IS62C256 32K x 8 LOW POWER CMOS STATIC RAM FEATURES ISSI ® DESCRIPTION The ISSI IS62C256 is a low power, 32,768 word by 8-bit CMOS static RAM. It is fabricated using ISSI's high- • Access time: 45, 70 ns • Low active power: 200 mW (typical) • Low standby power — 250 µW (typical) CMOS standby — 28 mW (typical) TTL standby • Fully static operation: no clock or refresh required • TTL compatible inputs and outputs • Single 5V power supply performance, low power CMOS technology. When CS is HIGH (deselected), the device assumes a standby mode at which the power dissipation can be reduced down to 250 µW (typical) at CMOS input levels. Easy memory expansion is provided by using an active LOW Chip Select (CS) input and an active LOW Output Enable (OE) input. The active LOW Write Enable (WE) controls both writing and reading of the memory. The IS62C256 is pin compatible with other 32K x 8 SRAMs in plastic SOP or TSOP (Type I) package. FUNCTIONAL BLOCK DIAGRAM A0-A14 DECODER 32K X 8 MEMORY ARRAY I/O DATA CIRCUIT COLUMN I/O VCC GND I/O0-I/O7 CS OE CONTROL CIRCUIT WE ISSI reserves the right to make changes to its products at any time without notice in order to improve design and supply the best possible product. We assume no responsibility for any errors which may appear in this publication. © Copyright 1999, Integrated Silicon Solution, Inc. Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99 1 ISSI IS62C256 PIN CONFIGURATION PIN CONFIGURATION 28-Pin SOP 28-Pin TSOP A14 1 28 VCC A12 2 27 WE A7 3 26 A13 A6 4 25 A8 A5 5 24 A9 A4 6 23 A11 A3 7 22 OE A2 8 21 A10 A1 9 20 CS A0 10 19 I/O7 I/O0 11 18 I/O6 I/O1 12 17 I/O5 I/O2 13 16 I/O4 GND 14 15 I/O3 PIN DESCRIPTIONS A0-A14 CS OE WE OE A11 A9 A8 A13 WE VCC A14 A12 A7 A6 A5 A4 A3 Mode Chip Select Input Not Selected (Power-down) Output Disabled Read Write Write Enable Input I/O0-I/O7 Input/Output Vcc Power GND Ground A10 CS I/O7 I/O6 I/O5 I/O4 I/O3 GND I/O2 I/O1 I/O0 A0 A1 A2 TRUTH TABLE Address Inputs Output Enable Input 21 20 19 18 17 16 15 14 13 12 11 10 9 8 22 23 24 25 26 27 28 1 2 3 4 5 6 7 ® WE CS OE I/O Operation Vcc Current X H X High-Z ISB1, ISB2 H H L L L L H L X High-Z DOUT DIN ICC1, ICC2 ICC1, ICC2 ICC1, ICC2 ABSOLUTE MAXIMUM RATINGS(1) Symbol VTERM TBIAS TSTG PT IOUT Parameter Terminal Voltage with Respect to GND Temperature Under Bias Storage Temperature Power Dissipation DC Output Current (LOW) Value –0.5 to +7.0 –55 to +125 –65 to +150 0.5 20 Unit V °C °C W mA Note: 1. Stress greater than those listed under 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. 2 Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99 ISSI IS62C256 ® OPERATING RANGE Range Commercial Industrial Ambient Temperature 0°C to +70°C –40°C to +85°C VCC 5V ± 10% 5V ± 10% DC ELECTRICAL CHARACTERISTICS Symbol VOH VOL VIH VIL ILI ILO Parameter Output HIGH Voltage Output LOW Voltage Input HIGH Voltage Input LOW Voltage(1) Input Leakage Test Conditions VCC = Min., IOH = –1.0 mA VCC = Min., IOL = 2.1 mA Output Leakage GND ≤ VOUT ≤ VCC, Outputs Disabled GND ≤ VIN ≤ VCC Com. Ind. Com. Ind. Min. 2.4 — 2.2 –0.3 –2 –10 –2 –10 Max. — 0.4 VCC + 0.5 0.8 2 10 2 10 Unit V V V V µA µA Note: 1. VIL = –3.0V for pulse width less than 10 ns. POWER SUPPLY CHARACTERISTICS(1) (Over Operating Range) Symbol ICC1 ICC2 ISB1 ISB2 Parameter Vcc Operating Supply Current Vcc Dynamic Operating Supply Current TTL Standby Current (TTL Inputs) CMOS Standby Current (CMOS Inputs) Test Conditions VCC = Max., CS = VIL IOUT = 0 mA, f = 0 VCC = Max., CS = VIL IOUT = 0 mA, f = fMAX VCC = Max., VIN = VIH or VIL CS ≥ VIH, f = 0 VCC = Max., CS ≥ VCC – 0.2V, VIN ≥ VCC – 0.2V, or VIN ≤ 0.2V, f = 0 Com. Ind. Com. Ind. Com. Ind. Com. Ind. -45 ns Min. Max. — 60 — 70 — 70 — 80 — 5 — 10 — — 0.5 1.0 -70 ns Min. Max. — 60 — 70 — 65 — 75 — 5 — 10 — — 0.5 1.0 Unit mA mA mA mA Note: 1. At f = fMAX, address and data inputs are cycling at the maximum frequency, f = 0 means no input lines change. CAPACITANCE(1,2) Symbol CIN COUT Parameter Input Capacitance Output Capacitance Conditions VIN = 0V VOUT = 0V Max. 8 10 Unit pF pF Notes: 1. Tested initially and after any design or process changes that may affect these parameters. 2. Test conditions: TA = 25°C, f = 1 MHz, Vcc = 5.0V. Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99 3 ISSI IS62C256 ® DATA RETENTION CHARACTERISTICS Symbol VDR IDR1 IDR2 Parameter VCC for retention of data Data retention current Data retention current Test Conditions Min. 2.0 — — VDR = 3.0V, TA = 0°C to +25°C VDR = 3.0V, TA = 0°C to +70°C Max. — 200 200 Units V µA µA READ CYCLE SWITCHING CHARACTERISTICS(1) (Over Operating Range) Symbol -45 ns Min. Max. Parameter -70 ns Min. Max. Unit tRC Read Cycle Time 45 — 70 — ns tAA Address Access Time — 45 — 70 ns tOHA Output Hold Time 2 — 2 — ns — 45 — 70 ns — 25 — 35 ns 0 — 0 — ns 0 20 0 25 ns 3 — 3 — ns 0 20 0 25 ns 0 — 0 — ns — 30 — 50 ns tACS tDOE tLZOE (2) tHZOE (2) tLZCS(2) tHZCS(2) tPU (3) tPD (3) CS Access Time OE Access Time OE to Low-Z Output OE to High-Z Output CS to Low-Z Output CS to High-Z Output CS to Power-Up CS to Power-Down Notes: 1. Test conditions assume signal transition times of 5 ns or less, timing reference levels of 1.5V, input pulse levels of 0 to 3.0V and output loading specified in Figure 1. 2. Tested with the load in Figure 2. Transition is measured ±500 mV from steady-state voltage. Not 100% tested. 3. Not 100% tested. AC TEST CONDITIONS Parameter Input Pulse Level Input Rise and Fall Times Input and Output Timing and Reference Levels Output Load Unit 0V to 3.0V 3 ns 1.5V See Figures 1 and 2 AC TEST LOADS 480 Ω 5V OUTPUT OUTPUT 100 pF Including jig and scope Figure 1. 4 480 Ω 5V 255 Ω 5 pF Including jig and scope 255 Ω Figure 2. Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99 ISSI IS62C256 ® AC WAVEFORMS READ CYCLE NO. 1(1,2) t RC ADDRESS t AA t OHA t OHA DOUT DATA VALID PREVIOUS DATA VALID READ1.eps READ CYCLE NO. 2(1,3) t RC ADDRESS t AA t OHA OE t HZOE t DOE t LZOE CS t ACS t HZCS t LZCS DOUT HIGH-Z DATA VALID CS_RD2.eps Notes: 1. WE is HIGH for a Read Cycle. 2. The device is continuously selected. OE, CS = VIL. 3. Address is valid prior to or coincident with CS LOW transitions. Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99 5 ISSI IS62C256 ® WRITE CYCLE SWITCHING CHARACTERISTICS(1,3) (Over Operating Range) Symbol -45 ns Min. Max. Parameter -70ns Min. Max. Unit tWC Write Cycle Time 45 — 70 — ns tSCS CS to Write End 35 — 60 — ns tAW Address Setup Time to Write End 25 — 60 — ns tHA Address Hold from Write End 0 — 0 — ns Address Setup Time 0 — 0 — ns tPWE WE Pulse Width 25 — 55 — ns tSD Data Setup to Write End 20 — 30 — ns tHD Data Hold from Write End 0 — 0 — ns tSA (4) Notes: 1. Test conditions assume signal transition times of 5 ns or less, timing reference levels of 1.5V, input pulse levels of 0 to 3.0V and output loading specified in Figure 1. 2. Tested with the load in Figure 2. Transition is measured ±500 mV from steady-state voltage. Not 100% tested. 3. The internal write time is defined by the overlap of CS LOW and WE LOW. All signals must be in valid states to initiate a Write, but any one can go inactive to terminate the Write. The Data Input Setup and Hold timing are referenced to the rising or falling edge of the signal that terminates the write. 4. Tested with OE HIGH. AC WAVEFORMS WRITE CYCLE NO. 1 (CS Controlled, OE is HIGH or LOW) (1 ) t WC VALID ADDRESS ADDRESS t SA t SCS t HA CS t AW t PWE1 t PWE2 WE t HZWE DOUT DATA UNDEFINED t LZWE HIGH-Z t SD DIN t HD DATAIN VALID CS_WR1.eps 6 Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99 ISSI IS62C256 ® AC WAVEFORMS WRITE CYCLE NO. 2 (OE is HIGH During Write Cycle) (1,2) t WC ADDRESS VALID ADDRESS t HA OE CS LOW t AW t PWE1 WE t SA DOUT t HZWE t LZWE HIGH-Z DATA UNDEFINED t SD t HD DATAIN VALID DIN CS_WR2.eps WRITE CYCLE NO. 3 (OE is LOW During Write Cycle) (1) t WC ADDRESS VALID ADDRESS OE LOW CS LOW t HA t AW t PWE2 WE t SA DOUT t HZWE DATA UNDEFINED t LZWE HIGH-Z t SD DIN t HD DATAIN VALID CS_WR3.eps Notes: 1. The internal write time is defined by the overlap of Cs LOW and WE LOW. All signals must be in valid states to initiate a Write, but any one can go inactive to terminate the Write. The Data Input Setup and Hold timing are referenced to the rising or falling edge of the signal that terminates the write. 2. I/O will assume the High-Z state if OE = VIH. Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99 7 ISSI IS62C256 ORDERING INFORMATION Commerical Range: 0°C to +70°C ORDERING INFORMATION Industrial Range: –40°C to +85°C Speed (ns) Speed (ns) Order Part No. Package 45 IS62C256-45T IS62C256-45U TSOP Plastic SOP 70 IS62C256-70T IS62C256-70U TSOP Plastic SOP Order Part No. Package 45 IS62C256-45TI IS62C256-45UI TSOP Plastic SOP 70 IS62C256-70TI IS62C256-70UI TSOP Plastic SOP ISSI ® ® Integrated Silicon Solution, Inc. 2231 Lawson Lane Santa Clara, CA 95054 Tel: 1-800-379-4774 Fax: (408) 588-0806 E-mail: [email protected] www.issi.com 8 Integrated Silicon Solution, Inc. — 1-800-379-4774 SR072-1E 05/12/99