Features • • • • • • • • • • Serial Peripheral Interface (SPI) Compatible Supports SPI Modes 0 (0,0) and 3 (1,1) 2.1 MHz Clock Rate 128-Byte Page Mode Only for Write Operations Low Voltage and Standard Voltage Operation – 5.0 (VCC = 4.5V to 5.5V) – 2.7 (VCC = 2.7V to 5.5V) – 1.8 (VCC = 1.8V to 3.6V) Block Write Protection – Protect 1/4, 1/2, or Entire Array Write Protect (WP) Pin and Write Disable Instructions for Both Hardware and Software Data Protection Self-Timed Write Cycle (5 ms Typical) High Reliability – Endurance: 100,000 Write Cycles – Data Retention: >40 Years – ESD Protection: >3000V 20-Pin JEDEC SOIC and 8-Pin Leadless Array Package SPI Serial EEPROMs 1M (131,072 x 8) Description The AT25P1024 provides 1,048,576 bits of serial electrically erasable programmable read only memory (EEPROM) organized as 131,072 words of 8 bits each. The device is optimized for use in many industrial and commercial applications where low power and low voltage operation are essential. The AT25P1024 is available in space saving 20-pin JEDEC SOIC and 8-pin leadless array (LAP) packages. AT25P1024 Preliminary (continued) Pin Configurations Pin Name Function CS Chip Select SCK Serial Data Clock SI Serial Data Input SO Serial Data Output GND Ground VCC Power Supply WP Write Protect HOLD Suspends Serial Input NC No Connect 20-Lead SOIC CS SO NC NC NC NC NC NC WP GND 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 VCC HOLD NC NC NC NC NC NC SCK SI 8-Pin LAP VCC HOLD SCK SI 8 7 6 5 1 2 3 4 CS SO WP GND Bottom View Rev. 1082C–08/98 1 The AT25P1024 is enabled through the Chip Select pin (CS) and accessed via a 3-wire interface consisting of Serial Data Input (SI), Serial Data Output (SO), and Serial Clock (SCK). All programming cycles are completely selftimed, and no separate ERASE cycle is required before WRITE. BLOCK WRITE protection is enabled by programming the status register with top ¼, top ½ or entire array of write protection. Separate program enable and program disable instructions are provided for additional data protection. Hardware data protection is provided via the WP pin to protect against inadvertent write attempts to the status register. The HOLD pin may be used to suspend any serial communication without resetting the serial sequence. Absolute Maximum Ratings* Operating Temperature .................................. -55°C to +125°C Storage Temperature ..................................... -65°C to +150°C Voltage on Any Pin with Respect to Ground .................................... -1.0V to +7.0V Maximum Operating Voltage........................................... 6.25V DC Output Current ........................................................ 5.0 mA *NOTICE: Block Diagram 131,072 x 8 2 AT25P1024 Stresses beyond 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 beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. AT25P1024 Pin Capacitance(1) Applicable over recommended operating range from TA = 25°C, f = 1.0 MHz, VCC = +5.0V (unless otherwise noted). Test Conditions COUT CIN Note: Max Units Conditions 8 pF VOUT = 0V 6 pF VIN = 0V Output Capacitance (SO) Input Capacitance (CS, SCK, SI, WP, HOLD) 1. This parameter is characterized and is not 100% tested. DC Characteristics Applicable over recommended operating range from: TAI = -40°C to +85°C, VCC = +1.8V to +5.5V, TAC = 0°C to +70°C, VCC = +1.8V to +5.5V (unless otherwise noted). Symbol Parameter VCC1 Supply Voltage VCC2 Max Units 1.8 3.6 V Supply Voltage 2.7 5.5 V VCC3 Supply Voltage 4.5 5.5 V ICC1 Supply Current VCC = 5.0V at 1 MHz, SO = Open Read 2.0 5.0 mA ICC2 Supply Current VCC = 5.0V at 2 MHz, SO = Open Write 4.0 7.0 mA ISB1 Standby Current VCC = 1.8V, CS = VCC 0.1 3.0 µA ISB2 Standby Current VCC = 2.7V, CS = VCC 0.2 3.0 µA ISB3 Standby Current VCC = 5.0V, CS = VCC 2.0 7.0 µA IIL Input Leakage VIN = 0V to VCC -3.0 3.0 µA IOL Output Leakage VIN = 0V to VCC, TAC = 0°C to 70°C -3.0 3.0 µA Input Low Voltage -0.6 VCC x 0.3 V Input High Voltage VCC x 0.7 VCC + 0.5 V 0.4 V VIL(1) VIH (1) VOL1 Output Low Voltage VOH1 Output High Voltage VOL2 Output Low Voltage VOH2 Output High Voltage Note: Test Condition 4.5V ≤ VCC ≤ 5.5V 1.8V ≤ VCC ≤ 3.6V Min IOL = 3.0 mA IOH = -1.6 mA VCC - 0.8 IOL = 0.15 mA IOH = -100 µA Typ V 0.2 VCC - 0.2 V V 1. VIL and VIH max are reference only and are not tested. 3 AC Characteristics Applicable over recommended operating range from TA = -40°C to +85°C, VCC = As Specified, CL = 1 TTL Gate and 100 pF (unless otherwise noted). Symbol Parameter Voltage Min Max Units fSCK SCK Clock Frequency 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 0 0 0 2.1 1.0 0.5 MHz tRI Input Rise Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 2 2 2 µs tFI Input Fall Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 2 2 2 µs tWH SCK High Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 200 400 800 ns tWL SCK Low Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 200 400 800 ns tCS CS High Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 250 500 1000 ns tCSS CS Setup Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 100 250 1000 ns tCSH CS Hold Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 150 250 1000 ns tSU Data In Setup Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 30 50 100 ns tH Data In Hold Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 50 50 100 ns tHD Hold Setup Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 100 100 400 ns tCD Hold Hold Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 200 300 400 ns tV Output Valid 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 0 0 0 tHO Output Hold Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 0 0 0 4 AT25P1024 200 400 800 ns ns AT25P1024 AC Characteristics (Continued) Applicable over recommended operating range from TA = -40°C to +85°C, VCC = As Specified, CL = 1 TTL Gate and 100 pF (unless otherwise noted). Symbol Parameter Voltage Min Max Units tLZ Hold to Output Low Z 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 0 0 0 100 200 300 ns tHZ Hold to Output High Z 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 100 200 300 ns tDIS Output Disable Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 200 250 1000 ns tWC Write Cycle Time 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 5 10 10 ms Endurance(1) 5.0V, 25°C, Page Mode 4.5 - 5.5 2.7 - 5.5 1.8 - 3.6 Note: 100K Write Cycles 1. This parameter is characterized and is not 100% tested. 5 Serial Interface Description MASTER: The device that generates the serial clock. SLAVE: Because the Serial Clock pin (SCK) is always an input, the AT25P1024 always operates as a slave. TRANSMITTER/RE CEIV ER: The AT25P 1024 has separate pins designated for data transmission (SO) and reception (SI). MSB: The Most Significant Bit (MSB) is the first bit transmitted and received. SERIAL OP-CODE: After the device is selected with CS going low, the first byte will be received. This byte contains the op-code that defines the operations to be performed. INVALID OP-CODE: If an invalid op-code is received, no data will be shifted into the AT25P1024, and the serial output pin (SO) will remain in a high impedance state until the falling edge of CS is detected again. This will reinitialize the serial communication. CHIP SELECT: The AT25P1024 is selected when the CS pin is low. When the device is not selected, data will not be accepted via the SI pin, and the serial output pin (SO) will remain in a high impedance state. HOLD: The HOLD pin is used in conjunction with the CS pin to select the AT25P1024. When the device is selected and a serial sequence is underway, HOLD can be used to pause the serial communication with the master device without resetting the serial sequence. To pause, the HOLD pin must be brought low while the SCK pin is low. To resume serial communication, the HOLD pin is brought high while the SCK pin is low (SCK may still toggle during HOLD). Inputs to the SI pin will be ignored while the SO pin is in the high impedance state. WRITE PROTECT: The write protect pin (WP) will allow normal read/write operations when held high. When the WP pin is brought low and WPEN bit is “1”, all write operations to the status register are inhibited. WP going low while CS is still low will interrupt a write to the status register. If the internal write cycle has already been initiated, WP going low will have no effect on any write operation to the 6 AT25P1024 status register. The WP pin function is blocked when the WPEN bit in the status register is “0”. This will allow the user to install the AT25P1024 in a system with the WP pin tied to ground and still be able to write to the status register. All WP pin functions are enabled when the WPEN bit is set to “1”. SPI Serial Interface MASTER: MICROCONTROLLER DATA OUT (MOSI) DATA IN (MISO) SERIAL CLOCK (SPI CK) SS0 SS1 SS2 SS3 SLAVE: AT25P1024 SI SO SCK CS SI SO SCK CS SI SO SCK CS SI SO SCK CS AT25P1024 Functional Description The AT25P1024 is designed to interface directly with the synchronous serial peripheral interface (SPI) of the 6800 type series of microcontrollers. The AT25P1024 utilizes an 8-bit instruction register. The list of instructions and their operation codes are contained in Table 1. All instructions, addresses, and data are transferred with the MSB first and start with a high-to-low transition. Table 3. Read Status Register Bit Definition Bit Definition Bit 0 (RDY) Bit 0 = 0 (RDY) indicates the device is READY. Bit 0 = 1 indicates the write cycle is in progress. Bit 1 (WEN) Bit 1= 0 indicates the device is not WRITE ENABLED. Bit 1 = 1 indicates the device is WRITE ENABLED. Bit 2 (BP0) See Table 4. See Table 4. Table 1. Instruction Set for the AT25P1024 Instruction Name Instruction Format Operation Bit 3 (BP1) WREN 0000 X110 Set Write Enable Latch Bits 4-6 are 0s when device is not in an internal write cycle. WRDI 0000 X100 Reset Write Enable Latch Bit 7 (WPEN) RDSR 0000 X101 Read Status Register Bits 0-7 are 1s during an internal write cycle. WRSR 0000 X001 Write Status Register READ 0000 X011 Read Data from Memory Array WRITE 0000 X010 Write Data to Memory Array WRITE ENABLE (WREN): The device will power up in the write disable state when VCC is applied. All programming instructions must therefore be preceded by a Write Enable instruction. WRITE DISABLE (WRDI): To protect the device against inadvertent writes, the Write Disable instruction disables all programming modes. The WRDI instruction is independent of the status of the WP pin. READ STATUS REGISTER (RDSR): The Read Status Register instruction provides access to the status register. The READY/BUSY and Write Enable status of the device can be determined by the RDSR instruction. Similarly, the Block Write Protection bits indicate the extent of protection employed. These bits are set by using the WRSR instruction. Table 2. Status Register Format Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 WPEN X X X BP1 BP0 WEN RDY See Table 5. WRITE STATUS REGISTER (WRSR): The WRSR instruction allows the user to select one of four levels of protection. The AT25P1024 is divided into four array segments. Top quarter (1/4), top half (1/2), or all of the memory segments can be protected. Any of the data within any selected segment will therefore be READ only. The block write protection levels and corresponding status register control bits are shown in Table 4. The three bits, BP0, BP1, and WPEN are nonvolatile cells that have the same properties and functions as the regular memory cells (e.g. WREN, tWC, RDSR). Table 4. Block Write Protect Bits Status Register Bits Level Array Addresses Protected BP1 BP0 AT25P1024 0 0 0 None 1(1/4) 0 1 01800 - 01FFFF 2(1/2) 1 0 010000 - 01FFFF 3(All) 1 1 0000 - 01FFFF The WRSR instruction also allows the user to enable or disable the write protect (WP) pin through the use of the Write Protect Enable (WPEN) bit. Hardware write protection is enabled when the WP pin is low and the WPEN bit is “1”. Hardware write protection is disabled when either the WP pin is high or the WPEN bit is “0.” When the device is hardware write protected, writes to the Status Register, including the Block Protect bits and the WPEN bit, and the block-protected sections in the memory array are disabled. 7 Writes are only allowed to sections of the memory which are not block-protected. Note: When the WPEN bit is hardware write protected, it cannot be changed back to “0”, as long as the WP pin is held low. Table 5. WPEN Operation WPEN WP WEN Protected Blocks Unprotected Blocks Status Register 0 X 0 Protected Protected Protected 0 X 1 Protected Writable Writable 1 Low 0 Protected Protected Protected 1 Low 1 Protected Writable Protected X High 0 Protected Protected Protected X High 1 Protected Writable Writable READ SEQUENCE (READ): Reading the AT25P1024 via the SO (Serial Output) pin requires the following sequence. After the CS line is pulled low to select a device, the READ op-code is transmitted via the SI line followed by the byte address to be read (Refer to Table 6). Upon completion, any data on the SI line will be ignored. The data (D7-D0) at the specified address is then shifted out onto the SO line. If only one byte is to be read, the CS line should be driven high after the data comes out. The READ sequence can be continued since the byte address is automatically incremented and data will continue to be shifted out. When the highest address is reached, the address counter will roll over to the lowest address allowing the entire memory to be read in one continuous READ cycle. WRITE SEQUENCE (WRITE): In order to program the AT25P1024, two separate instructions must be executed. First, the device must be write enabled via the Write Enable (WREN) Instruction. Then a Write (WRITE) Instruction may be executed. Also, the address of the memory location(s) to be programmed must be outside the protected address field location selected by the Block Write 8 AT25P1024 Protection Level. During an internal write cycle, all commands will be ignored except the RDSR instruction. A Write Instruction requires the following sequence. After the CS line is pulled low to select the device, the WRITE op-code is transmitted via the SI line followed by the byte address and the data (D7-D0) to be programmed (Refer to Table 6). Programming will start after the CS pin is brought high. (The LOW to High transition of the CS pin must occur during the SCK low time immediately after clocking in the D0 (LSB) data bit. The READY/BUSY status of the device can be determined by initiating a READ STATUS REGISTER (RDSR) Instruction. If Bit 0 = 1, the WRITE cycle is still in progress. If Bit 0 = 0, the WRITE cycle has ended. Only the READ STATUS REGISTER instruction is enabled during the WRITE programming cycle. The AT25P1024 is capable of a 128-byte PAGE WRITE operation ONLY. Content of the page in the array will not be guaranteed if less than 128 bytes of data is received (byte operation is not supported). After each byte of data is received, the seven low order address bits are internally incremented by one; the high order bits of the address will remain constant. If more than 128 bytes of data are transmitted, the address counter will roll over and the previously written data will be overwritten. The AT25P1024 is automatically returned to the write disable state at the completion of a WRITE cycle. NOTE: If the device is not Write enabled (WREN), the device will ignore the Write instruction and will return to the standby state, when CS is brought high. A new CS falling edge is required to re-initiate the serial communication. Table 6. Address Key Address AT25P1024 AN A16 - A0 Don’t Care Bits A23 - A17 AT25P1024 Timing Diagrams (for SPI Mode 0 (0, 0)) Synchronous Data Timing t CS VIH CS VIL t CSH t CSS VIH t WH SCK t WL VIL tH t SU VIH SI VALID IN VIL tV VOH SO HI-Z t HO t DIS HI-Z VOL WREN Timing WRDI Timing 9 RDSR Timing CS 0 1 2 3 4 5 6 7 8 9 10 7 6 5 11 12 13 14 2 1 SCK INSTRUCTION SI DATA OUT HIGH IMPEDANCE SO 4 3 0 MSB WRSR Timing READ Timing CS 0 1 2 3 4 5 6 7 8 9 10 11 28 29 30 31 32 33 34 35 36 37 38 SCK 3-BYTE ADDRESS SI SO 10 INSTRUCTION HIGH IMPEDANCE AT25P1024 23 22 21 ... 3 2 1 0 7 6 5 4 3 2 1 0 AT25P1024 WRITE Timing 4 5 6 7 8 9 10 11 28 29 30 31 32 33 34 1055 3 1054 2 1053 1 1052 0 1051 CS SCK 128th BYTE DATA-IN 1st BYTE DATA-IN 3-BYTE ADDRESS SI INSTRUCTION 23 22 21 3 2 1 0 7 6 5 4 3 2 1 0 HIGH IMPEDANCE SO HOLD Timing CS tCD tCD SCK tHD tHD HOLD tHZ SO tLZ 11 Ordering Information tWC (max) (ms) ICC (max) (µ µA) ISB (max) (µ µA) fMAX (kHz) 5 7000 7.0 7000 10 10 Ordering Code Package 2100 AT25P1024C1-10CC AT25P1024W1-10SC 8C1 20S Commercial (0°C to 70°C) 7.0 2100 AT25P1024C1-10CI AT25P1024W1-10SI 8C1 20S Industrial (-40°C to 85°C) 2000 3.0 1400 AT25P1024C1-10CC-2.7 AT25P1024W1-10SC-2.7 8C1 20S Commercial (0°C to 70°C) 2000 3.0 1000 AT25P1024C1-10CI-2.7 AT25P1024W1-10SI-2.7 8C1 20S Industrial (-40°C to 85°C) 1000 3.0 500 AT25P1024C1-10CC-1.8 AT25P1024W1-10SC-1.8 8C1 20S Commercial (0°C to 70°C) 1000 3.0 500 AT25P1024C1-10CI-1.8 AT25P1024W1-10SI-1.8 8C1 20S Industrial (-40°C to 85°C) Package Type 8C1 8-Lead, 0.300" Wide, Leadless Array Package (LAP) 20S 20-Lead, 0.300" Wide, Plastic Gull Wing Small Outline Package (JEDEC SOIC) Options Blank Standard Device (4.5V to 5.5V) -2.7 Low Voltage (2.7V to 5.5V) -1.8 Low Voltage (1.8V to 3.6V) 12 AT25P1024 Operation Range AT25P1024 Packaging Information 8C1, 8-Lead, 0.300" Wide, Leadless Array Package (LAP) Dimensions in Inches and (Millimeters) 20S, 20-Lead, 0.300" Wide, Plastic Gull Wing Small Outline (JEDEC SOIC) Dimensions in Inches and (Millimeters) 0.020 (0.508) 0.013 (0.330) SIDE VIEW TOP VIEW 0.299 (7.60) 0.420 (10.7) 0.291 (7.39) 0.393 (9.98) PIN 1 5.15 (0.203) 4.85 (0.191) .050 (1.27) BSC 8.15 (0.321) 7.85 (0.309) 1.30 (0.051) 1.00 (0.039) 0.42 (0.017) 0.34 (0.013) 0.513 (13.0) 0.497 (12.6) 0.105 (2.67) 0.092 (2.34) BOTTOM VIEW 8 1 7 2 6 3 5 4 0.012 (0.305) 0.003 (0.076) 0.41 (0.016) TYP 1.27 (0.050) TYP 0.64 (0.025) TYP 0 REF 8 0.013 (0.330) 0.009 (0.229) 0.035 (0.889) 0.015 (0.381) 13