ACE24C32/64B Two-wire Serial EEPROM Description The ACE24C32B/ACE24C64B provides 32,768/65,536 bits of serial electrically erasable and programmable read-only memory (EEPROM) organized as 4096/8192 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. Features Wide Voltage Operation - VCC = 1.7V to 5.5V Operating Ambient Temperature: -40℃ to +85℃ Internally Organized: ACE24C32B, 4096 * 8 (2K bits) / ACE24C64B, 8192 * 8 (4K bits) Two-wire Serial Interface Schmitt Trigger, Filtered Inputs for Noise Suppression Bidirectional Data Transfer Protocol 1 MHz (5V), 400 kHz (1.7V, 2.5V, 2.7V) Compatibility Write Protect Pin for Hardware Data Protection 32-byte Page (32K, 64K) Write Modes Partial Page Writes Allowed Self-timed Write Cycle (5 ms max) High-reliability - Endurance: 1 Million Write Cycles - Data Retention: 100 Years Absolute Maximum Ratings Operating Temperature -40℃ to 85℃ Storage Temperature -65℃ to 150℃ DC Supply Voltage 0.3V ot 6.5V Input / Output Voltage GND-0.3V ot VCC+0.3V Notice: Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to this device. These are stress ratings only. Functional operation of this device at these or any other conditions above those indicated in the operational sections of this specification is not implied or intended. Exposure to the absolute maximum rating conditions for extended periods may affect device reliability. VER 1.3 1 ACE24C32/64B Two-wire Serial EEPROM Packaging Type DIP-8 SOP-8 TSSOP-8 MSOP-8 TDFN Pin Configurations Pin Name Functions AO-A2 Address Inputs SDA Serial Data SCL Serial Clock Input WP Write Protect GND Ground VCC Power Supply Ordering information ACE24C32/64B XX + X H Halogen-free U : Tube T : Tape and Reel Pb - free DP : DIP-8 FM : SOP-8 TM : TSSOP-8 OM : MSOP-8 DM : TDFN VER 1.3 2 ACE24C32/64B Two-wire Serial EEPROM Block Diagram VER 1.3 3 ACE24C32/64B Two-wire Serial EEPROM Pin Descriptions Device/Page Addresses (A2, A1 and A0): The A2, A1 and A0 pins are device address inputs that are hard wired for the ACE24C32B/ACE24C64B. Eight 32K/64K devices may be addressed on a single bus system (device addressing is discussed in detail under the Device Addressing section). Serial Data (SDA): The SDA pin is bi-directional for serial data transfer. This pin is open-drain driven and may be wire-ORed with any number of other open-drain or open- collector devices. Serial Clock (SCL): The SCL input is used to positive edge clock data into each EEPROM device and negative edge clock data out of each device. Write Protect (WP): The ACE24C32B/ACE24C64B has a Write Protect pin that provides hardware data protection. The Write Protect pin allows normal read/write operations when connected to ground (GND). When the Write Protect pin is connected to VCC, the write protection feature is enabled and operates as shown in the following Table 2. WP Pin Status At VCC At GND Part of the Array Protected ACE24C32B ACE24C64B Full (32K) Array Full (256K) Array Normal Read / Write Operations Table 2 Write Protect Memory Organization ACE24C32B, 32K Serial EEPROM: Internally organized with 128 pages of 32 bytes each, the 32K requires an 12-bit data word address for random word address. ACE24C64B, 64K Serial EEPROM: Internally organized with 256 pages of 32 bytes each, the 64K requires an 13-bit data word address for random word address. Device Operation Clock and Data Transitions: The SDA pin is normally pulled high with an external device. Data on the SDA pin may change only during SCL low time periods (see to Figure 1). Data changes during SCL high periods will indicate a start or stop condition as defined below. Start Condition: A high-to-low transition of SDA with SCL high is a start condition which must precede any other command (see to Figure 2). Stop Condition: A low-to-high transition of SDA with SCL high is a stop condition. After a read sequence, the stop command will place the EEPROM in a standby power mode (see to Figure 2). VER 1.3 4 ACE24C32/64B Two-wire Serial EEPROM Acknowledge: All addresses and data words are serially transmitted to and from the EEPROM in 8-bit words. The EEPROM sends a zero to acknowledge that it has received each word. The happens during the ninth clock cycle. Standby Mode : The ACE24C32B/ACE24C64B features a low-power standby mode which is enabled: (a) upon power-up and (b) after the receipt of the stop bit and the completion of any internal operations. Memory Reset : After an interruption in protocol power loss or system reset, any two-wire part can be protocol reset by following these steps: 1. Clock up to 9 cycles. 2. Look for SDA high in each cycle while SCL is high and then. 3. Create a start condition. Figure 1: Data Validity Figure 2: Start and Stop Definition VER 1.3 5 ACE24C32/64B Two-wire Serial EEPROM Figure 3: Output Acknowledge Device Addressing The 32K, and 64K EEPROM devices all require an 8-bit device address word following a start condition to enable the chip for a read or write operation (see to Figure 4). The device address word consists of a mandatory “1”, “0” sequence for the first four most significant bits as shown. This is common to all the EEPROM devices. The next 3 bits are the A2, A1 and A0 device address bits for the 32K/64K EEPROM. These 3 bits must compare to their corresponding hard-wired input pins. The eighth bit of the device address is the read/write operation select bit. A read operation is initiated if this bit is high and a write operation is initiated if this bit is low. Upon a compare of the device address, the EEPROM will output a “0”. If a compare is not made, the chip will return to a standby state. Write Operations Byte Write: A write operation requires an 8-bit data word address following the device address word and acknowledgment. Upon receipt of this address, the EEPROM will again respond with a “0” and then clock in the first 8-bit data word. Following receipt of the 8-bit data word, the EEPROM will output a “0” and the addressing device, such as a microcontroller, must terminate the write sequence with a stop condition. At this time the EEPROM enters an internally timed write cycle, tWR, to the nonvolatile memory. All inputs are disabled during this write cycle and the EEPROM will not respond until the write is complete (see to Figure 5). VER 1.3 6 ACE24C32/64B Two-wire Serial EEPROM Page Write: The 32K/64K EEPROM is capable of an 32-byte page write. A page write is initiated the same as a byte write, but the microcontroller does not send a stop condition after the first data word is clocked in. Instead, after the EEPROM acknowledges receipt of the first data word, the microcontroller can transmit up to 31 (32K/64K) more data words. The EEPROM will respond with a “0” after each data word received. The microcontroller must terminate the page write sequence with a stop condition (see to Figure 6). The data word address lower three (32K/64K) bits are internally incremented following the receipt of each data word. The higher data word address bits are not incremented, retaining the memory page row location. When the word address, internally generated, reaches the page boundary, the following byte is placed at the beginning of the same page. If more than 32 (32K/64K) data words are transmitted to the EEPROM, the data word address will “roll over” and previous data will be overwritten. Acknowledge Polling: Once the internally timed write cycle has started and the EEPROM inputs are disabled, acknowledge polling can be initiated. This involves sending a start condition followed by the device address word. The read/write bit is representative of the operation desired. Only if the internal write cycle has completed will the EEPROM respond with a “0” allowing the read or write sequence to continue. Read Operations Read operations are initiated the same way as write operations with the exception that the read/write select bit in the device address word is set to “1". There are three read operations: current address read, random address read and sequential read. Current Address Read: The internal data word address counter maintains the last address accessed during the last read or write operation, incremented by one. This address stays valid between operations as long as the chip power is maintained. The address "roll over" during read is from the last byte of the last memory page to the first byte of the first page. The address "roll over" during write is from the last byte of the current page to the first byte of the same page. Once the device address with the read/write select bit set to "1" is clocked in and acknowledged by the EEPROM, the current address data word is serially clocked out. The microcontroller does not respond with an input "0" but does generate a following stop condition (see Figure 7). Random Read: A random read requires a “dummy” byte write sequence to load in the data word address. Once the device address word and data word address are clocked in and acknowledged by the EEPROM, the microcontroller must generate another start condition. The microcontroller now initiates a current address read by sending a device address with the read/write select bit high. The EEPROM acknowledges the device address and serially clocks out the data word. The microcontroller does not respond with a “0” but does generate a following stop condition (see Figure 8). VER 1.3 7 ACE24C32/64B Two-wire Serial EEPROM Sequential Read: Sequential reads are initiated by either a current address read or a random address read. After the microcontroller receives a data word, it responds with an acknowledge. As long as the EEPROM receives an acknowledge, it will continue to increment the data word address and serially clock out sequential data words. When the memory address limit is reached, the data word address will “roll over” and the sequential read will continue. The sequential read operation is terminated when the microcontroller does not respond with a “0” but does generate a following stop condition (see Figure 9). Figure 4: Device Address Figure 5: Byte write Figure 6: Page write VER 1.3 8 ACE24C32/64B Two-wire Serial EEPROM Figure 7: Current Address Read Figure 8: Random Read Figure 9: Sequential Read VER 1.3 9 ACE24C32/64B Two-wire Serial EEPROM Pin Capacitance Applicable over recommended operating range from: TA = 25℃, f = 1.0 MHz, VCC = +1.7V. Symbol Test Condition Max Units Conditions C I/O Input / Output Capacitance (SDA) 8 pF V I/O = 0V C IN Input Capacitance (A0, A1, A2, SCL) 6 pF V IN = 0V DC Characteristics Applicable over recommended operating range from: TA = -40℃ to +85℃, VCC = +1.7V to +5.5V, (unless otherwise noted). Symbol Parameter Test Condition VCC Supply Voltage ICC1 Supply Current Read at 400kHz ICC2 Supply Current Write at 400 kHz ISB Standby Current ILI Min Typ Max Units 5.5 V 0.4 1.0 mA 2.0 3.0 mA VIN = VCC or GND 3.0 µA Input Leakage Current VIN = VCC or GND 3.0 µA ILO Output Leakage Current VOUT = VCC or GND 3.0 µA VIL1 Input Low Level VCC=1.8V to 5.5V -0.3 VCC*0.3 V VIH1 Input High Level VCC=1.8V to 5.5V VCC*0.7 VCC+0.3 V VIL2 Input Low Level VCC=1.7V -0.3 VCC*0.3 V VIH2 Input High Level VCC=1.7V VCC*0.7 VCC+0.3 V VOL3 Output Low Level IOL = 3.0 mA 0.4 V VOL2 Output Low Level IOL = 2.1 mA 0.4 V VOL1 Output Low Level IOL = 0.15 mA 0.2 V 1.7 0.05 VER 1.3 10 ACE24C32/64B Two-wire Serial EEPROM AC Characteristics Applicable over recommended operating range from: TA = -40℃ to +85℃, VCC = +1.7V to +5.5V, C L=1 TTL Gate and 100 pF (unless otherwise noted). 1.7V≦VCC<2.5V 2.5V≦VCC≦5.5V Symbol Parameter fSCL Clock Frequency, SCL TLOW Clock Pulse Width Low 1.2 0.6 µs THIGH Clock Pulse Width High 0.6 0.4 µs TI Noise Suppression Time TAA Clock Low to Data Out Valid TBUF Min Typ Max Min Typ 400 1000 50 0.05 Time the bus must be free before a new transmission can Start 0.9 Max 0.05 Units kHz 40 ns 0.55 µs 1.2 0.5 µs THD.STA Start Hold Time 0.6 0.25 µs TSU.STA Start Setup Time 0.6 0.25 µs THD.DAT Data In Hold Time 0 0 µs TSU.DAT Data In Setup Time 100 100 ns TR Inputs Rise Time 0.3 0.3 µs TF Inputs Fall Time 300 100 ns TSU.STO Stop Setup Time 0.6 0.25 µs TDH Data Out Hold Time 50 50 ns TWR Write Cycle Time (for 04B/16B) Endurance 5.0V, 25℃, Page Mode 1.5 5 1M 1.5 5 ms Write Cycles Notes:1. This parameter is characterized and not 100% tested. 2.AC measurement conditions: RL (connects to Vcc): 1.3kΩ(2.5V,5V),10kΩ(1.7V) Input pulse voltages: 0.3 Vcc to 0.7 Vcc Input rise and fall times: ≦50 ns Input and output timing reference voltages: 0.5Vcc The value of RL should be concerned according to the actual loading on the user’s system. VER 1.3 11 ACE24C32/64B Two-wire Serial EEPROM Figure 10． SCL: Serial Clock, SDA: Serial Data I/O Figure 11． SCL: Serial Clock, SDA: Serial Data I/O Note: The write cycle time tWR is the time from a valid stop condition of a write sequence to the end of the internal clear/write cycle. VER 1.3 12 ACE24C32/64B Two-wire Serial EEPROM Packaging information DIP-8 VER 1.3 13 ACE24C32/64B Two-wire Serial EEPROM Packaging information SOP-8 VER 1.3 14 ACE24C32/64B Two-wire Serial EEPROM Packaging information TSSOP-8 VER 1.3 15 ACE24C32/64B Two-wire Serial EEPROM Packaging information MSOP-8 VER 1.3 16 ACE24C32/64B Two-wire Serial EEPROM Packaging information TDFN VER 1.3 17 ACE24C32/64B Two-wire Serial EEPROM Notes ACE does not assume any responsibility for use as critical components in life support devices or systems without the express written approval of the president and general counsel of ACE Electronics Co., LTD. As sued 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 shoes 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. 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. ACE Technology Co., LTD. http://www.ace-ele.com/ VER 1.3 18