DS2223 Dallas Semiconducotr, DS2223 Datasheet
DS2223
Available stocks
Related parts for DS2223
DS2223 Summary of contents
Page 1
... DESCRIPTION The DS2223 and DS2224 EconoRAMs are fully static, micro–powered, read/write memories in low–cost TO–92 or SOT–223 packages. The DS2223 is orga- nized as a serial 256 x 1 bit static read/write memory. The DS2224’s first 32 bits are lasered with a unique ID code at the time of manufacture; the remaining 224 bits are static read/write memory ...
Page 2
... DS2223/DS2224 OPERATION All communications to and from the EconoRAM are accomplished via a single interface lead. EconoRAM data is read and written through the use of time slots. All data is preceded by a command byte to specify the type of transaction. Once a specific transaction has been initiated, either a read or a write, it must be com- pleted for all memory locations before another transaction can be started ...
Page 3
... RDV 60 s < t SLOT RESISTOR 1 s < t LOWR 0 < t MASTER RELEASE 1 s < t REC DS2223/DS2224 RDV t t SLOT REC DS2223/DS2224 60 s < SLOT < LOW1 < REC t REC t SLOT t LOW0 < t < SLOT < t SLOT REC t RELEASE < < < < DS2223/DS2224 080598 3/10 ...
Page 4
... DS2223/DS2224 COMMAND WORD Figure 4 MSB W/R W/R W/R W/R ALL 1s – WRITE ANY 0 – READ READ/WRITE TRANSACTION Figure 5 LSB DS2223 COMMAND WORD DS2224 COMMAND WORD READ/WRITE FLOW RECEIVE COMMAND WORD (RESET ADDRESS POINTER) READ/WRITE DATA BIT AND INCREMENT ADDRESS POINTER 264–BIT TRANSACTION HOLD ADDRESS POINTER ...
Page 5
... TYPICAL CURRENT CONSUMPTION VS. BIT RATE Figure + 100 bps 100 bps TYPICAL LEAKAGE CURRENT VS. TEMPERATURE Figure 7 15 4.0V CC 12.0 9.0 6.0 3.0 0.0 –10 0 +10 DS2223/DS2224 129 pC/BIT 1 kbps 10 kbps 100 kbps BIT RATE +20 +30 +40 +50 +60 +70 TEMPERATURE (DEG. C) 080598 5/10 ...
Page 6
... DS2223/DS2224 1–WIRE INTERFACE The 1–Wire interface has only a single line by definition important that host and EconoRAM be able to drive it at the appropriate time. The EconoRAM is an open drain part with an internal circuit equivalent to that shown in Figure 8. The host can be the same equivalent circuit bidirectional pin is not available, separate output and input pins can be tied together ...
Page 7
... SUGGESTED CIRCUIT Figure Econo Memory GND ICC VS. DQ VOLTAGE Figure 10 SUPPLY CURRENT 400 ( A) 200 PIN VOLTAGE DS2223/DS2224 CAP + C1 CR1 V = +5V CC Room Temperature SUPPLY CURRENT < 080598 7/10 ...
Page 8
... DS2223/DS2224 DATA RETENTION TIME VS. CAPACITANCE Figure 11 CAPACITANCE 10K ( F) 1K 100 TIME (hours) Using Battery Backup 14 mA–Hr => 144 million transactions 2 DATA DS2223 PIN DS2224 080598 8/10 Initial V Voltage 3 5.0 CC 100 1K 10K 3 + 1.5V EVEREADY NO. 321 1 ...
Page 9
... V V 5.5 V PUP 500 (– + =1.4V CC MIN TYP MAX UNITS –0.5 0.2 V 1 5.5 V PUP 500 DS2223/DS2224 NOTES 1 1 NOTES 10%) NOTES 080598 9/10 ...
Page 10
... DS2223/DS2224 AC ELECTRICAL CHARACTERISTICS PARAMETER SYMBOL Time Slot t SLOT Read Data Valid t RDV Release Time t RELEASE Write 1 Low Time t LOW1 Write 0 Low Time t LOW0 Data Setup Time t SU Recovery Time t REC AC ELECTRICAL CHARACTERISTICS PARAMETER SYMBOL Time Slot t SLOT Read Data Valid t RDV ...