Rainbow-electronics DS2740 Manual de usuario

1 of 15 033103FEATURES§ 15-Bit Bidirectional Current Measurement(DS2740)§ 1.56mV LSB and ±51.2mV DynamicRange§ 78mA LSB and ±2.56A DynamicRange wit

DS274010 of 15Skip Net Address [CCh]. This command saves time when there is only one DS2740 on the bus byallowing the bus master to issue a function c

DS274011 of 15Figure 10. NET ADDRESS COMMAND FLOW CHARTMASTER TxRESET PULSEDS2740 TxPRESENCE PULSEMASTER Tx NETADDRESSCOMMAND55hMATCH33h / 39hREADF0hS

DS274012 of 15Table 4. FUNCTION COMMANDSCOMMAND DESCRIPTIONCOMMANDPROTOCOLBUS STATEAFTER COMMANDPROTOCOLBUS DATARead DataReads data frommemory startin

DS274013 of 15READ-TIME SLOTSA read-time slot is initiated when the bus master pulls the 1-Wire bus line from a logic-high level to alogic-low level.

DS274014 of 15ABSOLUTE MAXIMUM RATINGS*Voltage on VDD, DQ, IS1, IS2, PIO, Relative to VSS-0.3V to +6VVoltage on SNS, Relative to VSS-0.3V to +6VOperat

DS274015 of 15Input Logic Low: DQ,PIOVIL(Note 1) 0.6 VOutput Logic Low:DQ, PIOVOLIOL = 4mA (Note 1) 0.4 VDQ, PIO InputPulldown CurrentIPDVDD = 4.2V,VD

DS27402 of 15Table 1. ORDERING INFORMATIONPART MARKING PIN-PACKAGEDS2740UDS274015-Bit Current Resolution, mMAXDS2740U/T&RDS274015-Bit Current Reso

DS27403 of 15Table 2. DETAILED PIN DESCRIPTIONPIN SYMBOL DESCRIPTIONOVD 11-Wire Bus Speed Control. Input logic level selects the speed of the 1-Wire b

DS27404 of 15POWER MODESThe DS2740 has two power modes: active and sleep. While in active mode, the DS2740 operates as ahigh-precision coulomb counter

DS27405 of 15CURRENT RESOLUTION (1 LSB)RSNSPARTCONVERSIONTIMEVIS1 - VIS220mW 15mW 10mW 5mWDS27403.515s1.5625mV 78.13mA 104.2mA 156.3mA 312.5mADS2740B0

DS27406 of 15ACR RANGERSNSPARTVIS1- VIS220mW 15mW 10mW 5mW DS2740 DS2740B±204.8mVh ±10.24Ah ±13.65Ah ±20.48Ah ±40.96AhMEMORYThe DS2740 has memory sp

DS27407 of 15SPECIAL FEATURE REGISTERThe format of the special feature register is shown in Figure 6. The function of each bit is described indetail i

DS27408 of 15CRC is available in Application Note 27, Understanding and Using Cyclic Redundancy Checks withDallas Semiconductor Touch Memory Products.

DS27409 of 15Figure 9. 1-WIRE BUS INTERFACE CIRCUITRYTRANSACTION SEQUENCEThe protocol for accessing the DS2740 through the 1-Wire port is as follows:§