Rev 0; 8/06 3.3V Single-Piece 16Mb Nonvolatile SRAM Features The DS2070W is a 16Mb reflowable nonvolatile (NV) SRAM, which consists of a static RAM (SRAM), an NV controller, and an internal rechargeable manganese lithium (ML) battery. These components are encased in a surface-mount module with a 256-ball BGA footprint. Whenever VCC is applied to the module, it recharges the ML battery, powers the SRAM from the external power source, and allows the contents of the SRAM to be modified. When VCC is powered down or out-of-tolerance, the controller write-protects the SRAM’s contents and powers the SRAM from the battery. The DS2070W also contains a power-supply monitor output, RST, which can be used as a CPU supervisor for a microprocessor. ♦ Single-Piece, Reflowable, PBGA Package Footprint ♦ Internal ML Battery and Charger ♦ Unconditionally Write-Protects SRAM when VCC is Out-of-Tolerance ♦ Automatically Switches to Battery Supply when VCC Power Failures Occur ♦ Internal Power-Supply Monitor Detects Power Fail Below Nominal VCC (3.3V) ♦ Reset Output can be Used as a CPU Supervisor for a Microprocessor ♦ Industrial Temperature Range (-40°C to +85°C) ♦ UL Recognized Applications RAID Systems and Servers Industrial Controllers POS Terminals Routers/Switches Data-Acquisition Systems Gaming Fire Alarms PLC (27mm)2 Pin Configuration appears at end of data sheet. Ordering Information PART DS2070W-100# TEMP RANGE PIN-PACKAGE SPEED (ns) SUPPLY TOLERANCE -40°C to +85°C 256 Ball (27mm)2 BGA Module 100 3.3V ±0.3V #Denotes a RoHS-compliant device that may include lead that is exempt under the RoHS requirements. Typical Operating Circuit (CE) CE (WR) WE (RD) OE DS2070W MICROPROCESSOR OR DSP 2048k x 8 NV SRAM DATA 8 BITS ADDRESS 21 BITS (INT) DQ0–DQ7 A0–A20 RST ______________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 DS2070W General Description DS2070W 3.3V Single-Piece 16Mb Nonvolatile SRAM ABSOLUTE MAXIMUM RATINGS Voltage on Any Pin Relative to Ground .................-0.3V to +4.6V Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range ...............................-40°C to +85°C Soldering Temperature .....................See IPC/JEDEC J-STD-020 Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS (TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS MIN TYP 3.3 MAX UNITS Supply Voltage VCC 3.0 3.6 V Input Logic 1 VIH 2.2 VCC V Input Logic 0 VIL 0 0.4 V MAX UNITS µA DC ELECTRICAL CHARACTERISTICS (VCC = 3.3V ±0.3V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS MIN TYP Input Leakage Current IIL -1.0 +1.0 I/O Leakage Current IIO CE = VCC -1.0 +1.0 Output-Current High IOH At 2.4V -1.0 IOL At 0.4V 2.0 mA At 0.4V (Note 1) 10.0 mA Output-Current Low Output-Current Low RST Standby Current Operating Current Write-Protection Voltage IOL RST ICCS1 CE = 2.2V 0.5 7 ICCS2 CE = VCC - 0.2V 0.2 5 ICCO1 tRC = 200ns, outputs open VTP µA mA mA 50 mA 2.8 2.9 3.0 V MIN TYP MAX UNITS CAPACITANCE (TA = +25°C.) PARAMETER Input Capacitance Input/Output Capacitance SYMBOL CONDITIONS CIN Not tested 7 pF COUT Not tested 7 pF AC ELECTRICAL CHARACTERISTICS (VCC = 3.3V ±0.3V, TA = -40°C to +85°C.) PARAMETER Read Cycle Time SYMBOL CONDITIONS tRC MIN MAX 100 UNITS ns tACC 100 ns OE to Output Valid tOE 50 ns CE to Output Valid tCO 100 ns Access Time 2 _____________________________________________________________________ 3.3V Single-Piece 16Mb Nonvolatile SRAM DS2070W AC ELECTRICAL CHARACTERISTICS (continued) (VCC = 3.3V ±0.3V, TA = -40°C to +85°C.) PARAMETER SYMBOL CONDITIONS OE or CE to Output Active tCOE (Note 2) Output High Impedance from Deselection tOD (Note 2) MIN MAX 5 UNITS ns 35 ns Output Hold from Address Change tOH 5 Write Cycle Time tWC 100 ns Write Pulse Width tWP (Note 3) 75 ns 0 ns tWR1 (Note 4) 5 tWR2 (Note 5) 20 Output High Impedance from WE tODW (Note 2) Output Active from WE tOEW (Note 2) 5 ns tDS (Note 6) 40 ns tDH1 (Note 4) 0 tDH2 (Note 5) 20 tAW Address Setup Time Write Recovery Time Data Setup Time Data Hold Time ns ns 35 ns ns POWER-DOWN/POWER-UP TIMING (TA = -40°C to +85°C.) SYMBOL PARAMETER VCC Fail Detect to CE and WE Inactive tPD CONDITIONS MIN TYP (Note 7) MAX UNITS 1.5 µs VCC Slew from VTP to 0V tF 150 µs VCC Slew from 0V to VTP tR 150 µs VCC Valid to CE and WE Inactive tPU 2 ms VCC Valid to End of Write Protection tREC 125 ms VCC Fail Detect to RST Active tRPD (Note 1) 3.0 µs VCC Valid to RST Inactive tRPU (Note 1) 225 350 525 ms MIN TYP MAX UNITS 2 3 DATA RETENTION (TA = +25°C.) SYMBOL PARAMETER Expected Data-Retention Time (Per Charge) tDR CONDITIONS (Note 8) years AC TEST CONDITIONS Input Pulse Levels: VIL = 0.0V, VIH = 3.0V Input Pulse Rise and Fall Times: 5ns Input and Output Timing Reference Level: 1.5V Output Load: 1 TTL Gate + CL (100pF) including scope and jig _____________________________________________________________________ 3 3.3V Single-Piece 16Mb Nonvolatile SRAM DS2070W Read Cycle tRC ADDRESSES VIH VIH VIH VIL VIL VIL tOH tACC VIH CE VIH tCO VIL tOD VIH OE tOE VIH VIL tOD tCOE tCOE DOUT VOH VOL OUTPUT DATA VALID (SEE NOTE 9.) 4 _____________________________________________________________________ VOH VOL 3.3V Single-Piece 16Mb Nonvolatile SRAM tWC ADDRESSES VIH VIL VIH VIL VIH VIL tAW CE VIL VIL tWP WE VIH VIL tWR1 VIL VIH tOEW tODW HIGH IMPEDANCE DOUT tDS tDH1 VIH VIH DIN DATA IN STABLE VIL VIL (SEE NOTES 2, 3, 4, 6, 10–13.) Write Cycle 2 tWC ADDRESSES VIH VIL tAW CE VIH VIH VIL VIL tWR2 tWP VIH VIH VIL WE VIL VIL VIL VIL tODW tCOE DOUT tDH2 tDS VIH VIH DIN DATA IN STABLE VIL VIL (SEE NOTES 2, 3, 5, 6, 10–13.) _____________________________________________________________________ 5 DS2070W Write Cycle 1 3.3V Single-Piece 16Mb Nonvolatile SRAM DS2070W Power-Down/Power-Up Condition VCC VTP tDR ~2.5V tF tR tREC tPD SLEWS WITH VCC CE, WE tPU VIH BACKUP CURRENT SUPPLIED FROM LITHIUM BATTERY tRPD tRPU RST VOL VOL (SEE NOTES 1, 7.) Note 1: RST is an open-drain output and cannot source current. An external pullup resistor should be connected to this pin to realize a logic-high level. Note 2: These parameters are sampled with a 5pF load and are not 100% tested. Note 3: tWP is specified as the logical AND of CE and WE. tWP is measured from the latter of CE or WE going low to the earlier of CE or WE going high. Note 4: tWR1 and tDH1 are measured from WE going high. Note 5: tWR2 and tDH2 are measured from CE going high. Note 6: tDS is measured from the earlier of CE or WE going high. Note 7: In a power-down condition, the voltage on any pin cannot exceed the voltage on VCC. Note 8: The expected tDR is defined as accumulative time in the absence of VCC starting from the time power is first applied by the user. Minimum expected data-retention time is based on a maximum of two +230°C convection solder reflow exposures, followed by a fully charged cell. Full charge occurs with the initial application of VCC for a minimum of 96 hours. This parameter is assured by component selection, process control, and design. It is not measured directly in production testing. Note 9: WE is high for a read cycle. Note 10: OE = VIH or VIL. If OE = VIH during write cycle, the output buffers remain in a high-impedance state. Note 11: If the CE low transition occurs simultaneously with or later than the WE low transition, the output buffers remain in a highimpedance state during this period. Note 12: If the CE high transition occurs prior to or simultaneously with the WE high transition, the output buffers remain in a highimpedance state during this period. Note 13: If WE is low or the WE low transition occurs prior to or simultaneously with the CE low transition, the output buffers remain in a high-impedance state during this period. Note 14: DS2070W BGA modules are recognized by Underwriters Laboratory (UL) under file E99151. 6 _____________________________________________________________________ 3.3V Single-Piece 16Mb Nonvolatile SRAM SUPPLY CURRENT vs. SUPPLY VOLTAGE 4 1MHz ADDRESSACTIVATED 100% DUTY CYCLE 800 700 600 2 500 0 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.0 3.1 3.2 3.3 3.4 3.5 -0.5 -1.0 35 60 DS2070W toc03 0.4 0.6 0.8 1.0 DQ VOH vs. DQ IOH DS2070W toc05 3.5 2.90 VCC = 3.3V 3.3 2.95 3.1 2.9 2.85 2.7 85 2.5 -40 -15 10 35 60 85 -5 -4 -3 -2 -1 0 TEMPERATURE (°C) IOH (mA) DQ VOL vs. DQ IOL RST OUTPUT-VOLTAGE LOW vs. OUTPUT-CURRENT LOW RST VOLTAGE vs. VCC DURING POWER-UP VCC = 2.8V 0.5 VOL (V) 0.4 0.2 0.3 0.2 0.1 0.1 0 0 2 IOL (mA) 3 4 5 4.0 RST VOLTAGE WITH PULLUP RESISTOR (V) DS2070W toc07 0.6 0.3 VOL (V) 0.2 TEMPERATURE (°C) VCC = 3.3V 1 VCHARGE 0 2.80 0 1 3.6 VOH (V) WRITE PROTECT, VTP (V) 0 0.4 2 VTP vs. TEMPERATURE 0.5 10 3 DELTA V BELOW VCHARGE (V) 3.00 DS2070W toc04 VCHARGE PERCENT CHANGE FROM +25°C (%) VCC = 3.3V, VBAT = VCHARGE -15 4 VCC (V) VCHARGE PERCENT CHANGE vs. TEMPERATURE -40 5 0 VCC (V) 1.0 6 DS2070W toc06 5MHz ADDRESSACTIVATED 100% DUTY CYCLE 1MHz CE-ACTIVATED 50% DUTY CYCLE VCC = CE = 3.3V 7 DS2070W toc09 6 900 8 BATTERY CHARGER CURRENT, ICHARGE (mA) 5MHz CE-ACTIVATED 50% DUTY CYCLE VCC = CE = 3.3V, VBAT = VCHARGE, OSC = ON DS2070W toc08 SUPPLY CURRENT (mA) 10 SUPPLY CURRENT (µA) TA = +25°C 8 1000 DS2070W toc01 12 BATTERY CHARGER CURRENT vs. BATTERY VOLTAGE DS2070W toc02 SUPPLY CURRENT vs. OPERATING FREQUENCY TA = +25°C 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 0 5 10 IOL (mA) 15 20 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 VCC POWER-UP (V) _____________________________________________________________________ 7 DS2070W Typical Operating Characteristics (VCC = +3.3V, TA = +25°C, unless otherwise noted.) DS2070W 3.3V Single-Piece 16Mb Nonvolatile SRAM Pin Description BALLS NAME DESCRIPTION BALLS NAME DESCRIPTION A1, A2, A3, A4 GND Ground N17, N18, N19, N20 A5 Address Input 5 B1, B2, B3, B4 N.C. No Connection P17, P18, P19, P20 A4 Address Input 4 C1, C2, C3, C4 A15 Address Input 15 R17, R18, R19, R20 A3 Address Input 3 D1, D2, D3, D4 A16 Address Input 16 T17, T18, T19, T20 A2 Address Input 2 E1, E2, E3, E4 RST Open-Drain Reset Output U17, U18, U19, U20 A1 Address Input 1 F1, F2, F3, F4 VCC Supply Voltage V17, V18, V19, V20 A0 Address Input 0 G1, G2, G3, G4 WE Write-Enable Input W17, W18, W19, W20 GND H1, H2, H3, H4 OE Output-Enable Input Y17, Y18, Y19, Y20 GND Ground J1, J2, J3, J4 CE Chip-Enable Input A5, B5, C5, D5 N.C. No Connection Ground K1, K2, K3, K4 DQ7 Data Input/Output 7 A6, B6, C6, D6 N.C. No Connection L1, L2, L3, L4 DQ6 Data Input/Output 6 A7, B7, C7, D7 N.C. No Connection M1, M2, M3, M4 DQ5 Data Input/Output 5 A8, B8, C8, D8 N.C. No Connection N1, N2, N3, N4 DQ4 Data Input/Output 4 A9, B9, C9, D9 N.C. No Connection P1, P2, P3, P4 DQ3 Data Input/Output 3 A10, B10, C10, D10 N.C. No Connection R1, R2, R3, R4 DQ2 Data Input/Output 2 A11, B11, C11, D11 N.C. No Connection T1, T2, T3, T4 DQ1 Data Input/Output 1 A12, B12, C12, D12 N.C. No Connection U1, U2, U3, U4 DQ0 Data Input/Output 0 A13, B13, C13, D13 N.C. No Connection V1, V2, V3, V4 GND Ground A14, B14, C14, D14 N.C. No Connection W1, W2, W3, W4 GND Ground A15, B15, C15, D15 A19 Address Input 19 Y1, Y2, Y3, Y4 GND Ground A16, B16, C16, D16 A20 Address Input 20 A17, A18, A19, A20 GND Ground U5, V5, W5, Y5 N.C. No Connection B17, B18, B19, B20 A18 Address Input 18 U6, V6, W6, Y6 N.C. No Connection C17, C18, C19, C20 A17 Address Input 17 U7, V7, W7, Y7 N.C. No Connection D17, D18, D19, D20 A14 Address Input 14 U8, V8, W8, Y8 N.C. No Connection E17, E18, E19, E20 A13 Address Input 13 U9, V9, W9, Y9 N.C. No Connection F17, F18, F19, F20 A12 Address Input 12 U10, V10, W10, Y10 N.C. No Connection G17, G18, G19, G20 A11 Address Input 11 U11, V11, W11, Y11 N.C. No Connection H17, H18, H19, H20 A10 Address Input 10 U12, V12, W12, Y12 N.C. No Connection J17, J18, J19, J20 A9 Address Input 9 U13, V13, W13, Y13 N.C. No Connection K17, K18, K19, K20 A8 Address Input 8 U14, V14, W14, Y14 N.C. No Connection L17, L18, L19, L20 A7 Address Input 7 U15, V15, W15, Y15 N.C. No Connection M17, M18, M19, M20 A6 Address Input 6 U16, V16, W16, Y16 N.C. No Connection 8 _____________________________________________________________________ 3.3V Single-Piece 16Mb Nonvolatile SRAM CE RST DELAY TIMING CIRCUITRY VTP REF CHARGER UNINTERRUPTED POWER SUPPLY FOR THE SRAM CURRENT-LIMITING RESISTOR VCC VCC CE OE WE VSW REF SRAM DQ0–DQ7 REDUNDANT LOGIC ML GND CURRENT-LIMITING RESISTOR REDUNDANT SERIES FET BATTERY-CHARGING/SHORTING PROTECTION CIRCUITRY (UL RECOGNIZED) OE DS2070W WE A0–A20 Detailed Description The DS2070W is a 16Mb (2048kb x 8 bits) fully static, NV memory similar in function and organization to the DS1270W NV SRAM, but containing a rechargeable ML battery. The DS2070W NV SRAM constantly monitors VCC for an out-of-tolerance condition. When such a condition occurs, the lithium energy source is automatically switched on and write protection is unconditionally enabled to prevent data corruption. There is no limit to the number of write cycles that can be executed and no additional support circuitry is required for microprocessor interfacing. This device can be used in place of SRAM, EEPROM, or flash components. The DS2070W assembly consists of a low-power SRAM, an ML battery, and an NV controller with a battery charger, integrated on a standard 256-ball, (27mm)2 BGA substrate. Unlike other surface-mount NV memory modules that require the battery to be removable for soldering, the internal ML battery can tolerate exposure to convection reflow soldering temperatures allowing this single-piece component to be handled with standard BGA assembly techniques. The DS2070W also contains a power-supply monitor output, RST, which can be used as a CPU supervisor for a microprocessor. _____________________________________________________________________ 9 DS2070W Functional Diagram DS2070W 3.3V Single-Piece 16Mb Nonvolatile SRAM Memory Operation Truth Table WE CE OE MODE ICC OUTPUTS 1 0 0 Read Active Active 1 0 1 Read Active High Impedance 0 0 X Write Active High Impedance X 1 X Standby Standby High Impedance X = Don’t care. Read Mode The DS2070W executes a read cycle whenever WE (write enable) is inactive (high) and CE (chip enable) is active (low). The unique address specified by the 21 address inputs (A0 to A20) defines which of the 2,097,152 bytes of data is to be accessed. Valid data will be available to the eight data output drivers within tACC (access time) after the last address input signal is stable, providing that CE and OE (output enable) access times are also satisfied. If CE and OE access times are not satisfied, then data access must be measured from the later-occurring signal (CE or OE) and the limiting parameter is either tCO for CE or tOE for OE, rather than address access. Write Mode The DS2070W executes a write cycle whenever the CE and WE signals are active (low) after address inputs are stable. The later-occurring falling edge of CE or WE will determine the start of the write cycle. The write cycle is terminated by the earlier rising edge of CE or WE. All address inputs must be kept valid throughout the write cycle. WE must return to the high state for a minimum recovery time (tWR) before another cycle can be initiated. The OE control signal should be kept inactive (high) during write cycles to avoid bus contention. However, if the output drivers have been enabled (CE and OE active) then WE will disable the outputs in tODW from its falling edge. Data-Retention Mode The DS2070W provides full functional capability for VCC greater than 3.0V and write-protects by 2.8V. Data is maintained in the absence of VCC without additional support circuitry. The NV static RAM constantly monitors V CC. Should the supply voltage decay, the NV SRAM automatically write-protects itself. All inputs become “don’t care”, and all data outputs become high impedance. As V CC falls below approximately 2.5V (VSW), the power-switching circuit connects the lithium 10 energy source to the RAM to retain data. During powerup, when VCC rises above VSW, the power-switching circuit connects external VCC to the RAM and disconnects the lithium energy source. Normal RAM operation can resume after VCC exceeds V TP for a minimum duration of tREC. Battery Charging When VCC is greater than VTP, an internal regulator charges the battery. The UL-approved charger circuit includes short-circuit protection and a temperature-stabilized voltage reference for on-demand charging of the internal battery. Typical data-retention expectations of 3 years per charge cycle are achievable. A maximum of 96 hours of charging time is required to fully charge a depleted battery. System Power Monitoring When the external VCC supply falls below the selected out-of-tolerance trip point, the output RST is forced active (low). Once active, the RST is held active until the VCC supply has fallen below that of the internal battery. On power-up, the RST output is held active until the external supply is greater than the selected trip point and one reset timeout period (tRPU) has elapsed. This is sufficiently longer than tREC to ensure that the SRAM is ready for access by the microprocessor. Freshness Seal and Shipping The DS2070W is shipped from Dallas Semiconductor with the lithium battery electrically disconnected, guaranteeing that no battery capacity has been consumed during transit or storage. As shipped, the lithium battery is ~60% charged, and no preassembly charging operations should be attempted. When VCC is first applied at a level greater than VTP, the lithium battery is enabled for backup operation. A 96-hour initial battery charge time is recommended for new system installations. ____________________________________________________________________ 3.3V Single-Piece 16Mb Nonvolatile SRAM PROFILE FEATURE Average ramp-up rate (TL to TP) Preheat - Temperature min (TSmin) - Temperature max (TSmax) - Time (min to max) (tS) Sn-Pb EUTECTIC ASSEMBLY 3°C/second max +100°C +150°C 60 to 120 seconds Peak temperature (TP) +183°C 60 to 150 seconds +225 +0/-5°C Time within 5°C of actual peak temperature (TP) 10 to 30 seconds Ramp-down rate 6°C/second max Time +25°C to peak temperature Power-Supply Decoupling To achieve the best results when using the DS2070W, decouple the power supply with a 0.1µF capacitor. Use a high-quality, ceramic surface-mount capacitor if possible. Surface-mount components minimize lead inductance, which improves performance, while ceramic capacitors have adequately high frequency response for decoupling applications. Using the Open-Drain RST Output The RST output is open drain, and therefore requires a pullup resistor to realize a high logic output level. Pullup resistor values between 1kΩ and 10kΩ are typical. TSmax to TL - Ramp-up rate Time maintained above: - Temperature (TL) - Time (tL) Applications Information 6 minutes max Note: All temperatures refer to top side of the package, measured on the package body surface. Battery Charging/Lifetime The DS2070W charges an ML battery to maximum capacity in approximately 96 hours of operation when VCC is greater than VTP. Once the battery is charged, its lifetime depends primarily on the VCC duty cycle. The DS2070W can maintain data from a single, initial charge for up to 3 years. Once recharged, this deepdischarge cycle can be repeated up to 20 times, producing a worst-case service life of 60 years. More typical duty cycles are of shorter duration, enabling the DS2070W to be charged hundreds of times, therefore extending the service life well beyond 60 years. Recommended Cleaning Procedures The DS2070W may be cleaned using aqueous-based cleaning solutions. No special precautions are needed when cleaning boards containing a DS2070W module. Removal of the topside label violates the environmental integrity of the package and voids the warranty of the product. ____________________________________________________________________ 11 DS2070W Recommended Reflow Temperature Profile Pin Configuration TOP VIEW 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 D A16 A14 D E RST A13 E F VCC A12 F G WE A11 G H OE A10 H J CE A9 J K DQ7 A8 K L DQ6 A7 L M DQ5 A6 M N DQ4 A5 N P DQ3 A4 P R DQ2 A3 R T DQ1 A2 T U DQ0 A1 U V GND A0 V W GND GND W Y GND GND Y 1 2 A20 C A19 A17 N.C. A15 N.C. C N.C. B N.C. A18 N.C. N.C. N.C. B N.C. A N.C. GND N.C. GND N.C. A 3 4 5 6 7 8 9 10 11 12 13 14 15 N.C. N.C. N.C. N.C. N.C. N.C. N.C. N.C. N.C. N.C. N.C. DS2070W N.C. DS2070W 3.3V Single-Piece 16Mb Nonvolatile SRAM 16 17 18 19 20 Package Information For the latest package outline information, go to www.maxim-ic.com/DallasPackInfo. Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2006 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc. is a registered trademark of Dallas Semiconductor Corporation. Springer