E2L0012-17-Y1 ¡ Semiconductor MSM514252A ¡ Semiconductor This version: Jan. 1998 MSM514252A Previous version: Dec. 1996 262,144-Word ¥ 4-Bit Multiport DRAM DESCRIPTION The MSM514252A is an 1-Mbit CMOS multiport DRAM composed of a 262,144-word by 4-bit dynamic RAM, and a 512-word by 4-bit static serial access memory, SAM port. The RAM port and SAM port operate independently and asynchronously. The MSM514252A supports three types of operations: random access to and from the RAM port, high speed serial access to and from the SAM port and bidirectional transfer of data between any selected row in the RAM port and the SAM port. The RAM port and the SAM port can be accessed independently except when data is being transferred between them internally. FEATURES • Single power supply of 5 V ±10% with a built-in VBB generator • All inputs and outputs: TTL compatible • Multiport organization RAM port: 256K word ¥ 4 bits SAM port: 512 word ¥ 4 bits • RAM port Fast page mode, Read-modify-write CAS before RAS refresh, Hidden refresh RAS only refresh, Standard write-per-bit • SAM port High speed serial Read/Write capability Fully static register 512 tap location • RAM-SAM bidirectional, Read/Write/Pseudo write, Real time read transfer • Package options: 28-pin 400 mil plastic ZIP (ZIP28-P-400-1.27) (Product : MSM514252A-xxZS) 28-pin 400 mil plastic SOJ (SOJ28-P-400-1.27) (Product : MSM514252A-xxJS) xx indicates speed rank. PRODUCT FAMILY Family Access Time Cycle Time Power Dissipation RAM SAM RAM SAM Operating Standby MSM514252A-70 70 ns 25 ns 140 ns 30 ns 120 mA 8 mA MSM514252A-80 80 ns 25 ns 150 ns 30 ns 110 mA 8 mA MSM514252A-10 100 ns 25 ns 180 ns 30 ns 100 mA 8 mA 1/33 ¡ Semiconductor MSM514252A PIN CONFIGURATION (TOP VIEW) NC 1 W4/IO4 3 SIO3 5 VSS 7 SIO1 9 DT/OE 11 W2/IO2 13 NC 15 A8 17 A5 19 VCC 21 A3 23 A1 25 NC 27 2 W3/IO3 4 SE 6 SIO4 8 SC 10 SIO2 SC 1 28 VSS SIO1 2 27 SIO4 SIO2 3 26 SIO3 25 SE DT/OE 4 W1/IO1 5 24 W4/IO4 W2/IO2 6 23 W3/IO3 WB/WE 7 22 NC 12 W1/IO1 NC 8 21 CAS 14 WB/WE RAS 9 20 NC A8 10 19 A0 A6 11 18 A1 A5 12 17 A2 A4 13 16 A3 VCC 14 15 A7 16 RAS 18 A6 20 A4 22 A7 24 A2 26 A0 28-Pin Plastic SOJ 28 CAS 28-Pin Plastic ZIP Pin Name A0 - A8 Function Address Input RAS Row Address Strobe CAS Column Address Strobe DT/OE Data Transfer/Output Enable WB/WE Write per Bit/Write Enable W1/IO1 - W4/IO4 Write Mask/Data IN, OUT SC Serial Clock SE Serial Enable SIO1 - SIO4 VCC/VSS NC Serial Input/Output Power Supply (5 V) /Ground (0 V) No Connection 2/33 ¡ Semiconductor MSM514252A I/O Buffer (RAM) SIO1 - SIO4 SE SC WB/WE DT/OE CAS RAS W1/IO1 - W4/IO4 BLOCK DIAGRAM I/O Buffer (SAM) Timing Generator Mask Register SAM 512 ¥ 512 ¥ 4 Cell Array Column Address Buffer Row Address Buffer Serial Address Counter Row Decoder Selector Sense Amplifier Column Decoder Write/WPB Control Refresh Counter VCC A0 - A8 VSS 3/33 ¡ Semiconductor MSM514252A ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings Parameter (Note : 16) Unit Symbol Condition Rating Input Output Voltage VT Ta = 25°C –1.0 to 7.0 V Output Current lOS Ta = 25°C 50 mA Power Dissipation PD Ta = 25°C 1 W Operating Temperature Topr — 0 to 70 °C Storage Temperature Tstg — –55 to 150 °C Recommended Operating Conditions Parameter (Ta = 0°C to 70°C) (Note : 17) Symbol Min. Typ. Max. Unit Power Supply Voltage VCC 4.5 5.0 5.5 V Input High Voltage VIH 2.4 — 6.5 V Input Low Voltage VIL –1.0 — 0.8 V Capacitance Parameter (VCC = 5 V ±10%, f = 1 MHz, Ta = 25°C) Symbol Min. Max. Unit CI — 7 pF CI/O — 9 pF Input Capacitance Input / Output Capacitance Note : This parameter is periodically sampled and is not 100% tested. DC Characteristics 1 Symbol Condition Min. Max. Output "H" Level Voltage VOH IOH = –2 mA 2.4 — Output "L" Level Voltage VOL IOL = 2 mA — 0.4 Input Leakage Current ILI 0 £ VIN £ VCC All other pins not under test = 0 V –10 10 0 £ VOUT £ 5.5 V Output Disable –10 Parameter Output Leakage Current ILO Unit V mA 10 4/33 ¡ Semiconductor MSM514252A DC Characteristics 2 Item (RAM) Operating Current (RAS, CAS Cycling, tRC = tRC min.) (VCC = 5 V ±10%, Ta = 0°C to 70°C) SAM Symbol -70 -80 -10 Max. Max. Max. Unit Note Standby ICC1 85 75 65 1, 2 Active ICC1A 120 110 100 1, 2 Standby Current Standby ICC2 8 8 8 3 (RAS, CAS = VIH) Active ICC2A 50 45 40 1, 2 RAS Only Refresh Current (RAS Cycling, CAS = VIH, tRC = tRC min.) Page Mode Current (RAS = VIL, CAS Cycling, tPC = tPC min.) CAS before RAS Refresh Current (RAS Cycling, CAS before RAS, tRC = tRC min.) Data Transfer Current (RAS, CAS Cycling, tRC = tRC min.) Standby ICC3 85 75 65 1, 2 Active ICC3A 120 110 100 1, 2 Standby ICC4 70 65 60 Active ICC4A 120 110 100 mA 1, 2 1, 2 Standby ICC5 85 75 65 1, 2 Active ICC5A 120 110 100 1, 2 Standby ICC6 85 75 65 1, 2 Active ICC6A 120 110 100 1, 2 5/33 ¡ Semiconductor MSM514252A AC Characteristics (1/3) Parameter Random Read or Write Cycle Time Read Modify Write Cycle Time (VCC = 5 V ±10%, Ta = 0°C to 70°C) Note 4, 5, 6 Symbol -70 -80 -10 Min. Max. Min. Max. Min. Max. Unit Note tRC 140 — 150 — 180 — ns tRWC 195 — 195 — 235 — ns tPC 45 — 50 — 55 — ns tPRWC 90 — 90 — 100 — ns tRAC — 70 — 80 — 100 ns 7, 13 Access Time from Column Address tAA — 35 — 40 — 50 ns 7, 13 Access Time from CAS tCAC — 20 — 25 — 25 ns 7, 14 Access Time from CAS Precharge tCPA — 40 — 45 — 50 ns 7, 14 Output Buffer Turn-off Delay tOFF 0 20 0 20 0 20 ns 9 6 Fast Page Mode Cycle Time Fast Page Mode Read Modify Write Cycle Time Access Time from RAS Transition Time (Rise and Fall) tT 3 35 3 35 3 35 ns RAS Precharge Time tRP 60 — 60 — 70 — ns 100 RAS Pulse Width tRAS 70 10k 80 10k 10k ns RAS Pulse Width (Fast Page Mode Only) tRASP 70 100k 80 100k 100 100k ns RAS Hold Time tRSH 20 — 25 — 25 — ns CAS Hold Time tCSH 70 — 80 — 100 — ns CAS Pulse Width tCAS 20 10k 25 10k 25 10k ns RAS to CAS Delay Time tRCD 20 50 20 55 20 75 ns 13 RAS to Column Address Delay Time tRAD 15 35 15 40 20 50 ns 13 Column Address to RAS Lead Time tRAL 35 — 40 — 55 — ns CAS to RAS Precharge Time tCRP 10 — 10 — 10 — ns CAS Precharge Time tCPN 10 — 10 — 10 — ns CAS Precharge Time (Fast Page Mode) tCP 10 — 10 — 10 — ns Row Address Set-up Time tASR 0 — 0 — 0 — ns Row Address Hold Time tRAH 10 — 10 — 10 — ns Column Address Set-up Time tASC 0 — 0 — 0 — ns Column Address Hold Time tCAH 15 — 15 — 15 — ns Column Address Hold Time referenced to RAS tAR 55 — 55 — 70 — ns Read Command Set-up Time tRCS 0 — 0 — 0 — ns Read Command Hold Time tRCH 0 — 0 — 0 — ns 10 10 Read Command Hold Time referenced to RAS tRRH 0 — 0 — 0 — ns Write Command Hold Time tWCH 15 — 15 — 15 — ns Write Command Hold Time referenced to RAS tWCR 55 — 55 — 70 — ns Write Command Pulse Width tWP 15 — 15 — 15 — ns Write Command to RAS Lead Time tRWL 20 — 20 — 25 — ns Write Command to CAS Lead Time tCWL 20 — 20 — 25 — ns 6/33 ¡ Semiconductor MSM514252A AC Characteristics (2/3) Parameter (VCC = 5 V ±10%, Ta = 0°C to 70°C) Note 4, 5, 6 Symbol -70 -80 -10 Min. Max. Min. Max. Min. Max. Unit Note Data Set-up Time tDS 0 — 0 — 0 — ns 11 Data Hold Time tDH 15 — 15 — 15 — ns 11 Data Hold Time referenced to RAS tDHR 55 — 55 — 70 — ns Write Command Set-up Time tWCS 0 — 0 — 0 — ns 12 RAS to WE Delay Time tRWD 100 — 100 — 130 — ns 12 Column Address to WE Delay Time tAWD 65 — 65 — 80 — ns 12 CAS to WE Delay Time tCWD 45 — 45 — 55 — ns 12 Data to CAS Delay Time tDZC 0 — 0 — 0 — ns Data to OE Delay Time tDZO 0 — 0 — 0 — ns Access Time from OE tOEA — 20 — 20 — 25 ns 7 Output Buffer Turn-off Delay from OE tOEZ 0 10 0 10 0 20 ns 9 OE to Data Delay Time tOED 10 — 10 — 20 — ns OE Command Hold Time tOEH 10 — 10 — 20 — ns RAS Hold Time referenced to OE tROH 15 — 15 — 15 — ns CAS Set-up Time for CAS before RAS Cycle tCSR 10 — 10 — 10 — ns CAS Hold Time for CAS before RAS Cycle tCHR 10 — 10 — 10 — ns RAS Precharge to CAS Active Time tRPC 0 — 0 — 0 — ns Refresh Period tREF — 8 — 8 — 8 ms WB Set-up Time tWSR 0 — 0 — 0 — ns WB Hold Time tRWH 15 — 15 — 15 — ns Write Per Bit Mask Data Set-up Time tMS 0 — 0 — 0 — ns Write Per Bit Mask Data Hold Time tMH 15 — 15 — 15 — ns DT High Set-up Time tTHS 0 — 0 — 0 — ns DT High Hold Time tTHH 15 — 15 — 15 — ns DT Low Set-up Time tTLS 0 — 0 — 0 — ns DT Low Hold Time tTLH 15 10k 15 10k 15 10k ns tRTH 60 10k 65 10k 80 10k ns tATH 25 — 30 — 30 — ns tCTH 20 — 25 — 25 — ns SE Set-up Time referenced to RAS tESR 0 — 0 — 0 — ns SE Hold Time referenced to RAS tREH 15 — 15 — 15 — ns DT to RAS Precharge Time tTRP 60 — 60 — 70 — ns DT Low Hold Time referenced to RAS (Real Time Read Transfer) DT Low Hold Time referenced to Column Address (Real Time Read Transfer) DT Low Hold Time referenced to CAS (Real Time Read Transfer) DT Precharge Time tTP 20 — 20 — 30 — ns RAS to First SC Delay Time (Read Transfer) tRSD 70 — 80 — 100 — ns Column Address to First SC Delay Time (Read Transfer) tASD 45 — 45 — 50 — ns CAS to First SC Delay Time (Read Transfer) tCSD 20 — 25 — 25 — ns Last SC to DT Lead Time (Real Time Read Transfer) tTSL 5 — 5 — 5 — ns 7/33 ¡ Semiconductor MSM514252A AC Characteristics (3/3) Parameter (VCC = 5 V ±10%, Ta = 0°C to 70°C) Note 4, 5, 6 Symbol -70 -80 -10 Min. Max. Min. Max. Min. Max. Unit Note DT to First SC Delay Time (Read Transfer) tTSD 15 — 15 — 15 — ns Last SC to RAS Set-up Time (Serial Input) tSRS 25 — 25 — 30 — ns RAS to First SC Delay Time (Serial Input) tSRD 20 — 20 — 25 — ns RAS to Serial Input Delay Time tSDD 40 — 40 — 50 — ns tSDZ 10 40 10 40 10 50 ns tSCC 30 — 30 — 30 — ns SC Pulse Width (SC High Time) tSC 10 — 10 — 10 — ns SC Precharge Time (SC Low Time) tSCP 10 — 10 — 10 — ns Access Time from SC tSCA — 25 — 25 — 25 ns Serial Output Hold Time from SC tSOH 5 — 5 — 5 — ns Serial Output Buffer Turn-off Delay from RAS (Pseudo Write Transfer) SC Cycle Time Serial Input Set-up Time tSDS 0 — 0 — 0 — ns Serial Input Hold Time tSDH 15 — 15 — 15 — ns Access Time from SE tSEA — 25 — 25 — 25 ns SE Pulse Width tSE 25 — 25 — 25 — ns SE Precharge Time tSEP 25 — 25 — 25 — ns Serial Output Buffer Turn-off Delay from SE tSEZ 0 20 0 20 0 20 ns Serial Input to SE Delay Time tSZE 0 — 0 — 0 — ns Serial Input to First SC Delay Time tSZS 0 — 0 — 0 — ns Serial Write Enable Set-up Time tSWS 5 — 5 — 5 — ns Serial Write Enable Hold Time tSWH 15 — 15 — 15 — ns Serial Write Disable Set-up Time tSWIS 5 — 5 — 5 — ns Serial Write Disable Hold Time tSWIH 15 — 15 — 15 — ns 9 8 8 9 8/33 ¡ Semiconductor Notes: MSM514252A 1. These parameters depend on output loading. Specified values are obtained with the output open. 2. These parameters are masured at minimum cycle test. 3. ICC2 (Max.) are mesured under the condition of TTL input level. 4. VIH (Min.) and VIL (Max.) are reference levels for measuring timing of input signals. Also, transition times are measured between VIH and VIL. 5. An initial pause of 200 ms is required after power-up followed by any 8 RAS cycles (DT/OE “high”) and any 8 SC cycles before proper divice operation is achieved. In the case of using an internal refresh counter, a minimum of 8 CAS before RAS initialization cycles in stead of 8 RAS cycles are required. 6. AC measurements assume tT = 5 ns. 7. RAM port outputs are mesured with a load equivalent to 1 TTL load and 100 pF. Output reference levels are VOH/VOL = 2.4 V/0.8 V. 8. SAM port outputs are measured with a load equivalent to 1 TTL load and 30 pF. Output reference levels are VOH/VOL = 2.0 V/0.8 V. 9. tOFF (Max.), tOEZ (Max.), tSDZ (Max.) and tSEZ (Max.) difine the time at which the outputs achieve the open circuit condition and are not reference to output voltage levels. 10. Either tRCH or tRRH must be satisfied for a read cycle. 11. These parameters are referenced to CAS leading edge of early write cycles and to WB/WE leading edge in OE controlled write cycles and read modify write cycles. 12. tWCS, tRWD, tCWD and tAWD are not restrictive operating parameters. They are included in the data sheet as electrical characteristics only. If tWCS ≥ tWCS (Min.), the cycle is an early write cycle, and the data out pin will remain open circuit (high impedance) throughout the entire cycle : If tRWD ≥ tRWD (Min.), tCWD ≥ tCWD (Min.) and tAWD ≥ tAWD (Min.) the cycle is a read-write cycle and the data out will contain data read from the selected cell : If neither of the above sets of conditions is satisfied, the condition of the data out (at access time) is indterminate. 13. Operation within the tRCD (Max.) limit ensures that tRAC (Max.) can be met. tRCD (Max.) is specified as a reference point only : If tRCD is greater than the specified tRCD (Max.) limit, then access time is controlled by tCAC. 14. Operation within the tRAD (Max.) limit ensures that tRAC (Max.) can be met. tRAD (Max.) is specified as a reference point only : If tRAD is greater than the specified tRAD (Max.) limit, then access time is controlled by tAA. 15. Input levels at the AC parameter measurement are 3.0 V/0 V. 16. Stresses greater than those listed under “Absolute Maximum Ratings” may cause permenent damege to the device. 17. All voltages are referenced to VSS. 9/33 ¡ Semiconductor MSM514252A ,, , TIMING WAVEFORM Read Cycle tRC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP CAS tRSH VIH – VIL – tCPN tCAS VIH – VIL – tASR A0 - A8 tRCD tRAD tRAH Row Address tRAL tCAH tASC Column Address tRCH tRCS WB/WE VIH – VIL – tTHS DT/OE tRRH tROH tTHH VIH – VIL – tOEA tDZO IN VIH – tAA W1/IO1 - W4/IO4 OUT tCAC VIL – tRAC VOH – VOL – Open tOFF tOEZ Valid Data-out "H" or "L" 10/33 ¡ Semiconductor MSM514252A ,, , , Write Cycle (Early Write) tRC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP tRCD tRSH tRAD tRAH tASR A0 - A8 VIH – VIL – tRAL tASC Row Address tWSR WB/WE VIH – VIL – tRWH tCAH Column Address tWCS tWCH tWP *1 tWCR DT/OE IN tTHS tTHH tMS tMH tCWL tRWL VIH – VIL – VIH – VIL – tDS tDH WM1 Data Valid Data-in tDHR W1/IO1 - W4/IO4 OUT tCPN tCAS VIH – CAS VIL – VOH – Open VOL – "H" or "L" *1 WB/WE W1/IO1 - W4/IO4 Cycle 0 WM1 data Write per Bit 1 Don't Care Normal Write WM1 data: 0: Write Disable 1: Write Enable 11/33 ¡ Semiconductor MSM514252A ,, , , , Write Cycle (OE Controlled Write) tRC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP CAS tRCD tCAS VIH – VIL – tRAD tASR A0 - A8 VIH – VIL – tCPN tRSH tRAH Row Address tRAL tCAH tASC Column Address tCWL tWSR VIH – WB/WE VIL – tRWH tRWL tWP *1 tWCR tTHS DT/OE VIL – tMS IN tOEH VIH – VIH – VIL – tDH Valid Data-in WM1 Data tDHR W1/IO1 - W4/IO4 OUT tDS tMH VOH – Open VOL – "H" or "L" Cycle *1 WB/WE W1/IO1 - W4/IO4 0 WM1 data Write per Bit Don't Care Normal Write 1 WM1 data: 0: Write Disable 1: Write Enable 12/33 ¡ Semiconductor MSM514252A , ,, , , Read Modify Write Cycle tRWC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP CAS tRCD tRSH tCPN tCAS VIH – VIL – tRAD tASR A0 - A8 VIH – VIL – tASC tRAH Row Address tCAH Column Address tCWL tWSR WB/WE VIH – tRWH tRCS tCWD *1 VIL – tRWL tWP tAWD tRWD tTHH tTHS DT/OE tOEH VIH – VIL – tDS tDZC tMS IN VIH – VIL – tMH tDZO WM1 Data W1/IO1 - W4/IO4 OUT tOED Valid Data-in tOEA tAA tRAC VOH – tCAC tOEZ Valid Data-out Open VOL – tDH "H" or "L" *1 WB/WE W1/IO1 - W4/IO4 Cycle 0 WM1 data Write per Bit 1 Don't Care Normal Write WM1 data: 0: Write Disable 1: Write Enable 13/33 ¡ Semiconductor MSM514252A , , , Fast Page Mode Read Cycle tRASP RAS tAR VIH – VIL – tRP tPC tRSH tCRP CAS VIH – VIL – tASR A0 - A8 VIH – VIL – tRCD tCP tRAD tCSH tRAH tASC Row Address tCP tCAS tASC tCAH Column Address 1 tCAH Column Address N tRCH tRCH tRCS tRCS tRRH VIH – VIL – tTHS tTHH VIH – VIL – tDZO tCPA VIH – IN VIL – tOEA tCAC W1/IO1 - W4/IO4 OUT tASC Column Address 2 tRCS DT/OE tCPN tRAL tCAH tRCH WB/WE tCAS tCAS tRAC VOH – VOL – Open tAA tCPA tOEA tOFF tOEZ Data-out 1 tCAC tAA tOEA tOFF tOEZ Data-out 2 tCAC tAA tOFF tOEZ Data-out N "H" or "L" 14/33 ¡ Semiconductor MSM514252A , , , , Fast Page Mode Write Cycle (Early Write) tRASP RAS tAR VIH – VIL – tRP tPC tRSH tCRP VIH – CAS VIL – tASR A0 - A8 VIH – VIL – tCP tRCD tCAS tRAD tCSH tRAH tASC Row Address tCP tCAH tCAH tASC Column Address 1 Column Address 2 tWCR tWSR WB/WE tRWH tWCS VIH – tWCH DT/OE tWCH tWP tWP tCWL tCWL tRWL VIH – VIL – tMH VIH – VIL – W1/IO1 - W4/IO4 OUT Column Address N tTHH tMS IN tCAH tWCS tWCL tTHS tCPN tRAL tASC tWCH tWCS tWP VIL – tCAS tCAS tDS WM1 Data tDH Data-in 1 tDH tDS tDH tDS Data-in 2 Data-in N tDHR VOH – Open VOL – "H" or "L" *1 WB/WE W1/IO1 - W4/IO4 Cycle 0 WM1 data Write per Bit 1 Don't Care Normal Write WM1 data: 0: Write Disable 1: Write Enable 15/33 ¡ Semiconductor MSM514252A ,, , , , Fast Page Mode Read Modify Write Cycle tRASP tRP tAR RAS VIH – VIL – tCSH tPRWC CAS VIH – VIL – tASR VIH – A0 - A8 VIL – VIH tWSR – WB/WE V – IL tTHS VIH – DT/OE V – IL tCAS tRAH Row Address OUT tCAS tASC tCAH tCAH tCWL Column Address 2 tRWL Column Address N tWP tWP tCWD *1 tCWL tASC tCAH tCWL Column Address 1 tWP tCWD tCWD tRWD tTHH tRFH tDZO tDZC WM1 Data tDS tOED tDH tCAC tAA tRAC tDZO tOED tOEZ tDS tCAC tAA Dataout 1 tDZC Datain 2 tOEA tDS tDZO tDH tDZC Datain 1 tOEA W1/IO1 - W4/IO4 VOH – tCAS tRWH tMH VIH – VIL – tCP tASC tMS IN tRSH tCP tRCD tOED Datain N tOEA tOEZ tCAC tAA Dataout 2 tDH tOEZ Dataout N VOL – "H" or "L" *1 WB/WE W1/IO1 - W4/IO4 Cycle 0 WM1 data Write per Bit 1 Don't Care Normal Write WM1 data: 0: Write Disable 1: Write Enable 16/33 ¡ Semiconductor MSM514252A ,, , RAS-Only Refresh Cycle tRC tRAS RAS tRP VIH – VIL – tRPC tCRP CAS VIH – VIL – tASR A0 - A8 WB/WE VIH – VIL – tRAH Row Address VIH – VIL – tTHS DT/OE tCRP tTHH VIH – VIL – W1/IO1 VOH – - W4/IO4 VOL – Open "H" or "L" 17/33 ¡ Semiconductor MSM514252A ,,, , , CAS before RAS Refresh Cycle tRC tRP RAS tRP tRAS VIH – VIL – tRPC tCSR tCPN tCHR VIH – CAS VIL – WB/WE VIH – VIL – DT/OE VIH – VIL – tOFF W1/IO1 VOH – - W4/IO4 VOL – Open Note: A0 - A8 = Don't Care ("H" or "L") "H" or "L" 18/33 ¡ Semiconductor MSM514252A ,, , Hidden Refresh Cycle tRC RAS tRAS tAR VIH – VIL – tCRP CAS tRP tRAS tRSH tRCD tRP tCHR tCPN VIH – VIL – tRAL tRAD tASR A0 - A8 tRC VIH – VIL – tRAH tASC tCAH Column Address Row Address tWSR tRCS WB/WE tRWH VIH – VIL – tTHS DT/OE tRRH tTHH tROH VIH – VIL – tOEA tOEZ tOFF VOH – W1/IO1 - W4/IO4 VOL – tAA tOFF tCAC tOEZ Valid Data-out "H" or "L" 19/33 ¡ Semiconductor MSM514252A , , Read Transfer Cycle (Previous Transfer is Write Transfer Cycle) tRC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP CAS tRCD tRSH tCAS VIH – VIL – tRAD tASR A0 - A8 VIH – tRAH Row Address VIL – tRAL tCAH tASC SAM Start Address A0 - A8: TAP tWSR WB/WE tCPN tRWH VIH – VIL – tTRP tTLS tTLH tTP VIH – DT/OE VIL – tASD tCSD tOFF tRSD W1/IO1 VOH – - W4/IO4 VOL – tTSD tSRS SC VIH – VIL – VIH – VIL – SIO1 - SIO4 tSCC tSC Inhibit Rising Transient tSDH tSZS Valid Data-in tSCA OUT tSCP tSC tSDS IN tSCP VOH – tSOH Valid Data-out VOL – Note: SE = VIL "H" or "L" 20/33 ¡ Semiconductor MSM514252A , ,, , , Real Time Read Transfer Cycle tRC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP CAS tRCD VIH – VIL – tRAD tRAH tRAL tASC Row Address tCAH SAM Start Address A0 - A8: TAP tWSR WB/WE tCPN tCAS VIH – VIL – tASR A0 - A8 tRSH tRWH tATH VIH – VIL – tCTH tTLS DT/OE tTRP tRTH tTP VIH – VIL – tOFF W1/IO1 VOH – - W4/IO4 VOL – tSCC tSC SC VIH – VIL – IN VIH – VIL – SIO1 - SIO4 tTSL tSCP Open tSCA tTSD tSCA tSOH OUT VOH – VOL – Valid Data-out tSOH Valid Data-out Valid Data-out Valid Data-out Valid Data-out Previous Row Data New Row Data Note: SE = VIL "H" or "L" 21/33 ¡ Semiconductor MSM514252A , , Pseudo Write Transfer Cycle tRC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP CAS WB/WE VIH – VIL – tCPN tCAS VIH – VIL – tRAD tRAH tASR A0 - A8 tRSH tRCD Row Address tASC tRAL tCAH SAM Start Address A0 - A7: TAP tWSR tRWH tTLS tTLH VIH – VIL – VIH – DT/OE VIL – tOFF W1/IO1 VOH – - W4/IO4 VOL – Open tSRD tSRS SC tSCP VIH – VIL – SIO1 - SIO4 OUT VOH – VOL – tSCP Inhibit Rising Transient tESR VIH – VIL – tSC tSC tSWS tREH VIH – SE VIL – IN tSCC tSDD tSDZ tSEZ tSDS Valid Data-in tSCA Valid Data-out Valid Data-out tSDH Open tSOH Serial Output Data Serial Input Data "H" or "L" 22/33 ¡ Semiconductor MSM514252A , , Write Transfer Cycle tRC tRAS RAS tRP tAR VIH – VIL – tCSH tCRP CAS tRCD tRSH tCAS VIH – VIL – tRAL tRAD tASR A0 - A8 WB/WE DT/OE tCPN VIH – tRAH Row Address VIL – tASC tCAH SAM Start Address A0 - A8: TAP tWSR tRWH tTLS tTLH VIH – VIL – VIH – VIL – tOFF VOH – W1/IO1 - W4/IO4 VOL – Open tSRD tSRS SC VIH – VIL – tSCP tSCP Inhibit Rising Transient tSWS tREH VIH – VIL – tSDS IN tSC tSC tESR SE tSCC VIH – VIL – tSDH tSDS tSDH Valid Data-in Valid Data-in Valid Data-in SIO1 - SIO4 OUT VOH – Open VOL – Previous Row Data New Row Data "H" or "L" 23/33 ,,, ,, , , ¡ Semiconductor MSM514252A Serial Read Cycle (SE = VIL) RAS VIH – VIL – tTHS DT/OE tTHH VIH – VIL – tSCC tSCC tSC SC tSCC tSC tSCC tSC tSCC tSC tSC VIH – VIL – tSCP tSCA tSCP tSOH VOH – SIO1 - SIO4 VOL – tSCA tSCP tSOH Valid Data-out tSCA tSCP tSCA tSOH Valid Data-out tSCP tSOH Valid Data-out tSCA tSCP tSOH Valid Data-out Valid Data-out Valid Data-out Note: SE = VIL "H" or "L" Serial Read Cycle (SE Controlled Outputs) RAS VIH – VIL – tTHS DT/OE VIH – VIL – tSCC tSCC tSC SC tSCC tSC tSCC tSC tSCC tSC tSC VIH – VIL – tSCP SE tTHH tSCP tSCP tSEP tSCP tSCP tSCP VIH – VIL – tSZE IN VIH – VIL – SIO1 - SIO4 tSOH OUT VOH – VOL – tSEA tSCA Valid Data-out tSCA tSEZ Valid Data-out Open tSCA tSOH Valid Data-out tSCA tSOH Valid Data-out Valid Data-out "H" or "L" 24/33 ,, , ,, , , ¡ Semiconductor MSM514252A Serial Write Cycle (SE = VIL) RAS VIH – VIL – tTHS tTHH VIH – DT/OE VIL – tSCC tSCC tSC SC VIH – VIL – tSDH tSDS tSCC tSC tSDH tSCP SIO1 VIH – - SIO4 VIL – tSCC tSC tSCC tSC tSDH tSC tSDH tSDH tSCP tSCP tSCP tSCP tSDS tSDS tSDS tSDS Valid Data-in Valid Data-in Valid Data-in Valid Data-in tSCP Valid Data-in Valid Data-in Note: SE = VIL "H" or "L" Serial Write Cycle (SE Controlled Inputs) RAS VIH – VIL – tTHS DT/OE VIH – VIL – tSCC tSC SC VIH – VIL – tSCP VIH – VIL – VIH – VIL – Valid Data-in tSC tSCP tSWIH tSEP tSE tSDH tSCC tSC tSWH tSDS IN tSCC tSCP tSWS SE tTHH tSWIS tSDS tSCC tSCC tSC tSCP tSC tSCP tSCP tSWIH tSWS tSWH tSE tSDH Valid Data-in tSEP tSWS tSWH tSWIS tSDS tSE tSDH Valid Data-in SIO1 - SIO4 OUT VOH – VOL – Open "H" or "L" 25/33 ¡ Semiconductor MSM514252A PIN FUNCTION Address Input: A0 - A8 The 18 address bits decode an 8-bit location out of the 262,144 locations in the MSM514252A memory array. The address bits are multiplexed to 9 address input pins (A0 - A8) as standard DRAM. Nine row address bits are latched at the falling edge of RAS. The following nine column address bits are latched at the falling edge of CAS. Row Addres Strobe: RAS RAS is a basic RAM control input signal. The RAM port is in standby mode when the RAS level is "high". As the standard DRAM’s RAS signal function, RAS is the control input that latches the row address bits and a random access cycle begins at the falling edge of RAS. In addition to the conventional RAM signal functions, the level of the input signals, CAS, DT/ OE, WB/WE, and SE, at the falling edge of RAS, determines the MSM514252A operation modes. Column Address Strobe: CAS As the standard DRAM’s CAS signal function, CAS is the control input signal that latches the column address input and acts as an RAM port output enable signal. Data Transfer/Output Enable: DT/OE DT/OE is also a control input signal having multiple functions. As the standard DRAM’s OE signal function, DT/OE is used as an output enable control when DT/OE is "high" at the falling edge of RAS. In addition to the conventional OE signal function, a data transfer operation is started between the RAM port and the SAM port when the DT/OE is "low" at the falling edge of RAS. Write per Bit/Write Enable: WB/WE WB/WE is a control input signal having multiple functions. As the standard DRAM’s WE signal function, it is used to write data into the memory array on the RAM port when WB/WE is "high" at the falling edge of RAS. In addition to the conventional WE signal function, the WB/WE determines the write-per-bit function when WB/WE is "low" at the falling edge of RAS, during RAM port operations. The WB/WE also determines the direction of data transfer between the RAM and SAM. When WB/ WE is "high" at the falling edge of RAS, the data is transferred from RAM to SAM (read transfer). When WB/WE is "low" at the falling edge of RAS, the data is transferred from SAM to RAM (write transfer). 26/33 ¡ Semiconductor MSM514252A Write Mask Data/Data Input and Output: W1/IO1 - W4/IO4 W1/IO1 - W4/IO4 have the functions of both Input/Output and a control input signal. As the standard DRAM’s I/O pins, input data on the W1/IO1 - W4/IO4 are written into the RAM port during the write cycle. The input data is latched at the falling edge of either CAS or WB/WE, whichever occurs later. The RAM data out buffers, which will output read data from the W1/ IO1-W4/IO4 pins, become low impedance state after the specified access times from RAS, CAS, DT/OE and column address are satisfied and the output data will remain valid as long as CAS and DT/OE are kept "low". The outputs will return to the high-impedance state at the rising edge of either CAS or DT/OE, whichever occurs earlier. In addition to the conventional I/O functions, the W1/IO1 - W4/IO4 have the function to set the mask data, which select mask input pins out of four inputs pins, W1/IO1 - W4/IO4, at the falling edge of RAS. Data is written in to the DRAM on data lines where the write-mask data is a logic "1". Writing is inhibited on data lines where the write-mask data is a logic "0". The write-mask data is valid for only one cycle. Serial Clock: SC SC is a main serial cycle control input signal. All operations of the SAM port are synchronized with the serial clock SC. Data is shifted in or out of the SAM registers at the rising edge of SC. In a serial read, the output data becomes valid on the SIO pins after the maximum specified serial access time tSCA from the rising edge of SC. The serial clock SC also increments the 9 bits serial pointer which is used to select the SAM address. The pointer address is incremented in a wrap-around mode to select sequential locations after the setting location which is determined by the column address in the read transfer cycle. When the pointer reaches the most significant address location (decimal 511), the next SC clock will place it at the least significant address location (decimal 0). The serial clock SC must be held data constant VIH or VIL level during read/pseudo write/write transfer operations and should not be clocked while the SAM port is in the standby mode to prevent the SAM pointer from being incremented. Serial Enable: SE The SE is a serial access enable control and serial read/write control input signal. In a serial read cycle, SE is used as an output control. In a serial write cycle, SE is used as a write enable control. When SE is "high", serial access is disable, however, the serial address pointer location is still incremented when SC is clocked even when SE is "high". Serial Input/Output: SIO1 - SIO4 Serial input/output mode is determined by the most recent read, write or pseudo write transfer cycle. When a read transfer cycle is performed, the SAM port is in the output mode. When a write or pseudo write transfer cycle is performed, the SAM port is switched from output mode to input mode. 27/33 ¡ Semiconductor MSM514252A RAM PORT OPERATION Fast Page Mode Cycle Fast page mode allows data to be transferred into or out of multiple column locations of the same row by performing multiple CAS cycle during a single active RAS cycle. During a fast page cycle, the RAS signal may be maintained activity for a period up to 100µ seconds. For the initial fast page mode access, the output data is valid after the specified access times from RAS, CAS, column address and DT/OE. For all subsequent fast page mode read operations, the output data is valid after the specified access times from CAS, column address and DT/OE. When the write-per-bit function is enabled, the mask data latched at the falling edge of RAS is maintained throughout the fast page mode write or Read-Modify-Write cycle. RAS-Only Refresh The data in the DRAM requires periodic refreshing to prevent data loss. Refreshing is accomplished by performing a memory cycle at each of the 512 rows in the DRAM array within the specified 8 ms refresh period. Although any normal memory cycle will perform the refresh operation, this function is most easily accomplished with "RAS-Only" cycle. CAS before RAS Refresh The MSM514252A also offers an internal-refresh function. When CAS is held "low" for a specified period (tCSR) before RAS goes "low", an internal refresh address counter and on-chip refresh control clock generators are enabled and an internal refresh operation takes place. When the refresh operation is completed, the internal refresh address counter is automatically incremented in preparation for the next CAS-before-RAS cycle. For successive CAS-before-RAS refresh cycle, CAS can remain "low" while cycling RAS. Hidden Refresh A hidden refresh is a CAS-before-RAS refresh performed by holding CAS "low" from a previous read cycle. This allows for the out put data from the previous memory cycle to remain valid while performing a refresh. The internal refresh address counter provides the address and the refresh is accomplished by cycling RAS after the specified RAS-precharge period. Write-per-Bit Function The Write-Per-Bit selectively controls the internal write-enable circuits of the RAM port. WritePer-Bit is enabled when WB/WE is held "low" at the falling edge of RAS in a random write operation. Also, at the falling edge of RAS, the mask data on the Wi/IOi pins are latched into a write mask register. The write mask data must be presented at the Wi/IOi pins at every falling edge of RAS. A "0" on any of the Wi/IOi pins will disable the corresponding write circuits and new data will not be written into the RAM. A "1" on any of the Wi/IOi pins will enable the corresponding write circuits and new data will be written into the RAM. 28/33 ¡ Semiconductor MSM514252A DATA TRANSFER OPERATION The MSM514252A features an internal data transfer capability between RAM and the SAM. During a transfer cycle, 512 words by 4 bits of data can be loaded from RAM to SAM (Read Transfer) or from SAM to RAM (Write Transfer). The MSM514252A supports three types of transfer operations: Read transfer, Write Transfer and pseudo write transfer. Data transfer operations between RAM and SAM are invoked by holding the DT/OE signal "low" at the falling edge of RAS, the type of data transfer operation is determined by the state of CAS, WB/WE and SE latched at the falling edge of RAS. During data transfer operations, the SAM port is switched from input to output mode (Read transfer) or output to input mode (Write transfer/pseudo write transfer). During a data transfer cycle, the row A0-A8 select one of the 512 rows of the memory array to or from which data will be transferred and the column address A0-A8 select one of the tap locations in the serial register. The selected tap location is the start position in the SAM port from which the first serial data will be read out during the subsequent serial read cycle or the start position in the SAM port into which the first serial data will be written during the subsequent serial write cycle. Read Transfer Cycle A read transfer consists of loading a selected row of data from the RAM array into the SAM register. A read transfer is invoked by holding CAS "high", DT/OE "low" and WB/WE "high" at the falling edge of RAS. The row address selected at the falling edge of RAS determines the RAM row tho by transferred into the SAM. The transfer cycle is completed at the rising edge of DT/OE. When the transfer is completed, the SAM port is set into the output mode. In a read/real time read transfer cycle, the transfer of a new row of data is completed at the rising edge of DT/OE and this data becomes valid on the SIO lines after the specified access time tSCA from the rising edge of the subsequent serial clock (SC) cycle. The start address of the serial pointer of the SAM is determined by the column address selected at the falling edge of CAS. In a read transfer cycle preceded by a write transfer cycle, the SC clock must be held at a constant VIL or VIH, after the SC high time has been satisfied. A rising edge of the SC clock must not occur until after the specified delay tTSD from the rising edge of DT/OE. In a real time read transfer cycle (which is preceded by another read transfer cycle), the previous row data appears on the SIO lines until the DT/OE signal goes "high" and the serial access time tSCA for the following serial clock is satisfied. This feature allows for the first bit of the new row of data to appear on the serial output as soon as the last bit of the previous row has been strobed without any timing loss. To make this continuous data flow possible , the rising edge of DT/OE must be synchronized with RAS, CAS and the subsequent rising edge of SC (tRTH, tCTH, and tTSL/tTSD must be satisfied). The timing restriction tTSL/tTSD are 5 ns min./10 ns min.. 29/33 ¡ Semiconductor MSM514252A Write Transfer Cycle A write transfer cycle transfers the contents of the SAM register into a selected row of the RAM array. If the SAM data to be transferred must first be loaded through the SAM port, a pseudo write transfer operation must precede the write transfer cycles. However, if the SAM data to be transferred into the RAM was previously loaded into the SAM via a read transfer, the SAM to RAM transfer can be executed simply by performing a write transfer cycle. A write transfer is invoked by holding CAS "low", WB/WE "low" and SE "low" at the falling edge of RAS. The row address selected at the falling edge of RAS determines the RAM row address into which the data will be transferred. The column address selected at the falling edge of CAS determines the start address of the serial pointer of the SAM. After the write transfer is completed, the SIO lines are set in the input mode so that serial data synchronized with the SC clock can be loaded. When consecutive write transfer operations are performed, new data must not be written into the serial register until the RAS cycle of the preceding write transfer is completed. Consequently, the SC clock must be held at a constant VIL or VIH during the RAS cycle. A rising edge of the SC clock is only allowed after the specified delay tSRD from the rising edge of RAS, at which time a new row of data can be written in the serial register. Pseudo Write Transfer Cycle A pseudo write transfer cycle must be performed before loading data into the serial register after a read transfer operation has been executed. The only purpose of a pseudo write transfer is to change the SAM port mode from output mode to input mode (A data transfer from SAM to RAM does not occur). After the serial register is loaded with new data, a write transfer cycle must be performed to transfer the data from SAM to RAM. A pseudo write transfer is invoked by holding CAS "high" DT/OE "low", WB/WE "low" and SE "high" at the falling edge of RAS. The timing conditions are the same as the one for the write transfer cycle except for the state of SE at the falling edge of RAS. Transfer Operation Without CAS During all transfer cycles, the CAS input clock must be cycled, so that the column addresses are latched at the falling edge of CAS, to set the SAM tap location. If CAS was maintained at a constant "high" level during a transfer cycle, the SAM pointer location would be undefined. Therefore a transfer cycle with CAS held "high" is not allowed. Normal Read Transfer Cycle After Normal Read Transfer Cycle Another read transfer may be performed following the read transfer provided that a minimum delay of 30 ns from the rising edge of the first clock SC is satisfied. 30/33 ¡ Semiconductor MSM514252A POWER-UP Power must be applied to the RAS and DT/OE input signals to pull them "high" before or at the same time as the VCC supply is turned on. After power-up, a pause of 200µ seconds (minimum) is required with RAS and DT/OE held "high". After the pause, a minimum of 8 RAS and 8 SC dummy cycles must be performed to stabilize the internal circuitry, before valid read, write or transfer operations can begin. During the initialization period, the DT/OE signal must be held "high". If the internal refresh counter is used, a minimum 8 CAS-before-RAS initialization cycles are required instead of 8 RAS cycles. Initial State After Power-up When power is achieved with RAS, CAS, DT/OE and WB/WE held "high" the internal state of the MSM514252A is automatically set as follows. SAM port ------------------- Æ Input mode Write mask register ------ Æ Write mode TAP pointer ---------------- Æ Invalid However, the initial state can not be guaranteed for various power-up conditions and input signal levels. Therefore, it is recommended that the initial state be set after the initialization of the device is performed (200µ seconds pause followed by a minimum of 8 RAS cycles and 8 SC cycles) and before valid operations begin. 31/33 ¡ Semiconductor MSM514252A PACKAGE DIMENSIONS (Unit : mm) ZIP28-P-400-1.27 Mirror finish Package material Lead frame material Pin treatment Solder plate thickness Package weight (g) Epoxy resin 42 alloy Solder plating 5 mm or more 1.85 TYP. 32/33 ¡ Semiconductor MSM514252A (Unit : mm) SOJ28-P-400-1.27 Mirror finish Package material Lead frame material Pin treatment Solder plate thickness Package weight (g) Epoxy resin 42 alloy Solder plating 5 mm or more 1.30 TYP. Notes for Mounting the Surface Mount Type Package The SOP, QFP, TSOP, SOJ, QFJ (PLCC), SHP and BGA are surface mount type packages, which are very susceptible to heat in reflow mounting and humidity absorbed in storage. Therefore, before you perform reflow mounting, contact Oki’s responsible sales person for the product name, package name, pin number, package code and desired mounting conditions (reflow method, temperature and times). 33/33