H CAT24WC256 EE GEN FR ALO 256K-Bit I2C Serial CMOS EEPROM LE (CAT24WC256 not recommended for new designs. See CAT24FC256 data sheet.) A D F R E ETM FEATURES ■ 1MHz I2C bus compatible* ■ Write protect feature – entire array protected when WP at VIH ■ 1.8 to 6 volt operation ■ Low power CMOS technology ■ 100,000 program/erase cycles ■ 64-byte page write buffer ■ 100 year data retention ■ Self-timed write cycle with auto-clear ■ 8-pin DIP or 8-pin SOIC ■ Commercial, industrial and automotive ■ "Green" package options available temperature ranges DESCRIPTION features a 64-byte page write buffer. The device operates via the I2C bus serial interface and is available in 8pin DIP or 8-pin SOIC packages. The CAT24WC256 is a 256K-bit Serial CMOS EEPROM internally organized as 32,768 words of 8 bits each. Catalyst’s advanced CMOS technology substantially reduces device power requirements. The CAT24WC256 PIN CONFIGURATION EXTERNAL LOAD DIP Package (P, L) A0 A1 NC VSS BLOCK DIAGRAM 1 2 8 7 VCC WP 3 4 6 5 SCL SDA SENSE AMPS SHIFT REGISTERS DOUT ACK VCC WORD ADDRESS BUFFERS VSS COLUMN DECODERS 512 SOIC Package (J, W, K, X) A0 1 8 A1 2 3 4 7 6 5 NC VSS SDA START/STOP LOGIC VCC WP SCL XDEC SDA WP 512 EEPROM 512X512 CONTROL LOGIC PIN FUNCTIONS Pin Name Function A0, A1 Address Inputs SDA Serial Data/Address SCL Serial Clock WP Write Protect VCC +1.8V to +6.0V Power Supply VSS Ground NC No Connect DATA IN STORAGE HIGH VOLTAGE/ TIMING CONTROL SCL A0 A1 STATE COUNTERS SLAVE ADDRESS COMPARATORS * Catalyst Semiconductor is licensed by Philips Corporation to carry the I2C Bus Protocol. © 2004 by Catalyst Semiconductor, Inc. Characteristics subject to change without notice 1 Doc. No. 1031, Rev. F CAT24WC256 ABSOLUTE MAXIMUM RATINGS* *COMMENT Temperature Under Bias ................. –55°C to +125°C Stresses above 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 outside of those listed in the operational sections of this specification is not implied. Exposure to any absolute maximum rating for extended periods may affect device performance and reliability. Storage Temperature ....................... –65°C to +150°C Voltage on Any Pin with Respect to Ground(1) ........... –2.0V to +VCC + 2.0V VCC with Respect to Ground ............... –2.0V to +7.0V Package Power Dissipation Capability (Ta = 25°C) ................................... 1.0W Lead Soldering Temperature (10 secs) ............ 300°C Output Short Circuit Current(2) ........................ 100mA RELIABILITY CHARACTERISTICS Symbol Parameter (3) Endurance NEND TDR (3) Reference Test Method Min Typ Max MIL-STD-883, Test Method 1033 100,000 Units Cycles/Byte Data Retention MIL-STD-883, Test Method 1008 100 Years VZAP(3) ESD Susceptibility MIL-STD-883, Test Method 3015 2000 Volts ILTH(3)(4) Latch-up JEDEC Standard 17 100 mA D.C. OPERATING CHARACTERISTICS VCC = +1.8V to +6.0V, unless otherwise specified. Symbol Parameter Test Conditions ICC1 Power Supply Current - Read ICC2 Power Supply Current - Write ISB(5) Min Typ Max Units fSCL = 100 KHz VCC=5V 1 mA fSCL = 100KHz VCC=5V 3 mA Standby Current VIN = GND or VCC VCC=5V 1 µA ILI Input Leakage Current VIN = GND to VCC 1 µA ILO Output Leakage Current VOUT = GND to VCC 1 µA VIL Input Low Voltage –1 VCC x 0.3 V VIH Input High Voltage VCC x 0.7 VCC + 0.5 V VOL1 Output Low Voltage (VCC = +3.0V) IOL = 3.0 mA 0.4 V VOL2 Output Low Voltage (VCC = +1.8V) IOL = 1.5 mA 0.5 V Max Units CAPACITANCE TA = 25°C, f = 1.0 MHz, VCC = 5V Symbol Test Conditions Min Typ CI/O(3) Input/Output Capacitance (SDA) VI/O = 0V 8 pF CIN(3) Input Capacitance (SCL, WP, A0, A1) VIN = 0V 6 pF Note: (1) The minimum DC input voltage is –0.5V. During transitions, inputs may undershoot to –2.0V for periods of less than 20 ns. Maximum DC voltage on output pins is VCC +0.5V, which may overshoot to VCC + 2.0V for periods of less than 20ns. (2) Output shorted for no more than one second. No more than one output shorted at a time. (3) This parameter is tested initially and after a design or process change that affects the parameter. (4) Latch-up protection is provided for stresses up to 100 mA on address and data pins from –1V to VCC +1V. (5) Maximum standby current (ISB ) = 10µA for the Automotive and Extended Automotive temperature range. Doc. No. 1031, Rev. F 2 CAT24WC256 A.C. CHARACTERISTICS VCC = +1.8V to +6V, unless otherwise specified Output Load is 1 TTL Gate and 100pF Read & Write Cycle Limits Symbol Parameter VCC=1.8V - 6.0V VCC=2.5V - 6.0V VCC=3.0V - 5.5V Min Max Min Min Units 1000 kHz 0.55 µs Clock Frequency tAA SCL Low to SDA Data Out and ACK Out 0.1 tBUF(2) Time the Bus Must be Free Before a New Transmission Can Start 4.7 1.2 0.5 µs tHD:STA Start Condition Hold Time 4.0 0.6 0.25 µs tLOW Clock Low Period 4.7 1.2 0.6 µs tHIGH Clock High Period 4.0 0.6 0.4 µs tSU:STA Start Condition Setup Time (for a Repeated Start Condition) 4.0 0.6 0.25 µs tHD:DAT Data In Hold Time 0 0 0 ns tSU:DAT Data In Setup Time 100 100 100 ns tR(2) SDA and SCL Rise Time 1.0 0.3 0.3 µs SDA and SCL Fall Time 300 300 100 ns tF 3.5 400 Max FSCL (2) 100 Max 0.05 0.9 0.05 tSU:STO Stop Condition Setup Time 4.7 0.6 0.25 µs tDH Data Out Hold Time 100 50 50 ns tWR Write Cycle Time 10 10 10 ms Max Units Power-Up Timing (2)(3) Symbol Parameter Min Typ tPUR Power-Up to Read Operation 1 ms tPUW Power-Up to Write Operation 1 ms Note: (1) AC measurement conditions: RL (connects to VCC): 0.3VCC to 0.7 VCC Input rise and fall times: < 50ns Input and output timing reference voltages: 0.5 VCC (2) This parameter is tested initially and after a design or process change that affects the parameter. (3) tPUR and tPUW are the delays required from the time VCC is stable until the specified operation can be initiated. interface circuits are disabled, SDA is allowed to remain high, and the device does not respond to its slave address. The write cycle time is the time from a valid stop condition of a write sequence to the end of the internal program/erase cycle. During the write cycle, the bus 3 Doc. No. 1031, Rev. F CAT24WC256 SDA: Serial Data/Address FUNCTIONAL DESCRIPTION The bidirectional serial data/address pin is used to transfer all data into and out of the device. The SDA pin is an open drain output and can be wire-ORed with other open drain or open collector outputs. The CAT24WC256 supports the I2C Bus data transmission protocol. This Inter-Integrated Circuit Bus protocol defines any device that sends data to the bus to be a transmitter and any device receiving data to be a receiver. The transfer is controlled by the Master device which generates the serial clock and all START and STOP conditions for bus access. The CAT24WC256 operates as a Slave device. Both the Master device and Slave device can operate as either transmitter or receiver, but the Master device controls which mode is activated. WP: Write Protect This input, when tied to GND, allows write operations to the entire memory. When this pin is tied to Vcc, the entire memory is write protected. When left floating, memory is unprotected. A0, A1: Device Address Inputs PIN DESCRIPTIONS These pins are hardwired or left connected. When hardwired, up to four CAT24WC256's may be addressed on a single bus system. When the pins are left unconnected, the default values are zero. SCL: Serial Clock The serial clock input clocks all data transferred into or out of the device. Figure 1. Bus Timing tF tHIGH tLOW tR tLOW SCL tSU:STA tHD:DAT tHD:STA tSU:DAT tSU:STO SDA IN tAA tBUF tDH SDA OUT Figure 2. Write Cycle Timing SCL SDA 8TH BIT BYTE n ACK tWR STOP CONDITION START CONDITION Figure 3. Start/Stop Timing SDA SCL START BIT Doc. No. 1031, Rev. F STOP BIT 4 ADDRESS CAT24WC256 I2C BUS PROTOCOL many as four devices on the same bus. These bits must compare to their hardwired input pins. The last bit of the slave address specifies whether a Read or Write operation is to be performed. When this bit is set to 1, a Read operation is selected, and when set to 0, a Write operation is selected. The features of the I2C bus protocol are defined as follows: (1) Data transfer may be initiated only when the bus is not busy. (2) During a data transfer, the data line must remain stable whenever the clock line is high. Any changes in the data line while the clock line is high will be interpreted as a START or STOP condition. After the Master sends a START condition and the slave address byte, the CAT24WC256 monitors the bus and responds with an acknowledge (on the SDA line) when its address matches the transmitted slave address. The CAT24WC256 then performs a Read or Write operation depending on the state of the R/W bit. START Condition The START Condition precedes all commands to the device, and is defined as a HIGH to LOW transition of SDA when SCL is HIGH. The CAT24WC256 monitors the SDA and SCL lines and will not respond until this condition is met. Acknowledge After a successful data transfer, each receiving device is required to generate an acknowledge. The Acknowledging device pulls down the SDA line during the ninth clock cycle, signaling that it received the 8 bits of data. STOP Condition A LOW to HIGH transition of SDA when SCL is HIGH determines the STOP condition. All operations must end with a STOP condition. The CAT24WC256 responds with an acknowledge after receiving a START condition and its slave address. If the device has been selected along with a write operation, it responds with an acknowledge after receiving each 8bit byte. DEVICE ADDRESSING The bus Master begins a transmission by sending a START condition. The Master sends the address of the particular slave device it is requesting. The five most significant bits of the 8-bit slave address are fixed as 10100(Fig. 5). The CAT24WC256 uses the next two bits as address bits. The address bits A1 and A0 allow as When the CAT24WC256 begins a READ mode it transmits 8 bits of data, releases the SDA line, and monitors the line for an acknowledge. Once it receives this acknowledge, the CAT24WC256 will continue to transmit data. If no acknowledge is sent by the Master, the device Figure 4. Acknowledge Timing SCL FROM MASTER 1 8 9 DATA OUTPUT FROM TRANSMITTER DATA OUTPUT FROM RECEIVER ACKNOWLEDGE START Figure 5. Slave Address Bits 1 0 1 0 0 5 A1 A0 R/W Doc. No. 1031, Rev. F CAT24WC256 terminates data transmission and waits for a STOP condition. If the Master transmits more than 64 bytes before sending the STOP condition, the address counter ‘wraps around’, and previously transmitted data will be overwritten. WRITE OPERATIONS When all 64 bytes are received, and the STOP condition has been sent by the Master, the internal programming cycle begins. At this point, all received data is written to the CAT24WC256 in a single write cycle. Byte Write In the Byte Write mode, the Master device sends the START condition and the slave address information (with the R/W bit set to zero) to the Slave device. After the Slave generates an acknowledge, the Master sends two 8-bit address words that are to be written into the address pointers of the CAT24WC256. After receiving another acknowledge from the Slave, the Master device transmits the data to be written into the addressed memory location. The CAT24WC256 acknowledges once more and the Master generates the STOP condition. At this time, the device begins an internal programming cycle to nonvolatile memory. While the cycle is in progress, the device will not respond to any request from the Master device. Acknowledge Polling Disabling of the inputs can be used to take advantage of the typical write cycle time. Once the stop condition is issued to indicate the end of the host's write operation, CAT24WC256 initiates the internal write cycle. ACK polling can be initiated immediately. This involves issuing the start condition followed by the slave address for a write operation. If CAT24WC256 is still busy with the write operation, no ACK will be returned. If CAT24WC256 has completed the write operation, an ACK will be returned and the host can then proceed with the next read or write operation. Page Write The CAT24WC256 writes up to 64 bytes of data, in a single write cycle, using the Page Write operation. The page write operation is initiated in the same manner as the byte write operation, however instead of terminating after the initial byte is transmitted, the Master is allowed to send up to 63 additional bytes. After each byte has been transmitted, CAT24WC256 will respond with an acknowledge, and internally increment the six low order address bits by one. The high order bits remain unchanged. WRITE PROTECTION The Write Protection feature allows the user to protect against inadvertent programming of the memory array. If the WP pin is tied to VCC, the entire memory array is protected and becomes read only. The CAT24WC256 will accept both slave and byte addresses, but the memory location accessed is protected from programming by the device’s failure to send an acknowledge after the first byte of data is received. Figure 6. Byte Write Timing S T A R T BUS ACTIVITY: MASTER SDA LINE SLAVE ADDRESS BYTE ADDRESS A15–A8 A7–A0 S A C K S T O P DATA P * A C K A C K A C K *=Don't Care Bit Figure 7. Page Write Timing BUS ACTIVITY: MASTER SDA LINE S T A R T SLAVE ADDRESS BYTE ADDRESS A15–A8 A7–A0 S DATA DATA n+63 P * A C K A C K A C K *=Don't Care Bit Doc. No. 1031, Rev. F DATA n S T O P 6 A C K A C K A C K A C K CAT24WC256 The READ operation for the CAT24WC256 is initiated in the same manner as the write operation with one exception, that R/W bit is set to one. Three different READ operations are possible: Immediate/Current Address READ, Selective/Random READ and Sequential READ. wishes to read. After CAT24WC256 acknowledges, the Master device sends the START condition and the slave address again, this time with the R/W bit set to one. The CAT24WC256 then responds with its acknowledge and sends the 8-bit byte requested. The master device does not send an acknowledge but will generate a STOP condition. Immediate/Current Address Read Sequential Read The CAT24WC256’s address counter contains the address of the last byte accessed, incremented by one. In other words, if the last READ or WRITE access was to address N, the READ immediately following would access data from address N+1. If N=E (where E=32767), then the counter will ‘wrap around’ to address 0 and continue to clock out data. After the CAT24WC256 receives its slave address information (with the R/W bit set to one), it issues an acknowledge, then transmits the 8 bit byte requested. The master device does not send an acknowledge, but will generate a STOP condition. The Sequential READ operation can be initiated by either the Immediate Address READ or Selective READ operations. After the CAT24WC256 sends the initial 8bit byte requested, the Master will respond with an acknowledge which tells the device it requires more data. The CAT24WC256 will continue to output an 8-bit byte for each acknowledge sent by the Master. The operation will terminate when the Master fails to respond with an acknowledge, thus sending the STOP condition. READ OPERATIONS The data being transmitted from CAT24WC256 is outputted sequentially with data from address N followed by data from address N+1. The READ operation address counter increments all of the CAT24WC256 address bits so that the entire memory array can be read during one operation. If more than E (where E=32767) bytes are read out, the counter will ‘wrap around’ and continue to clock out data bytes. Selective/Random Read Selective/Random READ operations allow the Master device to select at random any memory location for a READ operation. The Master device first performs a ‘dummy’ write operation by sending the START condition, slave address and byte addresses of the location it Figure 8. Immediate Address Read Timing BUS ACTIVITY: MASTER SDA LINE S T A R T SLAVE ADDRESS DATA S P A C K SCL SDA S T O P 8 N O A C K 9 8TH BIT DATA OUT NO ACK 7 STOP Doc. No. 1031, Rev. F CAT24WC256 Figure 9. Selective Read Timing BUS ACTIVITY: MASTER SDA LINE S T A R T SLAVE ADDRESS S T A R T BYTE ADDRESS A15—A8 A7—A0 * S SLAVE ADDRESS S T O P DATA S A C K A C K P A C K A C K N O A C K *=Don't Care Bit Figure 10. Sequential Read Timing BUS ACTIVITY: MASTER SLAVE ADDRESS DATA n DATA n+1 DATA n+2 S T O P DATA n+x SDA LINE P A C K A C K A C K A C K N O A C K Doc. No. 1031, Rev. F 8 CAT24WC256 ORDERING INFORMATION Prefix CAT Optional Company ID Device # 24WC256 Product Number Suffix K -1.8 I Temperature Range Blank = Commercial (0˚ - 70˚C) I = Industrial (-40˚ - 85˚C) A = Automotive (-40˚ - 105˚C)* Rev B(2) TE13 Tape & Reel Die Revision 24WC256: A, B Package P: PDIP K: SOIC (EIAJ) J: SOIC (JEDEC) L: PDIP (Lead free, Halogen free) W: SOIC, JEDEC (Lead free, Halogen free) X: SOIC, EIAJ (Lead free, Halogen free) Operating Voltage Blank: 2.5 to 6.0V 1.8: 1.8 to 6.0V 3: 3.0V to 5.5V * -40˚ to +125˚C is available upon request Notes: (1) The device used in the above example is a 24WC256KI-1.8TE13 (SOIC, Industrial Temperature, 1.8 Volt to 6 Volt Operating Voltage, Tape & Reel). (2) Product die revision letter is marked on top of the package as a suffix to the production date code (e.g. AYWWB). For additional information, please contact your Catalyst sales office. 9 Doc. No. 1031, Rev. F REVISION HISTORY Date Revision Comments 02/03/2004 C Added: CAT24WC256 not recommended for new designs. See CAT24FC256 data sheet. 04/18/04 D Delete data sheet designation Update Features Update Ordering Information 07/23/04 E Add die revision to Ordering Information 08/05/04 F Update DC Operating Characteristics table and notes Copyrights, Trademarks and Patents Trademarks and registered trademarks of Catalyst Semiconductor include each of the following: DPP ™ AE2 ™ Catalyst Semiconductor has been issued U.S. and foreign patents and has patent applications pending that protect its products. For a complete list of patents issued to Catalyst Semiconductor contact the Company’s corporate office at 408.542.1000. CATALYST SEMICONDUCTOR MAKES NO WARRANTY, REPRESENTATION OR GUARANTEE, EXPRESS OR IMPLIED, REGARDING THE SUITABILITY OF ITS PRODUCTS FOR ANY PARTICULAR PURPOSE, NOR THAT THE USE OF ITS PRODUCTS WILL NOT INFRINGE ITS INTELLECTUAL PROPERTY RIGHTS OR THE RIGHTS OF THIRD PARTIES WITH RESPECT TO ANY PARTICULAR USE OR APPLICATION AND SPECIFICALLY DISCLAIMS ANY AND ALL LIABILITY ARISING OUT OF ANY SUCH USE OR APPLICATION, INCLUDING BUT NOT LIMITED TO, CONSEQUENTIAL OR INCIDENTAL DAMAGES. Catalyst Semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Catalyst Semiconductor product could create a situation where personal injury or death may occur. Catalyst Semiconductor reserves the right to make changes to or discontinue any product or service described herein without notice. Products with data sheets labeled "Advance Information" or "Preliminary" and other products described herein may not be in production or offered for sale. Catalyst Semiconductor advises customers to obtain the current version of the relevant product information before placing orders. Circuit diagrams illustrate typical semiconductor applications and may not be complete. Catalyst Semiconductor, Inc. Corporate Headquarters 1250 Borregas Avenue Sunnyvale, CA 94089 Phone: 408.542.1000 Fax: 408.542.1200 www.catalyst-semiconductor.com Publication #: Revison: Issue date: 1031 F 08/05/04