Double-cell Memory for Plug & Play DDR1/DDR2 (For memory module) SPD Memory BR34L02FV-W No.09002EAT04 ●Description BR34L02FV-W is 256×8 bit Electrically Erasable PROM (Based on Serial Presence Detect) ●Features 1) 256×8 bit architecture serial EEPROM 2) Wide operating voltage range: 1.7V-5.5V 3) Two-wire serial interface 4) High reliability connection using Au pads and Au wires 5) Self-Timed Erase and Write Cycle 6) Page Write Function (16byte) 7) Write Protect Mode Write Protect 1 (Onetime Rom) : 00h-7Fh Write Protect 2 (Hardwire WP PIN) : 00h-FFh 8) Low Power consumption Write ( at 5V ) :1.2mA (typ.) Read ( at 5V ) :0.2mA(typ.) Standby ( at 5V ) :0.1µA(typ.) 9) DATA security Write protect feature (WP pin) Inhibit to WRITE at low VCC 10) Compact package: SSOP-B8 11) High reliability fine pattern CMOS technology 12) Rewriting possible up to 1,000,000 times 13) Data retention: 40 years 14) Noise reduction Filtered inputs in SCL / SDA 15) Initial data FFh at all addresses ●Absolute Maximum Ratings (Ta=25℃) Parameter Symbol Supply Voltage VCC Power Dissipation Pd Storage Temperature Tstg Operating Temperature Topr Terminal Voltage - Rating -0.3～+6.5 300* -65～+125 -40～+85 -0.3～VCC+0.3 Unit V mW ℃ ℃ V Rating 1.7～5.5 0～VCC Unit V V * Reduce by 3.0 mW/C over 25C ●Recommended operating conditions Parameter Symbol Supply Voltage VCC Input Voltage ＶIN ●Memory cell characteristics(Ta=25℃, VCC=1.7V～5.5V) Specification Parameter Min. Typ. Max. Unit Write / Erase Cycle *1 1,000,000 - - Cycles Data Retention *1 40 - - Years *1:Not 100% TESTED www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 1/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Electrical characteristics - DC(Unless otherwise specified Ta=-40℃～+85℃, VCC=1.7V～5.5V) Specification Parameter Symbol Unit Min. Typ. Max. Test Condition "H" Input Voltage 1 VIH1 0.7 VCC - - V 2.5V≦VCC≦5.5V "L" Input Voltage 1 VIL1 - - 0.3 VCC V 2.5V≦VCC≦5.5V "H" Input Voltage 2 VIH2 0.8 VCC - - V 1.7V≦VCC＜2.5V "L" Input Voltage 2 VIL2 - - 0.2 VCC V 1.7V≦VCC＜2.5V "L" Output Voltage 1 VOL1 - - 0.4 V IOL=3.0mA，2.5V≦VCC≦5.5V(SDA) "L" Output Voltage 2 VOL2 - - 0.2 V IOL=0.7mA，1.7V≦VCC＜2.5V(SDA) Input Leakage Current 1 ILI1 -1 - 1 µA VIN=0V～VCC(A0,A1,A2,SCL) Input Leakage Current 2 ILI2 -1 - 15 µA VIN=0V～VCC(WP) Output Leakage Current ILO -1 - 1 µA VOUT=0V～VCC (SDA) ICC1 - - 2.0 mA ICC2 - - 0.5 mA ISB - - 2.0 µA Operating Current Standby Current VCC=5.5V,fSCL=400kHz，tWR=5ms Byte Write Page Write Write Protect VCC =5.5V,fSCL=400kHz Random Read Current Read Sequential Read VCC =5.5V,SDA,SCL= VCC A0,A1,A2=GND,WP=GND ○Note: This IC is not designed to be radiation-resistant. ●Electrical characteristics - AC(Unless otherwise specified Ta=-40℃～+85℃, VCC =1.7V～5.5V) FAST-MODE STANDARD-MODE 2.5V≦VCC≦5.5V 1.7V≦VCC≦5.5V Parameter Symbol Min. Typ. Max. Min. Typ. Max. Clock Frequency fSCL 400 100 Data Clock High Period tHIGH 0.6 4.0 Data Clock Low Period tLOW 1.2 4.7 SDA and SCL Rise Time *1 tR 0.3 1.0 SDA and SCL Fall Time *1 tF 0.3 0.3 Start Condition Hold Time tHD:STA 0.6 4.0 Start Condition Setup Time tSU:STA 0.6 4.7 Input Data Hold Time tHD:DAT 0 0 Input Data Setup Time tSU:DAT 50 50 Output Data Delay Time tPD 0.1 0.9 0.2 3.5 Output Data Hold Time tDH 0.1 0.2 Stop Condition Setup Time tSU:STO 0.6 4.7 Bus Free Time tBUF 1.2 4.7 Write Cycle Time tWR 5 5 Noise Spike Width (SDA and SCL) tI 0.1 0.1 WP Hold Time tHD：WP 0 0 WP Setup Time tSU：WP 0.1 0.1 WP High Period tHIGH：WP 1.0 1.0 - Unit kHz µs µs µs µs µs µs ns ns µs µs µs µs ms µs ns µs µs *1：Not 100％ TESTED ■Fast / Standard Modes Fast mode and Standard mode differ only in operation frequency. Operations performed at 100kHz are considered in "Standard-mode", while those conducted at 400kHz are in "Fast-mode". Please note that these clock frequencies are maximum values. At lower power supply voltage it is difficult to operate at high speeds. The EEPROM can operate at 400kHz, between 2.5V and 5.5V, and at 100kHz from 1.7V-5.5V. www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 2/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Synchronous Data Timing tR tF tHIGH SCL SCL tSU:DAT tLOW tHD:STA tHD:DAT tSU:STA SDA (IN) tBUF tPD tHD:STA tSU:STO SDA tDH SDA (OUT) START BIT STOP BIT Fig.1-(b) Start/Stop Bit Timing Fig.1-(a) Synchronous Data Timing ○SDA data is latched into the chip at the rising edge ○ of SCL clock. ○Output data toggles at the falling edge of SCL clock. SCL SCL DATA(1) SDA SDA D0 D1 D0 DATA(n) ACK ACK ｔWR ACK tWR WRITE DATA(n) STOP CONDITION Stop Condition WP START CONDITION tSU：WP ｔHD：WP Fig.1-(d) WP Timing Of The Write Operation Fig.1-(c) Write Cycle Timing SCL DATA(n) DATA(1) SDA D1 D0 ACK ACK tHIGH:WP tWR WP Fig.1-(e) WP Timing Of The Write Cancel Operation ○For WRITE operation, WP must be "Low" from the rising edge of the clock (which takes in D0 of first byte) until the end of tWR. (See Fig.1-(d) ) During this period, WRITE operation can be canceled by setting WP "High".（See Fig.1-(e)） ○When WP is set to "High" during tWR, WRITE operation is immediately ceased, making the data unreliable. It must then be re-written. www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 3/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Block diagram A0 1 2 Kbit EEPROM ARRAY ADDRESS 2 DECODER 8bit SLAVE , WORD DATA ADDRESS REGISTER REGISTER START A2 3 VCC 7 WP 6 SCL 5 SDA 8bit 8bit A1 8 STOP CONTOROL LOGIC ACK GND 4 HIGH VOLTAGE GEN. VCC LEVEL DETECT Fig.2 Block Diagram ●Pinout diagram and description Pin Name Input/Output 7 WP VCC GND A0,A1,A2 SCL IN IN A2 3 6 SCL SDA IN / OUT GND 4 5 SDA WP IN A0 1 8 VCC A1 2 Functions Power Supply Ground 0V Slave Address Set. Serial Clock Input BR34L02FV-W Slave and Word Address, Serial Data Input, Serial Data Output *1 Write Protect Input *2 *1 Open drain output requires a pull-up resistor. *2 WP Pin has a Pull-Down resistor. Please leave unconnected or connect to GND when not in use. Fig.3 Pin Configuration 6 5 5 4 4 SPEC 3 0.8 Ta=85℃ Ta=-40℃ Ta=25℃ 3 2 Ta=85℃ Ta=-40℃ Ta=25℃ 2 1 VOL1[V] 6 VIL1,2[V] VIH1,2[V] ●Electrical characteristics curves The following characteristic data are typ. value. SPEC Ta=85℃ 0.4 Ta=25℃ 0.2 1 1 0.6 SPEC Ta=-40℃ 0 0 0 1 2 3 4 5 0 0 6 1 2 3 4 5 6 0 1 2 V CC [V] VCC[V] Fig.4 "H" Input Voltage VIH1,2 (A0,A1,A2,SCL,SDA,WP) 5 6 16 1.2 SPEC SPEC 1 0.8 4 Fig.6 "L" Output Voltage VOL1-IOL1 (VCC=2.5V) Fig.5 "L" Input Voltage VIL1,2 (A0,A1,A2,SCL,SDA,WP) 1 3 IOL1[mA] 12 Ta=85℃ Ta=25℃ 0.4 ILI2[μA] ILI1[μA] VOL2[V] 0.8 0.6 0.6 8 Ta=85℃ Ta=25℃ Ta=-40℃ 0.4 SPEC 0.2 0.2 Ta=-40℃ 4 Ta=85℃ Ta=25℃ Ta=-40℃ 0 0 0 0 1 2 3 4 5 6 IOL2[mA] Fig.7 "L" Output Voltage VOL2-IOL2 (VCC=1.7V) www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 0 1 2 3 4 5 6 V CC [V] Fig.8 Input Leakage Current ILI1 (A0,A1,A2,SCL,SDA) 4/17 0 1 2 3 4 5 6 V CC [V] Fig.9 Input Leakage Current ILI2 (WP) 2009.04 - Rev.A Technical Note BR34L02FV-W 2.5 0.6 SPEC SPEC Ta=25℃ Ta=85℃ Ta=-40℃ 0.5 0.5 0.5 fSCL=400kHz 0.4 DATA=AAh 0.4 ICC2[mA] 1 ICC2[mA] ICC1[mA] fSCL=400kHz(VCC≧2.5V) fSCL=100kHz(1.7V≦Vcc＜2.5V) DATA=AA 1.5 0.6 SPEC 2 0.3 Ta=25℃ Ta=85℃ fSCL=100kHz DATA=AAh 0.3 Ta=85℃ 0.2 Ta=25℃ 0.2 Ta=-40℃ 0.1 0.1 Ta=-40℃ 0 0 0 1 2 3 4 5 0 0 6 1 2 VCC[V] 3 4 Fig.10 Write Operating Current ICC1 (fSCL=100kHz,400kHz) 0 10000 2 1 SPEC1 1 2 SPEC2 4 5 1 2 3 4 5 6 0 3 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 2 SPEC1 Ta=85℃ Ta=25℃ Ta=-40℃ 1 Ta=-40℃ Ta=25℃ Ta=85℃ SPEC1 1 3 4 5 1 2 Fig.16 Data Clock Low Period tLow 3 4 5 6 Ta=-40℃ Ta=25℃ Ta=85℃ SPEC1 0 1 2 3 4 5 6 VCC[V] Fig.17 Start Condition Hold Time tHD:STA 50 Fig.18 Start Condition Setup Time tSU:STA 50 200 SPEC1,2 SPEC1,2 Ta=85℃ Ta=25℃ Ta=-40℃ -50 -100 0 SPEC1:FAST-MODE SPEC2:STANDARD-MODE -50 Ta=85℃ -100 -150 SPEC1:FAST-MODE SPEC2:STANDARD-MODE tSU:DAT(HIGH)[ns] tHD:DAT(LOW)[μs] 0 Ta=-40℃ Ta=25℃ -200 -200 3 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 2 VCC[V] VCC[V] 2 6 0 0 6 3 1 0 0 1 5 SPEC2 4 tSU:STA[μs] tHD:STA[μs] 2 0 4 5 4 SPEC1:FAST-MODE SPEC2:STANDARD-MODE -150 3 SPEC2 4 2 2 Fig.15 Data Clock High Period tHigh 5 1 Ta=-40℃ Ta=85℃ V CC [V] Fig.14 Clock Frequency fSCL SPEC2 0 1 V CC [V] 5 3 Ta=25℃ SPEC1 1 0 0 6 Fig.13 Standby Current ISB tHD:DAT(HIGH)[μs] 2 SPEC1:FAST-MODE SPEC2:STANDARD-MOD Ta=25℃ 3 Vcc[V] VCC[V] 6 SPEC1:FASTE SPEC1:FAST-MODE SPEC2:STANDD-MODE SPEC2:STANDARD-MO 3 1 0 5 SPEC2 100 0 4 4 10 Ta=-40℃ 3 5 Ta=85℃ Ta=25℃ Ta=-40℃ tHIGH[μs] fSCL[kHz] 1.5 Ta=85℃ 2 Fig.12 Read Operating Current ICC2 (fSCL=100kHz) 1000 0.5 1 V CC [V] SPEC ISB[μA] 6 Fig.11 Read Operating Current ICC2 (fSCL=400kHz) 2.5 tLOW[μs] 5 V CC [V] 4 5 6 0 1 2 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 4 5 6 VCC[V] VCC[V] Fig.19 Input Data Hold Time tHD:DAT(High) 3 Fig.20 Input Data Hold Time tHD:DAT(LOW) 5/17 100 SPEC1,2 Ta=85℃ Ta=25℃ Ta=-40℃ 0 -100 SPEC1:FAST-MODE SPEC2:STANDARD-MODE -200 0 1 2 3 4 5 6 Vcc[V] VCC[V] Fig.21 Input Data Setup Time tSU:DAT(High) 2009.04 - Rev.A Technical Note BR34L02FV-W 4 4 Ta=85℃ 0 SPEC2 3 SPEC1,2 3 SPEC1:FAST-MODE SPEC1:FAST-MODE SPEC2:STANDARD-MODE SPEC2:STANDARD-MODE 2 SPEC1 -100 SPEC1 -200 0 1 Ta=85℃ Ta=25℃ Ta=-40℃ SPEC2 1 Ta=-40℃ Ta=25℃ 2 3 4 5 tDH[μs] 100 tPD[μs] tSU:DAT(Low)[ns] SPEC1:FAST-MODE SPEC2:STANDARD-MODE tDH[μs] 200 1 2 3 4 5 SPEC1 6 0 V CC [V] VCC[V] Fig.22 Input Data Setup Time tSU:DAT(Low) Fig.23 Output Data Delay Time tPD 3 SPEC1 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 2 1 2 3 4 5 1 2 3 4 5 6 0 0.6 Ta=85℃ 0.2 0.3 Ta=-40℃ 0.2 Ta=25℃ 1 2 3 4 5 0 6 1 2 VCC[V] 3 4 5 SPEC1,2 0 6 0 1 2 3 Fig.30 Noise Spike Width tI(SDA H) Ta=85℃ 1 SPEC1,2 SPEC1:FAST-MODE SPEC2:STANDARD-MODE -0.2 Ta=25℃ Ta=85℃ tHIGH:WP[μs] tSU:WP[μs] 0.3 0.8 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 0.6 0.4 -0.4 -0.6 0 2 3 4 5 6 0 0 1 2 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 3 4 5 6 0 1 2 3 4 5 6 VCC[V] VCC[V] Fig.32 WP Setup Time tSU:WP Fig.33 WP High Period tHigh:WP VCC[V] Fig.31 Noise Spike Width tI(SDA L) Ta=-40℃ Ta=25℃ Ta=85℃ 0.2 Ta=-40℃ SPEC1,2 1 6 SPEC1,2 Ta=-40℃ 0 5 1.2 0 0.4 0.1 4 VCC[V] 0.2 SPEC1:FAST-MODE SPEC2:STANDARD-MODE Ta=25℃ Ta=85℃ 0.2 Fig.29 Noise Spike Width tI(SCL L) 0.6 0.2 Ta=-40℃ Ta=25℃ 0.3 V CC [V] Fig.28 Noise Spike Width tI(SCL H) 0.5 0.4 0.1 SPEC1,2 0 0 6 Ta=85℃ 0.1 0 5 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 0.5 0.4 SPEC1,2 0.1 4 0.6 tI(SDA H)[μs] tI(SCL L)[μs] Ta=25℃ 3 Fig.27 Write Cycle Time tWR SPEC1:FAST-MODE SPEC2:STANDARD-MODE 0.5 Ta=-40℃ 0.4 0.3 2 VCC[V] 0.6 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 0.5 1 Fig.26 Bus Free Time tBUF Fig.25 Stop Condition Setup Time tSU:STO tI(SCL H)[μs] Ta=85℃ SPEC1:FAST-MODE SPEC2:STANDARD-MODE VCC[V] VCC[V] tI(SDA L)[μs] 3 0 0 6 Ta=25℃ 1 0 0 0 Ta=85℃ Ta=25℃ Ta=-40℃ SPEC1 1 Ta=85℃ Ta=25℃ Ta=-40℃ 6 Ta=-40℃ 2 1 5 5 tWR[ms] tBUF[μs] tSU:STO[μs] 2 4 SPEC1,2 SPEC2 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 3 6 4 3 2 Fig.24 Output Data Hold Time tDH 4 4 1 VCC[V] 5 SPEC2 Ta=85℃ Ta=25℃ Ta=-40℃ SPEC2 0 0 5 2 1 0 6 SPEC1:FAST-MODE SPEC2:STANDARD-MODE 6/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Data transfer on the I2C BUS ○Data transfer on the I2C BUS The BUS is considered to be busy after the START condition and free a certain time after the STOP condition. Every SDA byte must be 8-bits long and requires an ACKNOWLEDGE signal after each byte. The devices have Master and Slave configurations. The Master device initiates and ends data transfer on the BUS and generates the clock signals in order to permit transfer. The EEPROM in a slave configuration is controlled by a unique address. Devices transmitting data are referred to as the Transmitter. The devices receiving the data are called Receiver. ○START Condition (Recognition of the START bit) ・All commands are proceeded by the start condition, which is a High to Low transition of SDA when SCL is High. ・The device continuously monitors the SDA and SCL lines for the start condition and will not respond to any command until this condition has been met. (See Fig.1-(b) START/STOP Bit Timing) ○STOP Condition (Recognition of STOP bit) ・All communications must be terminated by a stop condition, which is a Low to High transition of SDA when SCL is High. (See Fig.1-(b) START/STOP Bit Timing) ○Acknowledge ・ Acknowledge is a software used to indicate successful data transfers. The Transmitter device will release the BUS after transmitting eight bits. When inputting the slave address during write or read operation, the Transmitter is the µ-COM. When outputting the data during read operation, the Transmitter is the EEPROM. ・During the ninth clock cycle the Receiver will pull the SDA line Low to verify that the eight bits of data have been received. (When inputting the slave address during write or read operation, EEPROM is the receiver. When outputting the data during read operation the receiver is the µ-COM.) ・The device will respond with an Acknowledge after recognition of a START condition and its slave address (8bit). ・In WRITE mode, the device will respond with an Acknowledge after the receipt of each subsequent 8-bit word (word address and write data). ・In READ mode, the device will transmit eight bits of data, release the SDA line, and monitor the line for an Acknowledge. ・If an Acknowledge is detected and no STOP condition is generated by the Master, the device will continue to transmit the data. If an Acknowledge is not detected, the device will terminate further data transmissions and await a STOP condition before returning to standby mode. ○Device Addressing ・Following a START condition, the Master outputs the Slave address to be accessed. The most significant four bits of the slave address are the “device type indentifier.” For this EEPROM it is “1010.” (For WP register access this code is "0110".) ・The next three bits identify the specified device on the BUS (device address). The device address is defined by the state of the A0,A1 and A2 input pins. This IC works only when the device address input from the SDA pin corresponds to the status of the A0,A1 and A2 input pins. Using this address scheme allows up to eight devices to be connected to the BUS. The last bit of the stream (R/W…READ/WRITE) determines the operation to be performed. R/W=0 R/W=1 Device Type WRITE (including word address input of Random Read) READ Device Address Read Write Mode R/W R/W Access Area 1010 A2 A1 A0 Access to Memory 0110 A2 A1 A0 Access to Write Protect Register ○Write Protect command The Write Protect command cancels any write commands that access addresses 00～7Fh. The Write Protect Register can be written to once (One time Rom). Once this command is excuted, the data is protected forever. ○Write Protect Pin (WP) When the WP pin set to Vcc (H level), write protect is set for 256 words (all addresses). WP pin set to GND (L level) enables writing of 256 words (all addresses). If permanent protection is implemented by the Write Protect command, writing is prohibited in the the lower half area (addresses 00～7Fh) regardless of the WP pin status. The WP pin has a pulldown resistor. Please leave unconnected or connect to GND when not in use. www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 7/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Command ○Write Cycle During WRITE CYCLE operation data is written in the EEPROM. The Byte Write Cycle is used to write only one byte. In the case of writing continuous data consisting of more than one byte, Page Write is used. The maximum bytes that can be written at one time is 16 bytes. S T A R T SDA LINE W R I T E SLAVE ADDRESS WORD ADDRESS WA 7 1 0 1 0 A2 A1 A0 S T O P DATA WA 0 D7 D0 A C K R A / C W K A C K Fig.34 Byte Write Cycle Timing S T A R T SDA L IN E S LA V E ADDRESS W R I T E W ORD A D D R E S S (n ) WA 7 1 0 1 0 A 2A 1A 0 R A / C W K D A TA (n) WA 0 D7 A C K S T O P D A TA (n + 1 5) D0 D0 A C K A C K Fig.35 Page Write Cycle Timing ・With this command the data is programmed into the indicated word address. ・When the Master generates a STOP condition, the device begins the internal write cycle to the nonvolatile memory array. This device is capable of sixteen-byte Page Write operations. Once programming is started no commands are accepted for tWR (5ms max.). If the Master transmits more than sixteen words prior to generating the STOP condition, the address counter will “roll over” and the previously transmitted data will be overwritten. When two or more byte of data are input, the four low order address bits are internally incremented by one after the receipt of each word, while the four higher order bits of the address (WA7～WA4) remain constant. www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 8/17 2009.04 - Rev.A Technical Note BR34L02FV-W ○Read Cycle During Read Cycle operation data is read from the EEPROM. The Read Cycle is composed of Random Read Cycle and Current Read Cycle. The Random Read Cycle reads the data in the indicated address. The Current Read Cycle reads the data in the internally indicated address and verifies the data immediately after the Write Operation. The Sequential Read operation can be performed with both Current Read and Random Read. With the Sequential Read Cycle it is possible to continuously read the next data. It is necessary to input “High” at last ACK timing. S T A R T SDA L IN E W R I T E SLAVE ADDRESS W ORD A D D R E S S (n ) WA 7 1 0 1 0 A 2 A 1A 0 S T A R T WA 0 R A / C W K SLAVE ADDRESS R E A D S T O P D A TA (n) 1 0 1 0 A 2 A 1A 0 D7 D0 A C K R A / C W K A C K Fig.36 Random Read Cycle Timing S T A R T SDA LINE R E A D SLAVE ADDRESS S T O P DATA 1 0 1 0 A2 A1 A0 D7 It is necessary to input “High” at last ACK timing. D0 A C K R A / C W K Fig.37 Current Read Cycle Timing ・Random Read operation allows the Master to access any memory location indicated by word address. ・In cases where the previous operation is Random or Current Read (which includes Sequential Read), the internal address counter is increased by one from the last accessed address (n). Thus Current Read outputs the data of the next word address (n+1). ・If an Acknowledge is detected and no STOP condition is generated by the Master (µ-COM), the device will continue to transmit data. (It can transmit all data (2kbit 256word)) ・If an Acknowledge is not detected, the device will terminate further data transmissions and await a STOP condition before returning to standby mode. ・If an Acknowledge is detected with the "Low" level (not "High" level), the command will become Sequential Read, and the next data will be transmitted. Therefore, the Read command is not terminated. In order to terminate Read input Acknowledge with "High" always, then input a STOP condition. S T A R T SDA L IN E R E A D SLAVE ADDRESS 1 0 1 0 A 2A 1A 0 D A T A (n ) D7 R A / C W K S T O P D A T A (n + x) D0 D7 A C K A C K It is necessary to input “High” at last ACK timing. D0 A C K Fig.38 Sequential Read Cycle Timing （With Current Read） www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 9/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Software Reset Execute software reset in the event that the device is in an unexpected state after power up and/or the command input needs to be reset. Below are three types(Fig.39 –(a), (b), (c)) of software reset: ・During dummy clock, release the SDA BUS (tied to VCC by a pull-up resistor) . ・During this time the device may pull the SDA line Low for Acknowledge or the outputting of read data. ・If the Master sets the SDA line to High, it will conflict with the device output Low, which can cause current overload and result in instantaneous power down, which may damage the device. DUMMY CLOCK×14 SCL 1 2 13 START×2 COMMAND 14 SDA COMMAND Fig.39-(a) DUMMY CLOCK×14 + START+START START 1 SCL START DUMMY CLOCK×9 2 8 9 COMMAND SDA COMMAND Fig.39-(b) START + DUMMY CLOCK×9 + START START×9 SCL 1 3 2 7 8 9 COMMAND SDA COMMAND Fig.39-(c) START×9 * COMMAND starts with start condition. ●Acknowledge polling Since the IC ignores all input commands during the internal write cycle, no ACK signal will be returned. When the Master sends the next command after the Write command, if the device returns an ACK signal it means that the program is completed. No ACK signal indicates that the device is still busy. Using Acknowledge polling decreases the waiting time by tWR=5ms. When operating Write or Current Read after Write, first transmit the Slave address (R/W is"High" or "Low"). After the device returns the ACK signal continue word address input or data output. During the internal write cycle, no ACK will be returned. THE FIRST WRITE COMMAND (ACK=High) S T A R T WRITE COMMAND S T A R T S Ｔ O P SLAVE ADDRESS A C K H S T A R T SLAVE ADDRESS A C K H ・・・ tWR THE SECOND WRITE COMMAND ・・・ S T A R T SLAVE ADDRESS A C K H S T A R T SLAVE ADDRESS tWR A C K L WORD ADDRESS A C K L DATA A C K L S Ｔ O P After the internal write cycle is completed, ACK will be returned (ACK=Low). Then input next Word Address and data. Fig.40 Successive Write Operation By Acknowledge Polling www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 10/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●WP effective timing WP is normally fixed at "H" or "L". However, in case WP needs to be controlled in order to cancel the Write command, pay attention to “WP effective timing” as follows: The Write command is canceled by setting WP to "H" within the WP cancellation effective period. The period from the START condition to the rising edge of the clock (which takes in the data DO - the first byte of the Page Write data) is the ‘invalid cancellation period’. WP input is considered inconsequential during this period. The setup time for the rising edge of the SCL, which takes in DO, must be more than 100ns. The period from the rising edge of SCL (which takes in the data D0) to the end of internal write cycle (tWR) is the ‘effective cancellation period’. When WP is set to "H" during tWR, Write operation is stopped, making it necessary to rewrite the data. It is not necessary to wait for tWR (5ms max.) after stopping the Write command by WP because the device is in standby mode. ・The rising edge of the clock which take in D0 SCL SDA D1 D0 ・The rising edge ・of SDA SCL SDA ACK D0 AN AN ENLARGEMENT SDA S A T SLAVE C WORD A K R ADDRESS L ADDRESS T WP ACK ENLARGEMENT A A C C D7 D6 D2 D5 D1 D0 D3 D4 K K L L DATA A C K L S T O P tWR WP cancellation WP cancellation Stop of the write invalid period effective period operation Data is not No data will be guaranteed Fig.41 WP effective timing ●Command cancellation from the START and STOP conditions Command input is canceled by successive inputs of START and STOP conditions. (Refer to Fig.42) However, during ACK or data output, the device may set the SDA line to Low, making operation of the START and STOP conditions impossible, and thus preventing reset. In this case execute reset by software. (Refer to Fig.39) The internal address counter will not be determined when operating the Cancel command by the START and STOP conditions during Random, Sequential or Current Read. Operate a Random Read in this case. SCL SDA 1 0 1 0 START CONDITION STOP CONDITION Fig.42 Command cancellation by the START and STOP conditions during input of the Slave Address www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 11/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●I/O Circuit ○SDA Pin Pull-up Resistor A pull-up resistor is required because SDA is an NMOS open drain. Determine the resistor value of (RPU) by considering the VIL and IL, and VOL-IOL characteristics. If a large RPU is chosen, the clock frequency needs to be slow. A smaller RPU will result in a larger operating current. ○Maximum RPU The maximum of RPU can be determined by the following factors. ①The SDA rise time determined by RPU and the capacitance of the BUS line(CBUS) must be less than tR. In addition, all other timings must be kept within the AC specifications. ②When the SDA BUS is High, the voltage A at the SDA BUS is determined from the total input leakage(IL) of all devices connected to the BUS. RPU must be higher than the input High level of the microcontroller and the device, including a noise margin 0.2VCC. Microcontroller VCC-ILRPU-0.2 VCC ≧ VIH ∴ R PU ≦ BR34L02FV-W 0.8VCC -VIH IL RPU SDA PIN A Examples: When VCC =3V, IL=10µA, VIH=0.7 VCC IL According to ② RPU IL 0.8×3-0.7×3 ≦ 10×10-6 THE CAPACITANCE OF BUS LINE (CBUS) ≦ 300 ［kΩ］ ○Minimum RPU Fig.43 I/O Circuit The minimum value of RPU is determined by following factors. ①Meets the condition that VOLMAX=0.4V, IOLMAX=3mA when the output is Low. VCC -VOL ≦ IOL R PU VCC -VOL IOL ②VOLMAX=0.4V must be lower than the input Low level of the microcontroller and the EEPROM including the recommended noise margin of 0.1VCC. VOLMAX ≦ VIL-0.1 VCC ∴ RPU ≧ RPU ≧ 3-0.4 3×10 -3 ≧ 867 ［Ω］ VOL=0.4［V］ VIL=0.3×3 =0.9［V］ so that condition ② is met and ○SCL Pin Pull-up Resistor When SCL is controlled by the CMOS output the pull-up resistor at SCL is not required. However, should SCL be set to Hi-Z, connection of a pull-up resistor between SCL and VCC is recommended. Several kΩ are recommended for the pull-up resistor in order to drive the output port of the microcontroller. ●A0, A1, A2, WP Pin connections ○Device Address Pin (A0, A1, A2) connections The status of the device address pins is compared with the device address sent by the Master. One of the devices that is connected to the identical BUS is selected. Pull up or down these pins or connect them to VCC or GND. Pins that are not used as device address (N.C.Pins) may be High, Low, or Hi-Z. ○WP Pin connection The WP input allows or prohibits write operations. When WP is High, only Read is available and Write to all address is prohibited. Both Read and Write are available when WP is Low. In the event that the device is used as a ROM, it is recommended that the WP input be pulled up or connected to VCC. When both READ and WRITE are operated, the WP input must be pulled down or connected to GND or controlled. www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 12/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Microcontroller connection ○Concerning Rs 2 The open drain interface is recommended for the SDA port in the I C BUS. However, if the Tri-state CMOS interface is applied to SDA, insert a series resistor (Rs) between the SDA pin of the device and the pull up resistor RPU is recommended, since it will serve to limit the current between the PMOS of the microcontroller, and the NMOS of the EEPROM. Rs also protects the SDA pin from surges. Therefore, Rs is able to be used though open drain inout of the SDA port. ACK RPU SCL RS SDA 'H'OUTPUT OF CONTROLLER “L” OUTPUT OF EEPROM CONTROLLER The “H” output of controller and the “L” output of EEPROM may cause current overload to SDA line. EEPROM Fig.44 I/O Circuit ○Rs Maximum The maximum value of Rs is determined by following factors. ①SDA rise time determined by RPU and the capacitance value of the BUS line (CBUS) of SDA must be less than tR. In addition, the other timings must be within the timing conditions of the AC. A is determined by RPU, and Rs must be lower than ②When the output from SDA is Low, the voltage of the BUS at ○ the input Low level of the microcontroller, including recommended noise margin (0.1VCC). VCC (VCC-VOL)×RS R PU+R S RPU A RS VOL ∴ RS ≦ IOL BUS CAPACITANCE VIL + VOL+0.1VCC≦VIL V IL -VOL -0.1VCC 1.1VCC-VIL × RPU Examples : When VCC=3V V IL =0.3VCC V OL=0.4V R PU=20kΩ EEPROM CONTROLLER According to ② RS ≦ 0.3×3-0.4-0.1×3 1.1×3-0.3×3 × 20×103 ≦ 1.67［kΩ］ Fig.46 I/O Circuit ○Rs Minimum The minimum value of Rs is determined by the current overload during BUS conflict. Current overload may cause noises in the power line and instantaneous power down. The following conditions must be met, where “I” is the maximum permissible current, which depends on the Vcc line impedance as well as other factors. “I” current must be less than 10mA for EEPROM. Vcc ≦ RS RPU "L" OUTPUT RS ∴ RS ≧ I Vcc I Examples: When VCC=3V, I=10mA "H" OUTPUT MAXIMUM CURRENT CONTROLLER RS ≧ 3 10×10-3 ≧ 300［Ω］ EEPROM Fig.47 I/O Circuit www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 13/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●I2C BUS Input / Output equivalent circuits ○Input (A0,A2,SCL) Fig.48 Input Pin Circuit ○Input / Output (SDA) Fig.49 Input / Output Pin Circuit ○Input (A1) Fig.50 Input Pin Circuit ○Input (WP) Fig.51 Input Pin Circuit www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 14/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Power Supply Notes VCC increases through the low voltage region where the internal circuit of IC and the microcontroller are unstable. In order to prevent malfunction, the IC has P.O.R and LVCC functionality. During power up, ensure that the following conditions are met to guaranty P.O.R. and LVCC operability. 1. "SDA='H'" and "SCL='L' or 'H'". 2. Follow the recommended conditions of tR, tOFF, Vbot so that P.O.R. will be activated during power up. tR VCC Recommended conditions of tR, tOFF, Vbot tOFF tR tOFF Vbot Below 10ms Above 10ms Below 0.3V Below 100ms Above 10ms Below 0.2V Vbot 0 Fig.52 VCC rising wavefrom 3. Prevent SDA and SCL from being "Hi-Z". In case that condition 1. and/or 2. cannot be met, take following actions. A) If unable to keep Condition 1 (SDA is "Low" during power up) →Make sure that SDA and SCL are "High" as in the figure below. VCC tLOW SCL SDA After Vcc becomes stable After Vcc becomes stable tDH tSU:DAT Fig.53 SCL="H" and SDA="L" tSU:DAT Fig.54 SCL="L" and SDA="L" B) If unable to keep Condition 2 →After the power stabilizes, execute software reset. (See page 9,10) C) If unable to keep either Condition 1 or 2 →Follow Instruction A first, then B ●LVCC Circuit The LVCC circuit prevents Write operation at low voltage and prevents inadvertent writing. A voltage below the LVCC voltage (1.2V typ.) prohibits Write operation. ●VCC Noise ○Bypass Capacitor Noise and surges on the power line may cause abnormal function. It is recommended that bypass capacitors (0.1µF) be attached between VCC and GND externally. www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 15/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Notes for Use 1) Descrived numeric values and data are design representative values, and the values are not guaranteed. 2) We believe that application circuit examples are recommendable, however, in actual use, confirm characteristics further sufficiently. In the case of use by changing the fixed number of external parts, make your decision with sufficient margin in consideration of static characteristics and transition characteristics and fluctuations of external parts and our LSI. 3) Absolute maximum ratings If the absolute maximum ratings such as impressed voltage and action temperature range and so forth are exceeded, LSI may be destructed. Do not impress voltage and temperature exceeding the absolute maximum ratings. In the case of fear exceeding the absolute maximum ratings, take physical safety countermeasures such as fuses, and see to it that conditions exceeding the absolute maximum ratings should not be impressed to LSI. 4) GND electric potential Set the voltage of GND terminal lowest at any action condition. Make sure that each terminal voltage is lower than that of GND terminal. 5) Heat design In consideration of permissible dissipation in actual use condition, carry out heat design with sufficient margin. 6) Terminal to terminal short circuit and wrong packaging When to package LSI on to a board, pay sufficient attention to LSI direction and displacement. Wrong packaging may destruct LSI. And in the case of short circuit between LSI terminals and terminals and power source, terminal and GND owing to foreign matter, LSI may be destructed. 7) Use in a strong electromagnetic field may cause malfunction, therfore, evaluate design sufficiently . www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 16/17 2009.04 - Rev.A Technical Note BR34L02FV-W ●Ordering part number B R 3 ROHM type 4 L BUS type Priduct type 34:I2C 0 2 F V Capacity Packagr 02= 2K FV:SSOP-B8 - W E 2 W: Double Cell Packaging and forming specification E2: Embossed tape and reel SSOP-B8 <Tape and Reel information> 3.0 ± 0.2 (MAX 3.35 include BURR) 0.3MIN 4.4±0.2 6.4±0.3 8 76 5 Tape Embossed carrier tape Quantity 2500pcs Direction of feed E2 The direction is the 1pin of product is at the upper left when you hold ( reel on the left hand and you pull out the tape on the right hand ) 1.15±0.1 1 23 4 0.15 ± 0.1 0.1 S 0.1 +0.06 0.22 -0.04 (0.52) 0.08 M 0.65 1pin (Unit : mm) www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. Reel 17/17 Direction of feed ∗ Order quantity needs to be multiple of the minimum quantity. 2009.04 - Rev.A Notice Notes No copying or reproduction of this document, in part or in whole, is permitted without the consent of ROHM Co.,Ltd. The content specified herein is subject to change for improvement without notice. The content specified herein is for the purpose of introducing ROHM's products (hereinafter "Products"). If you wish to use any such Product, please be sure to refer to the specifications, which can be obtained from ROHM upon request. Examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the Products. The peripheral conditions must be taken into account when designing circuits for mass production. Great care was taken in ensuring the accuracy of the information specified in this document. However, should you incur any damage arising from any inaccuracy or misprint of such information, ROHM shall bear no responsibility for such damage. The technical information specified herein is intended only to show the typical functions of and examples of application circuits for the Products. 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Please be sure to implement in your equipment using the Products safety measures to guard against the possibility of physical injury, fire or any other damage caused in the event of the failure of any Product, such as derating, redundancy, fire control and fail-safe designs. ROHM shall bear no responsibility whatsoever for your use of any Product outside of the prescribed scope or not in accordance with the instruction manual. The Products are not designed or manufactured to be used with any equipment, device or system which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injury (such as a medical instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, fuel-controller or other safety device). ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes. If a Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing. If you intend to export or ship overseas any Product or technology specified herein that may be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to obtain a license or permit under the Law. Thank you for your accessing to ROHM product informations. More detail product informations and catalogs are available, please contact us. ROHM Customer Support System http://www.rohm.com/contact/ www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. R0039A