![]() |
|
If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
Datasheet File OCR Text: |
GALVANTECH, INC. GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM SYNCHRONOUS BURST SRAM PIPELINED OUTPUT FEATURES * * * * * * * * * * * * * * * * * * * * Fast access times: 5, 6, 7, and 8ns Fast clock speed: 100, 83, 66, and 50 MHz Provide high performance 3-1-1-1 access rate Fast OE# access times: 5, and 6ns Optimal for performance(twoe cycle chip deselect, depth expansion without wait state) Single +3.3V -5 to +10% power supply 5V tolerant inputs except I/O's Clamp diodes to VSSQ at all inputs and outputs Common data inputs and data outputs BYTE WRITE ENABLE and GLOBAL WRITE control Three chip enables for depth expansion and address pipeline Address, control, input, and output pipeline registers Internally self-timed WRITE CYCLE WRITE pass-through capability Burst control pins (interleaved or linear burst sequence) Automatic power-down for portable applications High density, high speed packages Low capacitive bus loading High 30pF output drive capability at rated access time 64K x 18 SRAM +3.3V SUPPLY,FULLY REGISTERED INPUTS AND OUTPUTS, BURST COUNTER GENERAL DESCRIPTION The Galvantech Synchronous Burst SRAM family employs high-speed, low power CMOS designs using advanced double-layer polysilicon, double-layer metal technology. Each memory cell consists of four transistors and two high valued resistors. The GVT7164C18 SRAM integrates 65536x18 SRAM cells with advanced synchronous peripheral circuitry and a 2bit counter for internal burst operation. All synchronous inputs are gated by registers controlled by a positive-edgetriggered clock input (CLK). The synchronous inputs include all addresses, all data inputs, address-pipelining chip enable (CE#), depth-expansion chip enables (CE2# and CE2), burst control inputs (ADSC#, ADSP#, and ADV#), write enables (WEL#, WEH#, and BWE#), and global write (GW#). Asynchronous inputs include the output enable (OE#) and burst mode control (MODE). The data outputs (Q), enabled by OE#, are also asynchronous. Addresses and chip enables are registered with either address status processor (ADSP#) or address status controller (ADSC#) input pins. Subsequent burst addresses can be internally generated as controlled by the burst advance pin (ADV#). Address, data inputs, and write controls are registered onchip to initiate self-timed WRITE cycle. WRITE cycles can be one to four bytes wide as controlled by the write control inputs. Individual byte write allows individual byte to be written. WEL# controls DQ1-DQ8 and DQP1. WEH# controls DQ9-DQ16 and DQP2. WEL#, and WEH# can be active only with BWE# being LOW. GW# being LOW causes all bytes to be written. This device also incorporates WRITE pass-through capability and pipelined enable circuit for better system performance. The GVT7164C18 operates from a +3.3V power supply. All inputs and outputs are TTL-compatible. The device is ideally suited for 486, PentiumTM, 680x0, and PowerPCTM systems and for systems that are benefited from a wide synchronous data bus. OPTIONS Timing 5ns access/10ns cycle 6ns access/12ns cycle 7ns access/15ns cycle 8ns access/20ns cycle Packages 100-pin PQFP MARKING -5 -6 -7 -8 Q * Galvantech, Inc. 3080 Oakmead Village Drive, Santa Clara, CA 95051 Tel (408) 566-0688 Fax (408) 566-0699 Web Site http://www.galvantech.com Rev. 2/98 Pentium is a trademark of Intel Corporation. PowerPC is a trademark of IBM Corporation. Galvantech, Inc. reserves the right to change products or specifications without notice. GALVANTECH, INC. FUNCTIONAL BLOCK DIAGRAM GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM WEH# * BWE# UPPER BYTE WRITE D Q WEL# * GW# CE# * CE2 * CE2# ZZ OE# ADSP# Power Down Logic LOWER BYTE WRITE D Q lo byte write hi byte write Output Buffers ENABLE D Q D Q Input Register A15-A2 ADSC# Address Register 64K x 9 x 2 SRAM Array OUTPUT REGISTER CLR ADV# A1-A0 * MODE Binary Counter & Logic D Q DQ1DQ16, DQP1, DQP2 NOTE: The Functional Block Diagram illustrates simplified device operation. See Truth Table, pin descriptions and timing diagrams for detailed information. February 6, 1998 2 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM PIN ASSIGNMENT (Top View) A6 A7 CE# CE2 NC NC WEH# WEL# CE2# VCC VSS CLK GW# BWE# OE# ADSC# ADSP# ADV# A8 A9 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 NC NC NC VCCQ VSSQ NC NC DQ9 DQ10 VSSQ VCCQ DQ11 DQ12 VCC VCC NC VSS DQ13 DQ14 VCCQ VSSQ DQ15 DQ16 DQP2 NC VSSQ VCCQ NC NC NC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 100-pin PQFP or 100-pin TQFP 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 A10 NC NC VCCQ VSSQ NC DQP1 DQ8 DQ7 VSSQ VCCQ DQ6 DQ5 VSS NC VCC ZZ DQ4 DQ3 VCCQ VSSQ DQ2 DQ1 NC NC VSSQ VCCQ NC NC NC 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 PIN DESCRIPTIONS QFP PINS 37, 36, 35, 34, 33, 32, 100, 99, 82, 81, 80, 48, 47, 46, 45, 44 93, 94 SYMBO L A0-A15 TYPE Input- Addresses: These inputs are registered and must meet the setup and hold addresses associated with A0 and A1, during burst cycle and wait cycle. Synchronous times around the rising edge of CLK. The burst counter generates internal WEL#, WEH# Input- Byte Write Enables: A byte write enable is LOW for a WRITE cycle and controls DQ9-DQ16 and DQP2. Data I/O are high impedance if either of these inputs are LOW, conditioned by BWE# being LOW. Synchronous HIGH for a READ cycle. WEL# controls DQ1-DQ8 and DQP1. WEH# 87 88 BWE# GW# InputInput- Write Enable: This active LOW input gates byte write operations and must Global Write: This active LOW input allows a full 18-bit WRITE to occur hold times around the rising edge of CLK. Synchronous meet the setup and hold times around the rising edge of CLK. Synchronous independent of the BWE# and WEn# lines and must meet the setup and 89 CLK Clock: This signal registers the addresses, data, chip enables, write control Synchronous and burst control inputs on its rising edge. All synchronous inputs must meet setup and hold times around the clock's rising edge. InputInputSynchronous Input- 98 92 CE# CE2# Chip Enable: This active LOW input is used to enable the device and to gate Chip Enable: This active LOW input is used to enable the device. Synchronous ADSP#. MODE A5 A4 A3 A2 A1 A0 NC NC VSS VCC NC NC A15 A14 A13 A12 A11 NC NC DESCRIPTION February 6, 1998 3 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. PIN DESCRIPTIONS (continued) QFP PINS 97 86 83 GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM SYMBOL CE2 OE# ADV# TYPE inputSynchronous DESCRIPTION Chip enable: This active HIGH input is used to enable the device. Output Enable: This active LOW asynchronous input enables the data output drivers. Address Advance: This active LOW input is used to control the internal advance). Input Input- Synchronous burst counter. A HIGH on this pin generates wait cycle (no address 84 ADSP# Input- Address Status Processor: This active LOW input, along with CE# being is initiated using the new address. Synchronous LOW, causes a new external address to be registered and a READ cycle 85 ADSC# Input- Address Status Controller: This active LOW input causes device to be deREAD or WRITE cycle is initiated depending upon write control inputs. Synchronous selected or selected along with new external address to be registered. A 31 64 58, 59, 62, 63, 68, 69, 72, 73, 8, 9, 12, 13, 18, 19, 22, 23 74, 24 14, 15, 41,65, 91 17, 40, 67, 90 4, 11, 20, 27, 54, 61, 70, 77 5, 10, 21, 26, 55, 60, 71, 76 1-3, 6, 7, 16, 25, 2830, 38, 39, 42, 43, 49-53,56, 57, 66, 75, 78-79, 95, 96 MODE ZZ DQ1-DQ16 InputStatic Input/ Output Input/ Output Supply Ground Mode: This input selects the burst sequence. A LOW on this pin selects linear burst. A NC or HIGH on this pin selects interleaved burst. Data Inputs/Outputs: Low Byte is DQ1-DQ8. HIgh Byte is DQ9-DQ16. Input data must meet setup and hold times around the rising edge of CLK. Parity Inputs/Outputs: DQP1 is parity bit for DQ1-DQ8 and DQP2 is parity bit for DQ9-DQ16. Power Supply: +3.3V -5 to +10% Ground: GND Input-Static Snooze: LOW or NC for normal operation. High for low power standby. DQP1, DQP2 VCC VSS VCCQ VSSQ NC I/O Supply Output Buffer Supply: +3.3V -5 to +10% I/O Ground Output Buffer Ground: GND No Connect: These signals are not internally connected. BURST ADDRESS TABLE (MODE = NC/VCC) First Address (external) A...A00 A...A01 A...A10 A...A11 Second Address (internal) A...A01 A...A00 A...A11 A...A10 Third Address (internal) A...A10 A...A11 A...A00 A...A01 Fourth Address (internal) A...A11 A...A10 A...A01 A...A00 BURST ADDRESS TABLE (MODE =GND) First Address (external) A...A00 A...A01 A...A10 A...A11 Second Address (internal) A...A01 A...A10 A...A11 A...A00 Third Address (internal) A...A10 A...A11 A...A00 A...A01 Fourth Address (internal) A...A11 A...A00 A...A01 A...A10 PARTIAL TRUTH TABLE FOR READ/WRITE FUNCTION READ READ WRITE one byte GW# H H H BWE# H L L WEL# X H L WEH# X H H February 6, 1998 4 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. FUNCTION WRITE all bytes WRITE all bytes GW# H L BWE# L X WEL# L X GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM WEH# L X TRUTH TABLE OPERATION ADDRESS USED CE# CE2# CE2 ADSP# ADSC# ADV# WRITE# OE# CLK DQ Deselected Cycle, Power Down Deselected Cycle, Power Down Deselected Cycle, Power Down Deselected Cycle, Power Down Deselected Cycle, Power Down READ Cycle, Begin Burst READ Cycle, Begin Burst WRITE Cycle, Begin Burst READ Cycle, Begin Burst READ Cycle, Begin Burst READ Cycle, Continue Burst READ Cycle, Continue Burst READ Cycle, Continue Burst READ Cycle, Continue Burst WRITE Cycle, Continue Burst WRITE Cycle, Continue Burst READ Cycle, Suspend Burst READ Cycle, Suspend Burst READ Cycle, Suspend Burst READ Cycle, Suspend Burst WRITE Cycle, Suspend Burst WRITE Cycle, Suspend Burst None None None None None External External External External External Next Next Next Next Next Next Current Current Current Current Current Current H L L L L L L L L L X X H H X H X X H H X H X X H X H L L L L L X X X X X X X X X X X X X L X L X H H H H H X X X X X X X X X X X X X L L H H L L H H H H H X X H X H H X X H X L X X L L X X L L L H H H H H H H H H H H H X X X X X X X X X X L L L L L L H H H H H H X X X X X X X L H H H H H H L L H H H H L L X X X X X L H X L H L H L H X X L H L H X X L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H L-H High-Z High-Z High-Z High-Z High-Z Q High-Z D Q High-Z Q High-Z Q High-Z D D Q High-Z Q High-Z D D Note: 1. 2. 3. 4. 5. 6. 7. X means "don't care." H means logic HIGH. L means logic LOW. WRITE# = L means [BWE# + WEL#*WEH#]*GW# equals LOW. WRITE# = H means [BWE# + WEL#*WEH#]*GW# equals HIGH. WEL# enables write to DQ1-DQ8 and DQP1. WEH# enables write to DQ9-DQ16 and DQP2. All inputs except OE# must meet setup and hold times around the rising edge (LOW to HIGH) of CLK. Suspending burst generates wait cycle. For a write operation following a read operation, OE# must be HIGH before the input data required setup time plus High-Z time for OE# and staying HIGH throughout the input data hold time. This device contains circuitry that will ensure the outputs will be in High-Z during power-up. ADSP# LOW along with chip being selected always initiates an READ cycle at the L-H edge of CLK. A WRITE cycle can be performed by setting WRITE# LOW for the CLK L-H edge of the subsequent wait cycle. Refer to WRITE timing diagram for clarification. PASS-THROUGH TRUTH TABLE PREVIOUS CYCLE OPERATION BWn# OPERATION PRESENT CYCLE CE# BWn# OE# NEXT CYCLE OPERATION Initiate WRITE cycle, all bytes Address = A(n-1), data = D(n-1) Initiate WRITE cycle, all bytes Address = A(n-1), data = D(n-1) Initiate WRITE cycle, all bytes Address = A(n-1), data = D(n-1) Initiate WRITE cycle, one byte Address = A(n-1), data = D(n-1) All L2,3 All L2,3 All L2,3 One L2 Initiate READ cycle Register A(n), Q = D(n-1) No new cycle Q = D(n-1) No new cycle Q = HIGH-Z No new cycle Q = D(n-1) for one byte L H H H H H H H L L H L Read D(n) No carry-over from previous cycle No carry-over from previous cycle No carry-over from previous cycle February 6, 1998 5 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. ABSOLUTE MAXIMUM RATINGS* GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM *Stresses greater than those listed uunder "Absolute Maximum Ratings" may cause permanent damage to the device.This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Voltage on VCC Supply Relative to VSS........-0.5V to +4.6V VIN .....................................................................-0.5V to +6V Storage Temperature (plastic) .......................-55oC to +150o Junction Temperature ....................................................+150o Power Dissipation ...........................................................1.6W Short Circuit Output Current ......................................100mA DC ELECTRICAL CHARACTERISTICS AND RECOMMENDED OPERATING CONDITIONS (0oC Ta 70C; VCC = 3.3V -5 to +10% unless otherwise noted) CONDITIONS SYMBOL VIH VIl 0V < VIN < VCC Output(s) disabled, 0V < VOUT < VCC IOH = -4.0mA IOL = 8.0mA ILI ILO VOH VOL VCC 3.1 DESCRIPTION Input High (Logic 1) voltage Input Low (Logic 0) Voltage Input Leakage Current Output Leakage Current Output High Voltage Output Low Voltage Supply Voltage MIN 2.0 -0.3 -2 -2 2.4 MAX VCCQ+0.3 0.8 2 2 UNITS V V uA uA V NOTES 1,2 1, 2 14 1, 11 1, 11 1 0.4 3.6 V V DESCRIPTION Power Supply Current: Operating Power Supply Current: Idle CONDITIONS Device selected; all inputs < VILor > VIH;cycle time > tKC MIN; VCC =MAX; outputs open Device selected; ADSC#, ADSP#, ADV#, GW#, BWE# >VIH ; all other inputs < VILor > VIH; VCC = MAX; cycle time > tKC MIN; outputs open Device deselected; VCC = MAX; all inputs < VSS +0.2 or >VCC -0.2; all inputs static; CLK frequency = 0 Device deselected; all inputs < VIL or > VIH ; all inputs static; VCC = MAX; CLK frequency = 0 Device deselected; all inputs < VIL or > VIH; VCC = MAX; CLK cycle time > tKC MIN SYM Icc TYP 180 -5 360 -6 315 -7 270 -8 225 UNITS NOTES mA 3, 12, 13 12,13 ISB1 30 60 55 50 45 mA CMOS Standby ISB2 0.2 2 2 2 2 mA 12,13 TTL Standby ISB3 8 18 18 18 18 mA 12,13 Clock Running ISB4 30 60 55 50 45 mA 12,13 CAPACITANCE DESCRIPTION Input Capacitance Input/Output Capacitance (DQ) CONDITIONS TA = 25oC; f = 1 MHz VCC = 3.3V SYMBOL CI CO TYP 3 6 MAX 4 7 UNITS pF pF NOTES 4 4 THERMAL CONSIDERATION DESCRIPTION Thermal Resistance - Junction to Ambient Thermal Resistance - Junction to Case CONDITIONS Still air, soldered on 4.25 x 1.125 inch 4-layer PCB SYMBOL JA JC PLCC TYP TQFP TYP TBD 3 20 1 UNITS oC/W oC/W NOTES February 6, 1998 6 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. AC ELECTRICAL CHARACTERISTICS (Note 5) (0oC GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM TA 70oC; VCC = 3.3V -5 to +10%) -5 SYM tKC tKH tKL tKQ tKQX tKQLZ tKQHZ tOEQ tOELZ tOEHZ tS tH DESCRIPTION Clock Clock cycle time Clock HIGH time Clock LOW time Output Times Clock to output valid Clock to output invalid Clock to output in Low-Z Clock to output in High-Z OE to output valid OE to output in Low-Z OE to output in High-Z Setup Times Address, Controls and Data In Hold Times Address, Controls and Data In -6 MAX MIN MAX MIN -7 MAN MIN -8 MAN UNITS NOTES MIN 10 4 4 5 2 3 5 5 0 4 2.5 0.5 12 4 4 6 2 3 5 5 0 5 2.5 0.5 15 5 5 7 2 3 6 5 0 6 2.5 0.5 20 6 6 8 2 3 6 6 0 6 3 0.5 ns ns ns ns ns ns ns ns ns ns ns ns 6,7 6,7 9 6,7 6,7 10 10 CAPACITANCE DERATING DESCRIPTION Clock to output valid SYMBOL tKQ TYP 0.016 MAX UNITS ns / pF NOTES 15 February 6, 1998 7 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. AC TEST CONDITIONS Input pulse levels Input rise and fall times Input timing reference levels Output reference levels Output load 0V to 3.0V 1.5ns 1.5V 1.5V See Figures 1 and 2 GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM OUTPUT LOADS DQ Z0 = 50 50 Vt = 1.5V Fig. 1 OUTPUT LOAD EQUIVALENT 3.3v 317 DQ 351 5 pF 30 pF Fig. 2 OUTPUT LOAD EQUIVALENT NOTES 1. 2. 3. 4. 5. 6. 7. 8. All voltages referenced to VSS (GND). Overshoot: Undershoot: VIH +6.0V for t tKC /2. VIL -2.0V for t tKC /2 15. Capacitance derating applies to capacitance different from the load capacitance shown in Fig. 1. Icc is given with no output current. Icc increases with greater output loading and faster cycle times. This parameter is sampled. Test conditions as specified with the output loading as shown in Fig. 1 unless otherwise noted. Output loading is specified with CL=5pF as in Fig. 2. At any given temperature and voltage condition, tKQHZ is less than tKQLZ and tOEHZ is less than tOELZ. A READ cycle is defined by byte write enables all HIGH or ADSP# LOW along with chip enables being active for the required setup and hold times. A WRITE cycle is defined by at one byte or all byte WRITE per READ/WRITE TRUTH TABLE. OE# is a "don't care" when a byte write enable is sampled LOW. 9. 10. This is a synchronous device. All synchronous inputs must meet specified setup and hold time, except for "don't care" as defined in the truth table. 11. AC I/O curves are available upon request. 12. "Device Deselected" means the device is in POWER -DOWN mode as defined in the truth table. "Device Selected" means the device is active. 13. Typical values are measured at 3.3V, 25oC and 20ns cycle time. 14. MODE pin has an internal pull-up and ZZ pin has an internal pull-down. These two pins exhibit an input leakage current of +30 A. February 6, 1998 8 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. t GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM READ TIMING KC tKL CLK t S t KH ADSP# t H ADSC# tS ADDRESS WEL#, WEH#, BWE#, GW# CE# (See Note) A1 tH A2 t S ADV# tH OE# tKQ tKQLZ tOELZ tOEQ tKQ DQ Q(A1) Q(A2) Q(A2+1) Q(A2+2) Q(A2+3) Q(A2) Q(A2+1) SINGLE READ BURST READ Note: CE# active in this timing diagram means that all chip enables CE#, CE2, and CE2# are active. February 6, 1998 9 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM WRITE TIMING CLK tS ADSP# tH ADSC# tS ADDRESS WEL#, WEH#, BWE# GW# CE# (See Note) A1 tH A2 A3 tS ADV# tH OE# tOEHZ tKQX DQ Q D(A1) D(A2) D(A2+1) D(A2+1) D(A2+2) D(A2+3) D(A3) D(A3+1) D(A3+2) SINGLE WRITE BURST WRITE BURST WRITE Note: CE# active in this timing diagram means that all chip enables CE#, CE2, and CE2# are active. February 6, 1998 10 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM READ/WRITE TIMING CLK tS ADSP# tH ADSC# tS ADDRESS WEL#, WEH#, BWE#, GW# CE# (See Note) ADV# A1 A2 tH A3 A4 A5 OE# DQ Q(A1) Single Reads Q(A2) D(A3) Single Write Q(A3) Pass Through Q(A4) Q(A4+1) Burst Read Q(A4+2) D(A5) D(A5+1) Burst Write Note: CE# active in this timing diagram means that all chip enables CE#, CE2, and CE2# are active. February 6, 1998 11 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. 100 Pin PQFP Package Dimensions GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM 17.20 + 0.30 14.00 + 0.10 #1 20.00 + 0.10 23.20 + 0.30 2.80 + 0.25 0.65 Basic Note: All dimensions in Millimeters 0.30 + 0.10 February 6, 1998 12 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 GALVANTECH, INC. Ordering Information GVT7164C18 64K X 18 SYNCHRONOUS BURST SRAM GVT 7164C18 X - XX Galvantech Prefix Part Number Speed (5 = 5ns access/10ns cycle 6 = 6ns access/12ns cycle 7 = 7ns access/15ns cycle, 8= 8ns access/20ns cycle) Package (Q = 100 PIN PQFP) February 6, 1998 13 Galvantech, Inc. reserves the right to change products or specifications without notice. Rev. 2/98 |
Price & Availability of GVT7164C18
![]() |
|
|
All Rights Reserved © IC-ON-LINE 2003 - 2022 |
[Add Bookmark] [Contact Us] [Link exchange] [Privacy policy] |
Mirror Sites : [www.datasheet.hk]
[www.maxim4u.com] [www.ic-on-line.cn]
[www.ic-on-line.com] [www.ic-on-line.net]
[www.alldatasheet.com.cn]
[www.gdcy.com]
[www.gdcy.net] |