NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI™) Synchronous Bus) General Description by the Status Register and is described in greater detail within this datasheet. In order to prevent spurious programming, the EEPROM has both a Write Enable command, which is immediately disabled after each programming operation, and a Write Protect (WP) pin, which must be pulled HIGH to program. The NM25C041 is a 4096-bit MODE 1 SPI (Serial Peripheral Interface) CMOS EEPROM which is designed for high-reliability non-volatile data storage applications. The SPI interface features a byte-wide format (all data is transferred in 8-bit words) to interface with the Motorola 68HC11 microprocessor, or equivalent, at a 2.1MHz clock transfer rate. (This interface is considered the fastest serial communication method.) This 4-wire SPI interface allows the end user full EEPROM functionality while keeping pin count and space requirements low for maximum PC board space utilization. Features ■ 2.1 MHz clock rate @ 2.7V to 5.5V ■ 4096 bits organized as 512 x 8 ■ Multiple chips on the same 3 wire bus with separate chip select lines ■ Self-timed programming cycle The SPI interface requires four I/O pins on each EEPROM device: Chip Select (CS), Clock (SCK), Serial Data In (SI), and Serial Data Out (SO), as well as 2 other control pins: Write Protect (WP) and HOLD (HOLD). The Write Protect pin can be used to disable the Write operation and the HOLD pin is used to interrupt the SI datastream and place the device in a Hold state during microprocessor instruction generation. Please refer to the following diagrams and description for more details. ■ Simultaneous programming of 1 to 4 bytes at a time ■ Status register can be polled during programming to monitor RDY/BUSY ■ Both the Write Protect (WP) pin and 'auto-write disable after programming' provides hardware and software write protection ■ Block write protect feature to protect against accidental writes All programming cycles are completely self-timed and do not require an ERASE, or similar setup, before programming any cells. Programming can be performed in 3 modes, address (byte) write, page (4 addresses/bytes) write or partial page write. Furthermore, the EEPROM is provided with 4 levels of write protection wherein the data, once programmed, cannot be altered. This is controlled ■ Endurance: 1,000,000 data changes ■ Data retention greater than 40 years ■ Packages available: 8-pin DIP and 8-pin SO Block Diagram CS HOLD SCK SI Instruction Register Program Enable Address Counter/ Register VPP Decoder 1 of 512 VCC VSS Instruction Decoder Control Logic and Clock Generators WP High Voltage Generator and Program Timer EEPROM Array 4096 Bits (512 x 8) Read/Write Amps Data In/Out Register 8 Bits Data Out Buffer SO Non-Volatile Status Register SPI™ is a trademark of Motorola Corporation. DS800002-1 © 1999 Fairchild Semiconductor Corporation NM25C041 Rev. D.1 1 www.fairchildsemi.com NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) March 1999 Pin Names Dual-In-Line Package (N) and SO Package (M8) CS 1 8 CS Chip Select Input SO Serial Data Output VCC WP Write Protect VSS Ground SO 2 7 HOLD WP 3 6 SCK SI VSS 4 5 Serial Data Input SCK Serial Clock Input HOLD SI Suspends Serial Data VCC Power Supply DS800002-2 Top View Ordering Information NM 25 C XX LZ E XX Letter Description N M8 8-pin DIP 8-pin SO Temp. Range None V E 0 to 70°C -40 to +125°C -40 to +85°C Voltage Operating Range Blank L LZ 4.5V to 5.5V 2.7V to 4.5V 2.7V to 4.5V and <1µA Standby Current 041 4K, mode 1 C CMOS Package Density/Mode Interface 2 NM25C041 Rev. D.1 25 SPI NM Fairchild Non-Volatile Memory www.fairchildsemi.com NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Connection Diagram Operating Conditions Ambient Storage Temperature Ambient Operating Temperature NM25C041 NM25C041E NM25C041V -65°C to +150°C All Input or Output Voltages with Respect to Ground +6.5V to -0.3V Lead Temperature (Soldering, 10 sec.) +300°C ESD Rating 0°C to +70°C -40°C to +85°C -40°C to +125°C Power Supply (VCC) NM25C041 2000V 4.5V to 5.5V DC and AC Electrical Characteristics 4.5V ≤ VCC ≤ 5.5V Symbol Parameter ICC Conditions Min Max Units Operating Current CS = VIL 3 mA Standby Current CS = VCC 50 µA IIL Input Leakage VIN = 0 to VCC -1 1 µA IOL Output Leakage VOUT = GND to VCC -1 1 µA ICCSB VIL Input Low Voltage -0.3 VCC * 0.3 V VIH Input High Voltage 0.7 * VCC VCC + 0.3 V VOL Output Low Voltage IOL = 1.6 mA 0.4 V VOH Output High Voltage IOH = -0.8 mA fOP SCK Frequency 2.1 MHz tRI Input Rise Time 2.0 µs tFI Input Fall Time 2.0 µs VCC - 0.8 V tCLH Clock High Time (Note 2) 190 ns tCLL Clock Low Time (Note 2) 190 ns tCSH Min CS High Time (Note 3) 240 ns tCSS CS Setup Time 240 ns tDIS Data Setup Time 100 ns tHDS HOLD Setup Time 90 ns tCSN CS Hold Time 240 ns tDIN Data Hold Time 100 ns tHDN HOLD Hold Time 90 ns tPD Output Delay tDH Output Hold Time tLZ HOLD to Output Low Z tDF Output Disable Time tHZ HOLD to Output High Z tWP Write Cycle Time CL = 200 pF 240 ns 100 ns 240 ns 100 ns 10 ms 0 CL = 200 pF 1–4 Bytes Capacitance (Note 4) TA = 25°C, f = 2.1/1 MHz Symbol Test Typ Max Units COUT Output Capacitance 3 8 pF CIN Input Capacitance 2 6 pF ns AC Test Conditions Output Load CL = 200 pF Input Pulse Levels 0.1 * VCC - 0.9 * VCC Timing Measurement Reference Level 0.3 * VCC - 0.7 * VCC Note 1: Stress above 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 the specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Note 2: The fOP frequency specification specifies a minimum clock period of 1/fOP. Therefore, for every fOP clock cycle, tCLH + tCLL must be equal to or greater than 1/fOP. For example, if the 2.1MHz period = 476ns and tCLH = 190ns, tCLL must be 286ns. Note 3: CS must be brought high for a minimum of tCSH between consecutive instruction cycles. Note 4: This parameter is periodically sampled and not 100% tested. 3 NM25C041 Rev. D.1 www.fairchildsemi.com NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Absolute Maximum Ratings (Note 1) Ambient Storage Temperature Ambient Operating Temperature NM25C041L/LZ NM25C041LE/LZE NM25C041LV -65°C to +150°C All Input or Output Voltage with Respect to Ground +6.5V to -0.3V Lead Temp. (Soldering, 10 sec.) +300°C ESD Rating 0°C to +70°C -40°C to +85°C -40°C to +125°C Power Supply (VCC) 2.7V - 4.5V 2000V DC and AC Electrical Characteristics 2.7V ≤ VCC ≤ 4.5V Symbol Parameter 25C041L/LE 25C041LZ/LZE Min. Max. Conditions 25C041LV Min 3 Max Units 3 mA ICC Operating Current CS = VIL ICCSB Standby Current L LZ CS = VCC IIL Input Leakage VIN = 0 to VCC -1 1 -1 1 µA IOL Output Leakage VOUT = GND to VCC -1 1 -1 1 µA VIL Input Low Voltage -0.3 VCC * 0.3 -0.3 VCC * 0.3 V VIH Input High Voltage 0.7 * VCC VCC + 0.3 0.7 * VCC VCC + 0.3 V VOL Output Low Voltage IOL = 0.8 mA VOH Output High Voltage IOH = –0.8 mA fOP SCK Frequency tRI tFI tCLH Clock High Time (Note 6) 410 410 ns tCLL Clock Low Time (Note 6) 410 410 ns tCSH Min. CS High Time (Note 7) 500 500 ns tCSS CS Setup Time 500 500 ns tDIS Data Setup Time 100 100 ns tHDS HOLD Setup Time 240 240 ns tCSN CS Hold Time 500 500 ns tDIN Data Hold Time 100 100 ns tHDN HOLD Hold Time 240 tPD Output Delay tDH Output Hold Time tLZ HOLD Output Low Z tDF Output Disable Time 500 500 ns tHZ HOLD to Output Hi Z 240 240 ns tWP Write Cycle Time 15 15 ms µA 10 1 0.4 VCC - 0.8 0.4 VCC - 0.8 V V 1.0 1.0 MHz Input Rise Time 2.0 2.0 µs Input Fall Time 2.0 2.0 µs 240 500 0 1-4 Bytes Symbol Test COUT Output Capacitance 3 8 pF Input Capacitance 2 6 pF ns 500 ns 240 ns 0 240 Capacitance TA = 25°C, f = 2.1/1 MHz (Note 8) CIN 10 N/A ns AC Test Conditions Output Load Typ Max Units CL = 200 pF Input Pulse Levels 0.1 * VCC - 0.9 * VCC Timing Measurement Reference Level 0.3 * VCC - 0.7 * VCC Note 5: Stress above 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 the specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Note 6 : The fOP frequency specification specifies a minimum clock period of 1/fOP. Therefore, for every fOP clock cycle, tCLH + tCLL must be equal to or greater than 1/fOP. For example, if the 2.1MHz period = 476ns and tCLH = 190ns, tCLL must be 286ns. Note 7: CS must be brought high for a minimum of tCSH between consecutive instruction cycles. Note 8: This parameter is periodically sampled and not 100% tested. 4 NM25C041 Rev. D.1 www.fairchildsemi.com NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Low Voltage 2.7V ≤ VCC ≤ 4.5V Specifications Operating Conditions Absolute Maximum Ratings (Note 5) FIGURE 1. Synchronous Data Timing tCSH VIH CS VIL VIH SCK tCSS tCSN tCLH VIL tDIS tCLL tDIN VIH SI VIL tPD tPD tDF VOH SO HI-Z HI-Z VOL DS800002-4 FIGURE 2. HOLD Timing SCK tHDS tHDN tHDS tHDN HOLD tHZ tLZ SO DS800002-6 5 NM25C041 Rev. D.1 www.fairchildsemi.com NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) , ,, AC Test Conditions (Continued) As an additional protection against data corruption, the device is designed so that, if an invalid opcode is received, the device will not shift any further data into the SI latches and SO will remain tristated. In this case, CS must again be brought HIGH to re-initialize the device and a new opcode re-entered. See Figure 4. TABLE 1. Op Codes Table Instruction Instruction Name Opcode Operation WREN 0000 0110 Set Write Enable Latch WRDI 0000 0100 Reset Write Enable Latch RDSR 0000 0101 Read Status Register WRSR 0000 0001 Write Status Register READ 0000 A011 Read Data from Memory Array ,,,,, FIGURE 4. Invalid Op-Code CS WRITE 0000 A010 NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Functional Description INVALID OP-CODE SI SO DS800002-7 Write Data to Memory Array READ STATUS REGISTER (RDSR): The Read Status Register (RDSR) instruction provides access to the status register which is used to interrogate the READY/BUSY and WRITE ENABLE status of the chip. Two non-volatile status register bits are used to select one of four levels of BLOCK WRITE PROTECTION. The status register format is shown in Table 2. Note: As the NM25C040 requires 9 address bits (4,096 ÷ 8 = 512 bytes = 29), the 9th bit (for R/W instructions) is inputted in the Instruction Set Byte in bit I3. This convention only applies to 4K SPI protocol. The NM25C041 SPI device uses a CS functionality, so the device is selected when CS is LOW (CS is to be held HIGH during 'standby' periods and between instruction sets). As stated above, the SPI protocol defines this as a MODE 1 part, with a CLOCK PHASE 1 and CLOCK POLARITY 0. This means that the part is active with CS = 0 (VIL), all INPUT data is latched into the device on the RISING edge of SCK and all OUTPUT data is clocked out on the FALLING edge of SCK. READ SEQUENCE: Reading the memory via the SPI link requires the following sequence. The CS line is pulled low to select the device. The READ op-code (which includes A8) is transmitted on the SI line followed by the byte address (A7–A0) to be read. After this is done, data on the SI line becomes don’t care. The data (D7–D0) at the address specified is then shifted out on the SO line. If only one byte is to be read, the CS line can be pulled back to the high level. It is possible to continue the READ sequence as the byte address is automatically incremented and data will continue to be shifted out. When the highest address is reached (1FF), the address counter rolls over to lowest address (000) allowing the entire memory to be read in one continuous READ cycle. See Figure 5. ,, ,, ,, ,, ,,,,,, FIGURE 3. SPI Protocol CS … SCK SI Bit 7 Bit 6 SO Bit 7 Bit 6 … … Bit 1 Bit 0 Bit 1 Bit 0 FIGURE 5. Read Sequence DS800002-5 CS The HOLD pin operation is used when the device is selected (CS LOW) and the application requires that the SI datastream be stopped and then restarted. The HOLD pin allows a fully 'static' operation, wherin the device may be put on HOLD by bringing the HOLD pin LOW (VIL). During the HOLD state, SCK must be HIGH and CS must remain LOW (device selected). In order to resume EEPROM serial communication, HOLD must be again brought HIGH and the SCK/SI signals resumed. During the HOLD state, SO is tri-stated (high impedance). SI SO BYTE ADDR (n) DATA (n) DATA (n+1) DATA (n+2) DATA (n+3) DS800002-8 6 NM25C041 Rev. D.1 READ OP-CODE www.fairchildsemi.com WRITE DISABLE (WRDI): To protect against accidental data disturbance the WRITE DISABLE (WRDI) instruction disables all programming modes. The WRITE DISABLE instruction is independent of the status of the WP pin. See Figure 8. TABLE 2. Status Register Format Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 X X X X BP1 BP0 WEN RDY ,,,,, FIGURE 8. Write Disable X = Don't Care CS Status register Bit 0 = 0 (RDY) indicates that the device is READY; Bit 0 = 1 indicates that a program cycle is in progress. Bit 1 = 0 (WEN) indicates that the device is not WRITE ENABLED; Bit 1 = 1 indicates that the device is WRITE ENABLED. Non-volatile status register Bits 2 and 3 (BP0 and BP1) indicate the level of BLOCK WRITE PROTECTION selected. The block write protection levels and corresponding status register control bits are shown in Table 3. Note that if a RDSR instruction is executed during a programming cycle only the RDY bit is valid. All other bits are 1s. See Figure 6. SI Status Register Bits BP0 0 0 0 None 1 0 1 180–1FF 2 1 0 100–1FF DS800002-11 WRITE SEQUENCE: To program the device the WRITE PROTECT (WP) pin must be held high and two separate instructions must be executed. The chip must first be write enabled via the WRITE ENABLE instruction and then a WRITE instruction must be executed. Moreover, the address of the memory location(s) to be programmed must be outside the protected address field selected by the Block Write Protection Level. See Table 3. Array Address Protected BP1 WRDI OP-CODE SO TABLE 3. Block Write Protection Levels Level NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Functional Description (Continued) A WRITE command requires the following sequence. The CS line is pulled low to select the device, then the WRITE op-code (which includes A8) is transmitted on the SI line followed by the byte address (A7–A0) and the corresponding pro-data (D7–D0) to be programmed. Programming will start after the CS pin is forced back to a high level. Note that the LOW to HIGH transition of the CS pin must occur during the SCK low time immediately after clocking in the D0 data bit. The READY/BUSY status of the device can be determined by executing a READ STATUS REGISTER (RDSR) instruction. Bit 0 = 1 indicates that the WRITE cycle is still in progress and Bit 0 = 0 indicates that the WRITE cycle has ended. During the WRITE programming cycle (Bit 0 = 1) only the READ STATUS REGISTER instruction is enabled. ,,,,,, ,,,,, ,, 3 1 1 000–1FF FIGURE 6. Read Status CS SI RDSR OP-CODE FIGURE 9. Start WRITE Condition CS SO SR_DATA MSB...LSB SCK DS800002-9 SI WRITE ENABLE (WREN): When VCC is applied to the chip, it “powers up” in the write disable state. Therefore, all modes must be preceded by a WRITE ENABLE (WREN) instruction. Additionally the WP pin must be held high during a WRITE ENABLE instruction. At the completion of a WRITE or WRSR cycle the device is automatically turned to the write disable state. Note that a WRITE DISABLE (WRDI) instruction or forcing the WP pin low will also return the device to the write disable state. See Figure 7. SO ,,,,, ,,,,,, D2 D1 D0 DS800002-12 FIGURE 7. Write Enable CS SI SO WREN OP-CODE DS800002-10 7 NM25C041 Rev. D.1 www.fairchildsemi.com The NM25C041 is capable of a four byte PAGE WRITE operation. After receipt of each byte of data the two low order address bits are internally incremented by one. The seven high order bits of the address will remain constant. If the master should transmit more than four bytes of data, the address counter will “roll over”, and the previously loaded data will be reloaded. See Figure 10. Note that the first four bits are don’t care bits followed by BP1 and BP0 then two additional don’t care bits. Programming will start after the CS pin is forced back to a high level. As in the WRITE instruction the LOW to HIGH transition of the CS pin must occur during the SCK low time immediately after clocking in the last don’t care bit. See Figure 12. FIGURE 10. 4 Page Byte Write FIGURE 12. Start WRSR Condition CS ,,,,,,,,,,,,, ,, CS tCSN SI WRITE OP-CODE BYTE ADDR(n) DATA (n) DATA (n+1) DATA (n+2) DATA (n+3) SCK ,,,,,, tDIS SO NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Functional Description (Continued) SI DS800002-13 At the completion of a WRITE cycle the device is automatically returned to the write disable state. SO tDIN BP0 DS800002-15 The READY/BUSY status of the device can be determined by executing a READ STATUS REGISTER (RDSR) instruction. Bit 0 = 1 indicates that the WRSR cycle is still in progress and Bit 0 = 0 indicates that the WRSR cycle has ended. If the WP pin is forced low or the device is not WRITE enabled, the device will ignore the WRITE instruction and return to the standby state when CS is forced high. A new CS falling edge is required to re-initialize the serial communication. At the completion of a WRSR cycle the device is automatically returned to the write disable state. WRITE STATUS REGISTER (WRSR): The WRITE STATUS REGISTER (WRSR) instruction is used to program the nonvolatile status register Bits 2 and 3 (BP0 and BP1). As in the WRITE mode the WRITE PROTECT (WP) pin must be held high and two separate instructions must be executed. The chip must first be write enabled via the WRITE ENABLE instruction and then a WRSR instruction must be executed. The WRSR command requires the following sequence. The CS line is pulled low to select the device and then the WRSR op-code is transmitted on the SI line followed by the data to be programmed (see Figure 11). ,,,,,,, FIGURE 11. Write Status Register CS SI WRSR OP-CODE SR_DATA XXXXBP1BP0XX SO DS800002-14 8 NM25C041 Rev. D.1 www.fairchildsemi.com NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Physical Dimensions inches (millimeters) unless otherwise noted 0.189 - 0.197 (4.800 - 5.004) 8 7 6 5 0.228 - 0.244 (5.791 - 6.198) 1 2 3 4 Lead #1 IDENT 0.010 - 0.020 x 45° (0.254 - 0.508) 0.0075 - 0.0098 (0.190 - 0.249) Typ. All Leads 0.150 - 0.157 (3.810 - 3.988) 0.053 - 0.069 (1.346 - 1.753) 8° Max, Typ. All leads 0.04 (0.102) All lead tips 0.004 - 0.010 (0.102 - 0.254) Seating Plane 0.014 (0.356) 0.016 - 0.050 (0.406 - 1.270) Typ. All Leads 0.050 (1.270) Typ 0.014 - 0.020 Typ. (0.356 - 0.508) Molded Small Out-Line Package (M8) Order Number NM25C041M8 Package Number M08A 9 NM25C041 Rev. D.1 www.fairchildsemi.com 0.373 - 0.400 (9.474 - 10.16) 0.090 (2.286) 8 0.092 DIA (2.337) 7 6 0.250 - 0.005 (6.35 ± 0.127) + Pin #1 IDENT 0.032 ± 0.005 (0.813 ± 0.127) RAD 5 8 Pin #1 IDENT 1 Option 1 1 0.280 MIN (7.112) 0.300 - 0.320 (7.62 - 8.128) 7 2 0.040 Typ. (1.016) 0.030 MAX (0.762) 20° ± 1° 3 4 Option 2 0.145 - 0.200 (3.683 - 5.080) 0.039 (0.991) 0.130 ± 0.005 (3.302 ± 0.127) 95° ± 5° 0.009 - 0.015 (0.229 - 0.381) +0.040 0.325 -0.015 +1.016 8.255 -0.381 0.125 (3.175) DIA NOM 0.125 - 0.140 (3.175 - 3.556) 0.065 (1.651) 90° ± 4° Typ 0.018 ± 0.003 (0.457 ± 0.076) 0.100 ± 0.010 (2.540 ± 0.254) 0.045 ± 0.015 (1.143 ± 0.381) 0.020 (0.508) Min 0.060 (1.524) 0.050 (1.270) Molded Dual-In-Line Package (N) Order Number NM25C041N Package Number N08E Life Support Policy Fairchild's products are not authorized for use as critical components in life support devices or systems without the express written approval of the President of Fairchild Semiconductor Corporation. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. Fairchild Semiconductor Americas Customer Response Center Tel. 1-888-522-5372 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. Fairchild Semiconductor Europe Fax: +44 (0) 1793-856858 Deutsch Tel: +49 (0) 8141-6102-0 English Tel: +44 (0) 1793-856856 Français Tel: +33 (0) 1-6930-3696 Italiano Tel: +39 (0) 2-249111-1 Fairchild Semiconductor Hong Kong 8/F, Room 808, Empire Centre 68 Mody Road, Tsimshatsui East Kowloon. Hong Kong Tel; +852-2722-8338 Fax: +852-2722-8383 Fairchild Semiconductor Japan Ltd. 4F, Natsume Bldg. 2-18-6, Yushima, Bunkyo-ku Tokyo, 113-0034 Japan Tel: 81-3-3818-8840 Fax: 81-3-3818-8841 Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and Fairchild reserves the right at any time without notice to change said circuitry and specifications. 10 NM25C041 Rev. D.1 www.fairchildsemi.com NM25C041 4K-Bit Serial Interface CMOS EEPROM (Serial Peripheral Interface (SPI) Synchronous Bus) Physical Dimensions inches (millimeters) unless otherwise noted