M24164-BN1T

M24164 16 Kbit Serial I²C Bus EEPROM with 1 Inverting and 2 Non-Inverting Chip Enable Lines FEATURES SUMMARY 2 s Two Wire I C Serial Interface Supports 400 kHz Protocol s Figure 1. Packages Single Supply Voltage: – 4.5V to 5.5V for M24164 – 2.5V to 5.5V for M24164-W s s s s s s s s Write Control Input BYTE and PAGE WRITE (up to 16 Bytes) RANDOM and SEQUENTIAL READ Modes Self-Timed Programming Cycle Automatic Address Incrementing Enhanced ESD/Latch-Up Behavior More than 1 Million Erase/Write Cycles More than 40 Year Data Retention 8 1 PDIP8 (BN) 0.25 mm frame 8 1 SO8 (MN) 150 mil width October 2001 1/21 M24164 SUMMARY DESCRIPTION The M24164 is a 16 Kbit (2048 x 8) electrically erasable programmable memory (EEPROM) accessed by an I2C-compatible bus. Figure 2. Logic Diagram following the bus master’s 8-bit transmission. When data is read by the bus master, the bus master acknowledges the receipt of the data byte in the same way. Data transfers are terminated by a Stop condition after an Ack for Write, and after a NoAck for Read. Figure 3. DIP Connections VCC 3 E0-E2 SCL WC M24164 SDA E0 E1 E2 VSS M24164 1 2 3 4 8 7 6 5 AI02265B VCC WC SCL SDA VSS AI02264 Figure 4. SO Connections Table 1. Signal Names E0, E1, E2 SDA SCL WC VCC VSS Chip Enable Serial Data Serial Clock Write Control Supply Voltage Ground M24164 E0 E1 E2 VSS 1 2 3 4 8 7 6 5 AI02266B VCC WC SCL SDA These devices are compatible with a two-wire serial interface that uses a bi-directional data bus and serial clock. By setting the three chip enables (E0, E1, E2) appropriately, up to eight 16 Kbit devices can be attached to the same I2C bus, and selected individually. These devices behave as slave devices, with all memory operations synchronized by the serial clock. Read and Write operations are initiated by a Start condition, generated by the bus master. The Start condition is followed by a Device Select Code and RW bit (as described in Table 2), terminated by an acknowledge bit. When writing data to the memory, the device inserts an acknowledge bit during the 9th bit time, Power On Reset: V CC Lock-Out Write Protect In order to prevent data corruption and inadvertent Write operations during Power-up, a Power On Reset (POR) circuit is included. The internal reset is held active until VCC has reached the POR threshold value, and all operations are disabled – the device will not respond to any command. In the same way, when VCC drops from the operating voltage, below the POR threshold value, all operations are disabled and the device will not respond to any command. A stable and valid VCC must be applied before applying any logic signal. 2/21 M24164 SIGNAL DESCRIPTION Serial Clock (SCL) This input signal is used to strobe all data in and out of the device. In applications where this signal is used by slave devices to synchronize the bus to a slower clock, the bus master must have an open drain output, and a pull-up resistor must be connected from Serial Clock (SCL) to VCC. (Figure 4 indicates how the value of the pull-up resistor can be calculated). In most applications, though, this method of synchronization is not employed, and so the pull-up resistor is not necessary, provided that the bus master has a push-pull (rather than open drain) output. Serial Data (SDA) This bi-directional signal is used to transfer data in or out of the device. It is an open drain output that may be wire-OR’ed with other open drain or open collector signals on the bus. A pull up resistor must be connected from Serial Data (SDA) to V CC. (Fig- ure 4 indicates how the value of the pull-up resistor can be calculated). Chip Enable (E0, E1, E2) These input signals are used to set the value that is to be looked for on three bits (b6, b5, b4) of the 7-bit Device Select Code. These inputs must be tied to V CC or VSS, to establish the Device Select Code. Write Control (WC ) This input signal is useful for protecting the entire contents of the memory from inadvertent write operations. Write operations are disabled to the entire memory array when Write Control (WC) is driven High. When unconnected, the signal is internally read as VIL, and Write operations are allowed. When Write Control (WC) is driven High, Device Select and Address bytes are acknowledged, Data bytes are not acknowledged. Figure 5. Maximum R L Value versus Bus Capacitance (CBUS) for an I2C Bus VCC 20 Maximum RP value (kΩ) 16 RL 12 8 4 0 10 100 CBUS (pF) AI01665 RL SDA MASTER fc = 100kHz fc = 400kHz SCL CBUS CBUS 1000 3/21 M24164 DEVICE OPERATION The device supports the I2C protocol. This is summarized in Figure 2. Any device that sends data on to the bus is defined to be a transmitter, and any device that reads the data to be a receiver. The device that controls the data transfer is known as the bus master, and the other as the slave device. A data transfer can only be initiated by the bus master, which will also provide the serial clock for synchronization. The M24164 device is always a slave in all communication. Start Condition Start is identified by a falling edge of Serial Data (SDA) while Serial Clock (SCL) is stable in the High state. A Start condition must precede any data transfer command. The device continuously monitors (except during a Write cycle) Serial Data (SDA) and Serial Clock (SCL) for a Start condition, and will not respond unless one is given. Stop Condition Stop is identified by a rising edge of Serial Data (SDA) while Serial Clock (SCL) is stable and driven High. A Stop condition terminates communication between the device and the bus master. A Read command that is followed by NoAck can be followed by a Stop condition to force the device into the Stand-by mode. A Stop condition at the end of a Write command triggers the internal EEPROM Write cycle. Acknowledge Bit (ACK) The acknowledge bit is used to indicate a successful byte transfer. The bus transmitter, whether it be bus master or slave device, releases Serial Data (SDA) after sending eight bits of data. During the 9th clock pulse period, the receiver pulls Serial Data (SDA) Low to acknowledge the receipt of the eight data bits. Table 2. Device Select Code 1 Device Type Identifier b7 Device Select Code 1 Chip Enable Address b6 E2 b5 E1 b4 E0 Most Significant Address Bits b3 A10 b2 A9 b1 A8 RW b0 RW Data Input During data input, the device samples Serial Data (SDA) on the rising edge of Serial Clock (SCL). For correct device operation, Serial Data (SDA) must be stable during the rising edge of Serial Clock (SCL), and the Serial Data (SDA) signal must change only when Serial Clock (SCL) is driven Low. Memory Addressing To start communication between the bus master and the slave device, the bus master must initiate a Start condition. Following this, the bus master sends eight bits, on Serial Data (SDA), most significant bit first. These consist of the 7-bit Device Select Code, and the Read/Write bit (RW), as shown in Table 2. This last bit is set to 1 for Read, and 0 for Write operations. The Device Select Code contains the three most significant bits of the address within the memory (A10, A9, A8), and a 3-bit Chip Enable “Address” (E2, E1, E0). When the Device Select Code is received on Serial Data (SDA), the device only responds if the Chip Enable Address is the same as the value on the Chip Enable (E0, E2, and the inverse of E1) inputs. Up to eight devices can be connected on the same bus, giving a total memory capacity of 128 Kbits, 16 KBytes. If a match occurs on the Device Select code, the corresponding device gives an acknowledgment on Serial Data (SDA) during the 9th bit time. If the device does not match the Device Select code, it deselects itself from the bus, and goes into Standby mode. Note: 1. The most significant bit, b7, is sent first. 4/21 M24164 Figure 6. I2C Bus Protocol SCL SDA SDA Input SDA Change START Condition STOP Condition SCL 1 2 3 7 8 9 SDA MSB ACK START Condition SCL 1 2 3 7 8 9 SDA MSB ACK STOP Condition AI00792B Table 3. Operating Modes Mode Current Address Read Random Address Read 1 Sequential Read Byte Write Page Write Note: 1. X = VIH or VIL. RW bit 1 0 WC 1 X X Bytes 1 1 Initial Sequence START, Device Select, RW = 1 START, Device Select, RW = 0, Address reSTART, Device Select, RW = 1 X X VIL VIL ≥1 1 1 0 0 Similar to Current or Random Address Read START, Device Select, RW = 0 ≤ 16 START, Device Select, RW = 0 5/21 M24164 Figure 7. Write Mode Sequences with WC=1 (data write inhibited) WC ACK Byte Write START DEV SEL R/W ACK NO ACK DATA IN STOP ACK NO ACK DATA IN 1 BYTE ADDR WC ACK Page Write START DEV SEL R/W NO ACK DATA IN 3 BYTE ADDR DATA IN 2 WC (cont'd) NO ACK Page Write (cont'd) NO ACK DATA IN N STOP AI02803C Write Operations Following a Start condition the bus master sends a Device Select Code with the RW bit reset to 0. The device acknowledges this, as shown in Figure 8, and waits for an address byte. The device responds to the address byte with an acknowledge bit, and then waits for the data byte. Writing to the memory may be inhibited if Write Control (WC) is driven High. Any Write instruction with Write Control (WC ) driven High (during a period of time from the Start condition until the end of the address byte) will not modify the memory contents, and the accompanying data bytes are not acknowledged, as shown in Figure 7. When the bus master generates a Stop condition immediately after the Ack bit (in the “10 th bit” time slot), either at the end of a Byte Write or a Page Write, the internal memory Write cycle is triggered. A Stop condition at any other time slot does not trigger the internal Write cycle. During the internal Write cycle, Serial Data (SDA) is disabled internally, and the device does not respond to any requests. Byte Write After the Device Select code and the address byte, the bus master sends one data byte. If the addressed location is Write-protected, by Write Control (WC) being driven High, the device replies with NoAck, and the location is not modified. If, instead, the addressed location is not Write-protected, the device replies with Ack. The bus master terminates the transfer by generating a Stop condition, as shown in Figure 8. Page Write The Page Write mode allows up to 16 bytes to be written in a single Write cycle, provided that they are all located in the same ’row’ in the memory: 6/21 M24164 that is, the most significant memory address bits are the same. If more bytes are sent than will fit up to the end of the row, a condition known as ‘rollover’ occurs. This should be avoided, as data starts to become overwritten in an implementation dependent way. The bus master sends from 1 to 16 bytes of data, each of which is acknowledged by the device if Write Control (WC) is Low. If Write Control (WC) is High, the contents of the addressed memory location are not modified, and each data byte is followed by a NoAck. After each byte is transferred, the internal byte address counter (the 4 least significant address bits only) is incremented. The transfer is terminated by the bus master generating a Stop condition. Figure 8. Write Mode Sequences with WC=0 (data write enabled) WC ACK BYTE WRITE START DEV SEL R/W ACK DATA IN STOP ACK DATA IN 1 ACK DATA IN 2 ACK BYTE ADDR WC ACK PAGE WRITE START DEV SEL R/W ACK DATA IN 3 BYTE ADDR WC (cont'd) ACK PAGE WRITE (cont'd) DATA IN N ACK STOP AI02804 7/21 M24164 Figure 9. Write Cycle Polling Flowchart using ACK WRITE Cycle in Progress START Condition DEVICE SELECT with RW = 0 NO First byte of instruction with RW = 0 already decoded by the device ACK Returned YES NO Next Operation is Addressing the Memory YES ReSTART Send Address and Receive ACK STOP NO START Condition YES DATA for the WRITE Operation DEVICE SELECT with RW = 1 Continue the WRITE Operation Continue the Random READ Operation AI01847C Minimizing System Delays by Polling On ACK During the internal Write cycle, the device disconnects itself from the bus, and writes a copy of the data from its internal latches to the memory cells. The maximum Write time (tw) is shown in Tables 11 and 12, but the typical time is shorter. To make use of this, a polling sequence can be used by the bus master. The sequence, as shown in Figure 9, is: – Initial condition: a Write cycle is in progress. – Step 1: the bus master issues a Start condition followed by a Device Select Code (the first byte of the new instruction). – Step 2: if the device is busy with the internal Write cycle, no Ack will be returned and the bus master goes back to Step 1. If the device has terminated the internal Write cycle, it responds with an Ack, indicating that the device is ready to receive the second part of the instruction (the first byte of this instruction having been sent during Step 1). 8/21 M24164 Figure 10. Read Mode Sequences ACK CURRENT ADDRESS READ START DEV SEL R/W NO ACK DATA OUT STOP ACK DEV SEL * START R/W ACK RANDOM ADDRESS READ START DEV SEL * R/W ACK NO ACK DATA OUT STOP NO ACK ACK AI01942 BYTE ADDR ACK SEQUENTIAL CURRENT READ START DEV SEL R/W ACK ACK DATA OUT 1 DATA OUT N STOP ACK SEQUENTIAL RANDOM READ START DEV SEL * R/W ACK DEV SEL * START ACK BYTE ADDR DATA OUT 1 R/W ACK NO ACK DATA OUT N STOP Note: 1. The seven most significant bits of the Device Select Code of a Random Read (in the 1 st and 3rd bytes) must be identical. Read Operations Read operations are performed independently of the state of the Write Control (WC) signal. Random Address Read A dummy Write is performed to load the address into the address counter (as shown in Figure 10) but without sending a Stop condition. Then, the bus master sends another Start condition, and repeats the Device Select Code, with the RW bit set to 1. The device acknowledges this, and outputs the contents of the addressed byte. The bus mas- ter must not acknowledge the byte, and terminates the transfer with a Stop condition. Current Address Read The device has an internal address counter which is incremented each time a byte is read. For the Current Address Read operation, following a Start condition, the bus master only sends a Device Select Code with the RW bit set to 1. The device acknowledges this, and outputs the byte addressed by the internal address counter. The counter is then incremented. The bus master terminates the 9/21 M24164 transfer with a Stop condition, as shown in Figure 10, without acknowledging the byte. Sequential Read This operation can be used after a Current Address Read or a Random Address Read. The bus master does acknowledge the data byte output, and sends additional clock pulses so that the device continues to output the next byte in sequence. To terminate the stream of bytes, the bus master must not acknowledge the last byte, and must generate a Stop condition, as shown in Figure 10. The output data comes from consecutive addresses, with the internal address counter automatically incremented after each byte output. After the last memory address, the address counter ‘rolls-over’, and the device continues to output data from memory address 00h. Acknowledge in Read Mode For all Read commands, the device waits, after each byte read, for an acknowledgment during the 9th bit time. If the bus master does not drive Serial Data (SDA) Low during this time, the device terminates the data transfer and switches to its Standby mode. 10/21 M24164 MAXIMUM RATING Stressing the device above the rating listed in the Absolute Maximum Ratings" table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other conditions above those indicated in the Operating sections of this specification is not imTable 4. Absolute Maximum Ratings Symbol TSTG TLEAD VIO VCC VESD Storage Temperature Lead Temperature during Soldering Input or Output range Supply Voltage Electrostatic Discharge Voltage (Human Body model) 2 PDIP: 10 seconds SO: 20 seconds (max) 1 –0.6 –0.3 –4000 Parameter Min. –65 Max. 150 260 235 6.5 6.5 4000 Unit °C °C V V V plied. Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability. Refer also to the STMicroelectronics SURE Program and other relevant quality documents. Note: 1. IPC/JEDEC J-STD-020A 2. JEDEC Std JESD22-A114A (C1=100 pF, R1=1500 Ω, R2=500 Ω) 11/21 M24164 DC AND AC PARAMETERS This section summarizes the operating and measurement conditions, and the DC and AC characteristics of the device. The parameters in the DC and AC Characteristic tables that follow are derived from tests performed under the MeasureTable 5. Operating Conditions (M24164) Symbol VCC TA Supply Voltage Ambient Operating Temperature Parameter Min. 4.5 0 Max. 5.5 70 Unit V °C ment Conditions summarized in the relevant tables. Designers should check that the operating conditions in their circuit match the measurement conditions when relying on the quoted parameters. Table 6. Operating Conditions (M24164-W) Symbol VCC TA Supply Voltage Ambient Operating Temperature Parameter Min. 2.5 0 Max. 5.5 70 Unit V °C Table 7. AC Measurement Conditions Symbol CL Load Capacitance Input Rise and Fall Times Input Pulse Voltages Input and Output Timing Reference Voltages Note: 1. Output Hi-Z is defined as the point where data out is no longer driven. Parameter Min. 30 Max. Unit pF 50 0.2VCC to 0.8VCC 0.3VCC to 0.7VCC ns V V Figure 11. AC Measurement I/O Waveform 0.8VCC 0.7VCC 0.3VCC AI00825 0.2VCC 12/21 M24164 Table 8. Capacitance Symbol CIN CIN tNS Parameter1,2 Input Capacitance (SDA) Input Capacitance (other pins) Pulse width ignored (Input Filter on SCL and SDA) Single glitch Test Condition Min. Max. 8 6 100 Unit pF pF ns Note: 1. TA = 25 °C, f = 400 kHz 2. Sampled only, not 100% tested. Table 9. DC Characteristics (M24164) Symbol ILI ILO ICC ICC1 VIL VIH VIL VIH VOL Parameter Input Leakage Current (SCL, SDA) Output Leakage Current Supply Current Stand-by Supply Current Input Low Voltage (E0, E1, E2, SCL, SDA) Input High Voltage (E0, E1, E2, SCL, SDA) Input Low Voltage (WC) Input High Voltage (WC) Output Low Voltage IOL = 3 mA, 4.5 V ≤ VCC ≤ 5.5 V Test Condition (in addition to those in Table 5) VIN = VSS or VCC 0 V ≤ VOUT ≤ VCC, SDA in Hi-Z VCC =5V, fc=400kHz (rise/fall time < 30ns) VIN = VSS or VCC , VCC = 5 V – 0.3 0.7VCC – 0.3 0.7VCC Min. Max. ±2 ±2 2 20 0.3VCC VCC+1 0.5 VCC+1 0.4 Unit µA µA mA µA V V V V V Table 10. DC Characteristics (M24164-W) Symbol ILI ILO ICC ICC1 VIL VIH VIL VIH VOL Parameter Input Leakage Current (SCL, SDA) Output Leakage Current Supply Current Stand-by Supply Current Input Low Voltage (E0, E1, E2, SCL, SDA) Input High Voltage (E0, E1, E2, SCL, SDA) Input Low Voltage (WC) Input High Voltage (WC) Output Low Voltage IOL = 2.1 mA, 2.5 V ≤ VCC ≤ 5.5 V Test Condition (in addition to those in Table 6) VIN = VSS or VCC 0 V ≤ VOUT ≤ VCC, SDA in Hi-Z VCC =2.5V, fc=400kHz (rise/fall time < 30ns) VIN = VSS or VCC , VCC = 5 V – 0.3 0.7VCC – 0.3 0.7VCC Min. Max. ±2 ±2 1 1 0.3VCC VCC+1 0.5 VCC+1 0.4 Unit µA µA mA µA V V V V V 13/21 M24164 Table 11. AC Characteristics (M24164) Test conditions specified in Table 7 and Table 5 Symbol fC tCH1CH2 tCL1CL2 tCHCL tCLCH tDH1DH2 2 tDL1DL2 2 tDXCX tCLDX tCLQX tCLQV 3 tCHDX 1 tDLCL tCHDH tDHDL tW Alt. fSCL tR tF tHIGH tLOW tR tF tSU:DAT tHD:DAT tDH tAA tSU:STA tHD:STA tSU:STO tBUF tWR Clock Frequency Clock Rise Time Clock Fall Time Clock Pulse Width High Clock Pulse Width Low SDA Rise Time SDA Fall Time Data In Set Up Time Data In Hold Time Data Out Hold Time Clock Low to Next Data Valid (Access Time) Start Condition Set Up Time Start Condition Hold Time Stop Condition Set Up Time Time between Stop Condition and Next Start Condition Write Time 20 20 600 1300 20 20 100 0 200 200 600 600 600 1300 5 900 300 300 Parameter Min. Max. 400 300 300 Unit kHz ns ns ns ns ns ns ns ns ns ns ns ns ns ns ms Note: 1. For a reSTART condition, or following a Write cycle. 2. Sampled only, not 100% tested. 3. To avoid spurious START and STOP conditions, a minimum delay is placed between SCL=1 and the falling or rising edge of SDA. 14/21 M24164 Table 12. AC Characteristics (M24164-W) Test conditions specified in Table 7 and Table 6 Symbol fC tCH1CH2 tCL1CL2 tCHCL tCLCH tDH1DH2 2 tDL1DL2 2 tDXCX tCLDX tCLQX tCLQV 3 tCHDX 1 tDLCL tCHDH tDHDL tW Alt. fSCL tR tF tHIGH tLOW tR tF tSU:DAT tHD:DAT tDH tAA tSU:STA tHD:STA tSU:STO tBUF tWR Clock Frequency Clock Rise Time Clock Fall Time Clock Pulse Width High Clock Pulse Width Low SDA Rise Time SDA Fall Time Data In Set Up Time Data In Hold Time Data Out Hold Time Clock Low to Next Data Valid (Access Time) Start Condition Set Up Time Start Condition Hold Time Stop Condition Set Up Time Time between Stop Condition and Next Start Condition Write Time 20 20 600 1300 20 20 100 0 200 200 600 600 600 1300 10 900 300 300 Parameter Min. Max. 400 300 300 Unit kHz ns ns ns ns ns ns ns ns ns ns ns ns ns ns ms Note: 1. For a reSTART condition, or following a Write cycle. 2. Sampled only, not 100% tested. 3. To avoid spurious START and STOP conditions, a minimum delay is placed between SCL=1 and the falling or rising edge of SDA. 15/21 M24164 Figure 12. AC Waveforms tCHCL tCLCH SCL tDLCL SDA In tCHDX START Condition SDA Input tCLDX SDA tDXCX Change tCHDH tDHDL START STOP Condition Condition SCL SDA In tCHDH STOP Condition tW Write Cycle tCHDX START Condition SCL tCLQV SDA Out Data Valid tCLQX AI00795C 16/21 M24164 PACKAGE MECHANICAL PDIP8 – 8 pin Plastic DIP, 0.25mm lead frame b2 A2 A1 b e A L E c eA eB D 8 E1 1 PDIP-B Notes: 1. Drawing is not to scale. PDIP8 – 8 pin Plastic DIP, 0.25mm lead frame mm Symb. Typ. A A1 A2 b b2 c D E E1 e eA eB L 3.30 2.92 3.30 0.46 1.52 0.25 9.27 7.87 6.35 2.54 7.62 0.38 2.92 0.36 1.14 0.20 9.02 7.62 6.10 – – 4.95 0.56 1.78 0.36 10.16 8.26 7.11 – – 10.92 3.81 0.130 0.115 0.130 0.018 0.060 0.010 0.365 0.310 0.250 0.100 0.300 Min. Max. 5.33 0.015 0.115 0.014 0.045 0.008 0.355 0.300 0.240 – – 0.195 0.022 0.070 0.014 0.400 0.325 0.280 – – 0.430 0.150 Typ. Min. Max. 0.210 inches 17/21 M24164 SO8 narrow – 8 lead Plastic Small Outline, 150 mils body width h x 45˚ A C B e D CP N E 1 H A1 α L SO-a Note: Drawing is not to scale. SO8 narrow – 8 lead Plastic Small Outline, 150 mils body width mm Symb. Typ. A A1 B C D E e H h L α N CP 1.27 Min. 1.35 0.10 0.33 0.19 4.80 3.80 – 5.80 0.25 0.40 0° 8 0.10 Max. 1.75 0.25 0.51 0.25 5.00 4.00 – 6.20 0.50 0.90 8° 0.050 Typ. Min. 0.053 0.004 0.013 0.007 0.189 0.150 – 0.228 0.010 0.016 0° 8 0.004 Max. 0.069 0.010 0.020 0.010 0.197 0.157 – 0.244 0.020 0.035 8° inches 18/21 M24164 PART NUMBERING Table 13. Ordering Information Scheme Example: Device Type M24 = I2C serial access EEPROM Device Function 164 = 16 Kbit (2048 x 8) Operating Voltage blank = VCC = 4.5 to 5.5V W = VCC = 2.5 to 5.5V Package BN = PDIP8 (0.25 mm frame) MN = SO8 (150 mil width) Temperature Range 1 = 0 to 70 °C Option T = Tape & Reel Packing M24164 – W MN 1 T For a list of available options (speed, package, etc.) or for further information on any aspect of this device, please contact your nearest ST Sales Office. 19/21 M24164 REVISION HISTORY Table 14. Document Revision History Date Jan-1999 23-Oct-2001 Rev. 1.0 2.0 Document written Document reformatted. -R voltage range taken out Description of Revision 20/21 M24164 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is registered trademark of STMicroelectronics All other names are the property of their respective owners © 2001 STMicroelectronics - All Rights Reserved STMicroelectronics group of companies Austalia - Brazil - Canada - China - Finland - France - Germany - Hong Kong India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States. www.st.com 21/21