Sanyo LC35256FT-70U Specifications

Ordering number : ENN*6302

52600RM (OT) No. 6302-1/7

Overview

The LC35256FM and LC35256FT are asynchronous
silicon-gate CMOS SRAMs with a 32K-word by 8-bit
structure. These are full-CMOS devices with 6 transistors
per memory cell, and feature low-voltage operation, a low
operating current drain, and an ultralow standby current.
Control inputs include OE for fast memory access and CE
(chip enable) for power saving and device selection. This
makes these devices optimal for systems that require low
power or battery backup, and makes memory expansion
easy. The ultralow standby current allows these devices to
be used with capacitor backup as well.

Features

• Supply voltage range: 4.5 to 5.5 V

• Access time at 5 V operation:
LC35256FM, FT-55U: 55 ns (maximum)
LC35256FM, FT-70U: 70 ns (maximum)

• Standby current: 3.0 µA (Ta ≤ 70°C)

5.0 µA (Ta ≤ 85°C)

• Operating temperature: –40 to +85°C

• Data retention voltage: 2.0 to 5.5 V

• All I/O levels: TTL compatible

• Input/output shared function pins, 3-state output pins

• No clock required

• Package
28-pin SOP (450 mil) plastic package: LC35256FM
28-pin TSOP (8 × 13.4 mm) plastic package: LC35256FT

Package Dimensions

unit: mm

3187A-SOP28D

unit: mm

3221-TSOP28 (Type I)

Preliminary

LC35256FM, FT-55U/70U

SANYO Electric Co.,Ltd. Semiconductor Company

TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN

256K (32768 words × 8 bits) SRAM

Control Pins: OE and CE

CMOS IC

1

14

15

28

11.8

1.0

8.4

9.8

18.0

0.1

2.3

1.27

0.4

0.15

SANYO: SOP28D

[LC35256FM]

Any and all SANYO products described or contained herein do not have specifications that can handle
applications that require extremely high levels of reliability, such as life-support systems, aircraft’s
control systems, or other applications whose failure can be reasonably expected to result in serious
physical and/or material damage. Consult with your SANYO representative nearest you before using
any SANYO products described or contained herein in such applications.

SANYO assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other
parameters) listed in products specifications of any and all SANYO products described or contained
herein.

SANYO: TSOP28 (Type I)

[LC35256FT]

21 8

1

22 7

28

0.2

0.55

8.1

11.8

1.27max

13.4

0.5

0.125

0.08

Pin Assignment (Top view)

No. 6302-2/7

LC35256FM, FT-55U/70U

OE 22

23
24
25
26
27
28

1
2
3
4
5
6
7

21
20
19
18
17
16
15
14
13
12
11
10

9
8

A

11

A

10

I/O

8

I/O

7

I/O

6

I/O

5

I/O

4

GND
I/O

3

I/O

2

I/O

1

A

0

A

1

A

2

CE

A

9

A

8

A

13

WE

V

CC

A

14

A

12

A

7

A

6

A

5

A

4

A

3

TSOP28

LC35256FT

1
2
3
4
5
6
7
8

9
10
11
12
13
14

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

A

14

V

CC

WE
A

13

A

8

A

9

A

11

OE
A

10

CE
I/O

8

I/O

7

I/O

6

I/O

5

I/O

4

A

12

A

7

A

6

A

5

A

4

A

3

A

2

A

1

A

0

I/O

1

I/O

2

I/O

3

GND

LC35256FM

SOP28D

Block Diagram

A

6

A

7

A

8

A

9

A

10

A

11

A

12

A

13

A

14

V

CC

GND

I/O

1

I/O

8

CE

WE

OE

A0A1A2A3A4A

5

Address buffer

Row decoder

Memory cell array

512 × 512

Column I/O

circuit

Column decoder

Address buffer

Output

data

buffer

Input data buffer

Input data

control circuit

Pin Functions

No. 6302-3/7

LC35256FM, FT-55U/70U

A0 to A14 Address input

WE Read/write control input
OE Output enable input

CE Chip enable input

I/O1 to I/O8 Data I/O

V

CC

, GND Power supply, ground

Function Table

Mode CE OE WE I/O Supply current

Read cycle L L H Data output I

CCA

Write cycle L X L Data input I

CCA

Output disable L H H High impedance I

CCA

Unselected H X X High impedance I

CCS

Parameter Symbol Conditions Ratings Unit

Maximum supply voltage V

CC

max 7.0 V

Input pin voltage V

IN

–0.3* to VCC+ 0.3 V

I/O pin voltage V

I/O

–0.3 to VCC+ 0.3 V
Operating temperature Topr –40 to +85 °C
Storage temperature Tstg –55 to +125 °C

Specifications

Absolute Maximum Ratings

Note: * The minimum value is –3.0 V for pulse widths under 30 ns.

I/O Capacitances at Ta = 25°C, f = 1 MHz

Parameter Symbol Conditions

Ratings

Unit

min typ max

I/O pin capacitance C

I/OVI/O

= 0 V 6 10 pF

Input pin capacitance C

I

VIN= 0 V 6 10 pF

Note: All units are not tested; only samples are tested.

DC Allowable Operating Ranges at Ta = –40 to +85°C, VCC= 4.5 to 5.5 V

Parameter Symbol Conditions

Ratings

Unit

min typ max

Supply voltage V

CC

4.5 5.0 5.5 V

Input voltage

V

IH

2.2

VCC+ 0.3

V

V

IL

–0.3* +0.8 V

Note: * The minimum value is –3.0 V for pulse widths under 30 ns.