O Supply Voltage
VDDQ3
3.0
3.3
3.6
V
2.5 V VDDQ I/O Supply Voltage
VDDQ2
2.3
2.5
2.7
V
Notes
Notes:
1. The part numbers of Industrial Temperature Range versions end the character “I”. Unless otherwise noted, all performance specifications quoted are evaluated for worst case in the temperature range marked on the device.
2. Input Under/overshoot voltage must be –2 V > Vi < VDDn+2 V not to exceed 4.6 V maximum, with a pulse width not to exceed 20% tKC.
Rev: 1.04 2/2005
10/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
VDDQ3 Range Logic Levels
Parameter
Symbol
Min.
Typ.
Max.
Unit
Notes
VDD Input High Voltage
VIH
2.0
—
VDD + 0.3
V
1
VDD Input Low Voltage
VIL
–0.3
—
0.8
V
1
VDDQ I/O Input High Voltage
VIHQ
2.0
—
VDDQ + 0.3
V
1,3
VDDQ I/O Input Low Voltage
VILQ
–0.3
—
0.8
V
1,3
Notes:
1. The part numbers of Industrial Temperature Range versions end the character “I”. Unless otherwise noted, all performance specifications quoted are evaluated for worst case in the temperature range marked on the device.
2. Input Under/overshoot voltage must be –2 V > Vi < VDDn+2 V not to exceed 4.6 V maximum, with a pulse width not to exceed 20% tKC.
3. VIHQ (max) is voltage on VDDQ pins plus 0.3 V.
VDDQ2 Range Logic Levels
Parameter
Symbol
Min.
Typ.
Max.
Unit
Notes
VDD Input High Voltage
VIH
0.6*VDD
—
VDD + 0.3
V
1
VDD Input Low Voltage
VIL
–0.3
—
0.3*VDD
V
1
VDDQ I/O Input High Voltage
VIHQ
0.6*VDD
—
VDDQ + 0.3
V
1,3
VDDQ I/O Input Low Voltage
VILQ
–0.3
—
0.3*VDD
V
1,3
Notes:
1. The part numbers of Industrial Temperature Range versions end the character “I”. Unless otherwise noted, all performance specifications quoted are evaluated for worst case in the temperature range marked on the device.
2. Input Under/overshoot voltage must be –2 V > Vi < VDDn+2 V not to exceed 4.6 V maximum, with a pulse width not to exceed 20% tKC.
3. VIHQ (max) is voltage on VDDQ pins plus 0.3 V.
Recommended Operating Temperatures
Parameter
Symbol
Min.
Typ.
Max.
Unit
Notes
Ambient Temperature (Commercial Range Versions)
TA
0
25
70
°C
2
Ambient Temperature (Industrial Range Versions)
TA
–40
25
85
°C
2
Notes:
1. The part numbers of Industrial Temperature Range versions end the character “I”. Unless otherwise noted, all performance specifications quoted are evaluated for worst case in the temperature range marked on the device.
2. Input Under/overshoot voltage must be –2 V > Vi < VDDn+2 V not to exceed 4.6 V maximum, with a pulse width not to exceed 20% tKC.
Rev: 1.04 2/2005
11/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Undershoot Measurement and Timing
Overshoot Measurement and Timing
VIH
20% tKC
VDD + 2.0 V
VSS
50%
50%
VDD
VSS – 2.0 V
20% tKC
VIL
Capacitance
(TA = 25oC, f = 1 MHZ, VDD = 2.5 V)
Parameter
Symbol
Test conditions
Typ.
Max.
Unit
Input Capacitance
CIN
VIN = 0 V
4
5
pF
Input/Output Capacitance
CI/O
VOUT = 0 V
6
7
pF
Note:
These parameters are sample tested.
AC Test Conditions
Parameter
Conditions
Input high level
VDD – 0.2 V
Input low level
0.2 V
Input slew rate
1 V/ns
Input reference level
VDD/2
Output reference level
VDDQ/2
Output load
Fig. 1
Notes:
1. Include scope and jig capacitance.
2. Test conditions as specified with output loading as shown in Fig. 1
unless otherwise noted.
3. Device is deselected as defined by the Truth Table.
Output Load 1
DQ
50Ω
30pF*
VDDQ/2
* Distributed Test Jig Capacitance
Rev: 1.04 2/2005
12/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
DC Electrical Characteristics
Parameter
Symbol
Test Conditions
Min
Max
Input Leakage Current
(except mode pins)
IIL
VIN = 0 to VDD
–1 uA
1 uA
ZZ Input Current
IIN1
VDD ≥ VIN ≥ VIH
0 V ≤ VIN ≤ VIH
–1 uA
–1 uA
1 uA
100 uA
Input Current
IIN2
VDD ≥ VIN ≥ VIL
0 V ≤ VIN ≤ VIL
–100 uA
–1 uA
1 uA
1 uA
Output Leakage Current
IOL
Output Disable, VOUT = 0 to VDD
–1 uA
1 uA
Output High Voltage
VOH2
IOH = –8 mA, VDDQ = 2.375 V
1.7 V
—
Output High Voltage
VOH3
IOH = –8 mA, VDDQ = 3.135 V
2.4 V
—
Output Low Voltage
VOL
IOL = 8 mA
—
0.4 V
Operating Currents
-333
-200
0
to
70°C
–40
to
85°C
0
to
70°C
–40
to
85°C
0
to
70°C
–40
to
85°C
0
to
70°C
–40
to
85°C
IDD
380
55
390
55
345
50
355
50
290
40
300
40
240
30
250
30
mA
IDDQ
380
55
390
55
345
05
355
50
290
40
300
40
240
30
250
30
mA
Pipeline
ISB
40
50
40
50
40
50
40
50
mA
Pipeline
IDD
85
90
80
85
85
90
75
80
mA
Test Conditions
Operating
Current
Device Selected;
All other inputs
≥VIH or ≤ VIL
Output open
(x36)
Pipeline
(x36)
Pipeline
2.5 V
Device Selected;
All other inputs
≥VIH or ≤ VIL
Output open
Standby
Current
ZZ ≥ VDD – 0.2 V
—
Deselect
Current
Device Deselected;
All other inputs
≥ VIH or ≤ VIL
—
Operating
Current
-250
Symbol
Parameter
3.3 V
-300
Mode
IDDQ
IDD
Unit
Notes:
1. IDD and IDDQ apply to any combination of VDD3, VDD2, VDDQ3, and VDDQ2 operation.
2. All parameters listed are worst case scenario.
Rev: 1.04 2/2005
13/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
AC Electrical Characteristics
Pipeline
Parameter
Symbol
Clock Cycle Time
-333
-300
-250
-200
Unit
Min
Max
Min
Max
Min
Max
Min
Max
tKC
3.0
—
3.3
—
4.0
—
5.0
—
ns
Clock to Output Valid
tKQ
—
2.0
—
2.2
—
2.3
—
2.7
ns
Clock to Output Invalid
tKQX
1.0
—
1.0
—
1.0
—
1.0
—
ns
Clock to Output in Low-Z
tLZ1
1.0
—
1.0
—
1.0
—
1.0
—
ns
Setup time
tS
1.0
—
1.1
—
1.2
—
1.4
—
ns
Hold time
tH
0
—
0.1
—
0.2
—
0.4
—
ns
G to Output Valid
tOE
—
2.0
—
2.2
—
2.3
—
2.5
ns
G to output in High-Z
tOHZ1
—
2.0
—
2.2
—
2.3
—
2.5
ns
Clock HIGH Time
tKH
1.3
—
1.3
—
1.3
—
1.3
—
ns
Clock LOW Time
tKL
1.5
—
1.5
—
1.5
—
1.5
—
ns
Clock to Output in
High-Z
tHZ1
1.0
2.0
1.0
2.2
1.5
2.3
1.5
3.0
ns
G to output in Low-Z
tOLZ1
0
—
0
—
0
—
0
—
ns
ZZ setup time
tZZS2
5
—
5
—
5
—
5
—
ns
ZZ hold time
tZZH2
1
—
1
—
1
—
1
—
ns
ZZ recovery
tZZR
20
—
20
—
20
—
20
—
ns
Notes:
1. These parameters are sampled and are not 100% tested.
2. ZZ is an asynchronous signal. However, in order to be recognized on any given clock cycle, ZZ must meet the specified setup and hold
times as specified above.
Rev: 1.04 2/2005
14/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Pipeline Mode Timing (+1)
Begin
Read A
Cont
Cont
Deselect Write B
Read C
Read C+1 Read C+2 Read C+3 Cont
Deselect
tKC
tKH tKL
CK
ADSP
tS
ADSC initiated read
tH
ADSC
tS
tH
ADV
tS
tH
A0–An
A
B
C
tS
GW
tS
tH
BW
tH
tS
Ba–Bd
tS
Deselected with E1
tH
E1
tS
E2 and E3 only sampled with ADSC
tH
E2
tS
tH
E3
G
tS
tOE
DQa–DQd
Rev: 1.04 2/2005
tOHZ
Q(A)
tH
D(B)
tKQ
tLZ
tKQX
tHZ
Q(C)
Q(C+1)
15/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
Q(C+2)
Q(C+3)
© 2002, GSI Technology
GS88037BT-333/300/250/200
Sleep Mode
During normal operation, ZZ must be pulled low, either by the user or by its internal pull down resistor. When ZZ is pulled high,
the SRAM will enter a Power Sleep mode after 2 cycles. At this time, internal state of the SRAM is preserved. When ZZ returns to
low, the SRAM operates normally after ZZ recovery time.
Sleep mode is a low current, power-down mode in which the device is deselected and current is reduced to ISB2. The duration of
Sleep mode is dictated by the length of time the ZZ is in a High state. After entering Sleep mode, all inputs except ZZ become
disabled and all outputs go to High-Z The ZZ pin is an asynchronous, active high input that causes the device to enter Sleep mode.
When the ZZ pin is driven high, ISB2 is guaranteed after the time tZZI is met. Because ZZ is an asynchronous input, pending
operations or operations in progress may not be properly completed if ZZ is asserted. Therefore, Sleep mode must not be initiated
until valid pending operations are completed. Similarly, when exiting Sleep mode during tZZR, only a Deselect or Read commands
may be applied while the SRAM is recovering from Sleep mode.
Sleep Mode Timing Diagram
tKH
tKC
tKL
CK
Setup
Hold
ADSP
ADSC
tZZR
tZZS
tZZH
ZZ
Application Tips
Single and Dual Cycle Deselect
SCD devices (like this one) force the use of “dummy read cycles” (read cycles that are launched normally but that are ended with
the output drivers inactive) in a fully synchronous environment. Dummy read cycles waste performance but their use usually
assures there will be no bus contention in transitions from reads to writes or between banks of RAMs. DCD SRAMs do not waste
bandwidth on dummy cycles and are logically simpler to manage in a multiple bank application (wait states need not be inserted at
bank address boundary crossings) but greater care must be exercised to avoid excessive bus contention.
Rev: 1.04 2/2005
16/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
TQFP Package Drawing (Package T)
L
Min. Nom. Max
A1
Standoff
0.05
0.10
0.15
A2
Body Thickness
1.35
1.40
1.45
b
Lead Width
0.20
0.30
0.40
c
Lead Thickness
0.09
—
0.20
D
Terminal Dimension
21.9
22.0
22.1
D1
Package Body
19.9
20.0
20.1
E
Terminal Dimension
15.9
16.0
16.1
E1
Package Body
13.9
14.0
14.1
e
Lead Pitch
—
0.65
—
L
Foot Length
0.45
0.60
0.75
L1
Lead Length
—
1.00
—
Y
Coplanarity
θ
Lead Angle
e
D
D1
Description
c
Pin 1
Symbol
L1
θ
b
A1
A2
0.10
Y
0°
—
7°
E1
E
Notes:
1. All dimensions are in millimeters (mm).
2. Package width and length do not include mold protrusion.
Rev: 1.04 2/2005
17/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
Ordering Information for GSI Synchronous Burst RAMs
Org
Part Number1
Type
Package
Speed2
(MHz/ns)
TA3
256K x 36
GS88037BT-333
Pipeline
TQFP
333
C
256K x 36
GS88037BT-300
Pipeline
TQFP
300
C
256K x 36
GS88037BT-250
Pipeline
TQFP
250
C
256K x 36
GS88037BT-200
Pipeline
TQFP
200
C
256K x 36
GS88037BT-333I
Pipeline
TQFP
333
I
256K x 36
GS88037BT-300I
Pipeline
TQFP
300
I
256K x 36
GS88037BT-250I
Pipeline
TQFP
250
I
256K x 36
GS88037BT-200I
Pipeline
TQFP
200
I
256K x 36
GS88037BGT-333
Pipeline
Pb-free TQFP
333
C
256K x 36
GS88037BGT-300
Pipeline
Pb-free TQFP
300
C
256K x 36
GS88037BGT-250
Pipeline
Pb-free TQFP
250
C
256K x 36
GS88037BGT-200
Pipeline
Pb-free TQFP
200
C
256K x 36
GS88037BGT-333I
Pipeline
Pb-free TQFP
333
I
256K x 36
GS88037BGT-300I
Pipeline
Pb-free TQFP
300
I
256K x 36
GS88037BGT-250I
Pipeline
Pb-free TQFP
250
I
256K x 36
GS88037BGT-200I
Pipeline
Pb-free TQFP
200
I
Status
Notes:
1. Customers requiring delivery in Tape and Reel should add the character “T” to the end of the part number. Example: GS88037BT-200IT.
2. TA = C = Commercial Temperature Range. TA = I = Industrial Temperature Range.
3. GSI offers other versions this type of device in many different configurations and with a variety of different features, only some of which are
covered in this data sheet. See the GSI Technology web site (www.gsitechnology.com) for a complete listing of current offerings.
Rev: 1.04 2/2005
18/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology
GS88037BT-333/300/250/200
9Mb Sync SRAM Datasheet Revision History
DS/DateRev. Code: Old;
New
Types of Changes
Format or Content
• Creation of new datasheet
88037B_r1
88037B_r1; 88037B_r1_01
Content
88037B_r1_01;
88037B_r1_02
Content/Format
88037B_r1_02;
88037B_r1_03
Content/Format
88037B_r1_03;
88037B_r1_04
Content
Rev: 1.04 2/2005
Page;Revisions;Reason
• Corrected ordering information (incorrect speed bins
corrected)
• Updated format
• Deleted unneeded speed bins (275 & 225 MHz)
• Added Pb-free information for TQFP
• Removed erroneous numeral from address pin (Pin 48)
19/19
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology