SP3224ECA-L/TR [EXAR]
Line Transceiver, 2 Driver, PDSO20;
| 型号： | SP3224ECA-L/TR |
| 厂家： | 
EXAR CORPORATION |
| 描述： | Line Transceiver, 2 Driver, PDSO20 驱动 光电二极管 接口集成电路 驱动器 |
| 文件： | 总23页 (文件大小：4179K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
SP3224E-SP3227E
®
3.0V to 5.5V RS-232 Transceivers with Auto On-Line Plus
FEATURES
■ꢀ 15kVꢀESDꢀprotectedꢀRS-232ꢀI/Oꢀpins
■ꢀ AutoꢀOn-line ꢀPlusꢀautomaticꢀpowerꢀsavingꢀmodeꢀ
■ꢀ MeetsꢀtrueꢀEIA/TIA-232-Fꢀstandardsꢀfromꢀ+3.0Vꢀtoꢀ
+5.5Vꢀpowerꢀsupply.
SHUTDOWN
READY
C1+
20
19
18
1
2
3
4
5
6
7
8
9
V
CC
®
GND
OUT
V+
T
1
C1-
17
SP3224E
SP3225E
R
1
IN
C2+
C2-
16
15
14
13
12
11
■ꢀ AdheresꢀtoꢀEIA/TIA-562ꢀforꢀinteroperabilityꢀwithꢀ
R
1
OUT
ꢀ
EIA/TIA-232ꢀdownꢀtoꢀaꢀ+2.7Vꢀsupplyꢀvoltage
■ꢀ Regulatedꢀchargeꢀpumpꢀyieldsꢀstable
RS-232ꢀoutputsꢀ
ONLINE
IN
IN
STATUS
V-
T
1
T
2
OUT
ꢀ
T
2
R
2
IN
■ꢀ Drop-inꢀreplacementꢀtoꢀMAX3224,ꢀICL3224,ꢀ
MAX3225,ꢀICL3225,ꢀMAX3226,ꢀICL3226,ꢀ
MAX3227ꢀandꢀICL3227
R
2
OUT
10
TyPICAL APPLICATIONS
■ꢀ Diagnostic/Serialꢀportsꢀon
■ꢀ SP3224EꢀandꢀSP3226EꢀreducedꢀEMIꢀwithꢀaꢀslewꢀ
rateꢀcontrolledꢀ250kbpsꢀdataꢀrate
■ꢀ SP3225EꢀandꢀSP3227E-ꢀhighꢀspeedꢀdataꢀrateꢀofꢀ
1ꢀMbps.ꢀ
■ꢀ AvailableꢀinꢀRoHSꢀcompliant,ꢀLeadꢀFree
ꢀ embeddedꢀapplications
■ꢀ HandheldꢀTestꢀEquipment
■ꢀ PCꢀrelatedꢀPeripheralsꢀandꢀ
ꢀ
Packaging
ꢀ
Equipment
■ꢀ BatteryꢀPoweredꢀEquipment
■ꢀ Point-of-saleꢀEquipment
■ꢀ Set-topꢀBox
DESCRIPTION
TheꢀSP3224E/3225Eꢀareꢀ2-driver/2-receiverꢀdevicesꢀandꢀtheꢀSP3226E/SP3227Eꢀareꢀ1-
driver/1-receiverꢀdevices.ꢀAllꢀareꢀidealꢀforꢀcomputerꢀperipherals,ꢀpoint-of-saleꢀequipment,ꢀ
consumerꢀ andꢀ embeddedꢀ applications.ꢀ Theseꢀ devicesꢀ useꢀ anꢀ internalꢀ high-efficiency,ꢀ
charge-pumpꢀ powerꢀ supplyꢀ thatꢀ requiresꢀ onlyꢀ 0.1μFꢀ capacitorsꢀ inꢀ 3.3Vꢀ operation.ꢀThisꢀ
chargeꢀpumpꢀandꢀExar’sꢀdriverꢀarchitectureꢀallowꢀitꢀtoꢀdeliverꢀcompliantꢀRS-232ꢀperfor-
manceꢀfromꢀaꢀsingleꢀpowerꢀsupplyꢀrangingꢀfromꢀ+3.0Vꢀtoꢀ+5.5V.ꢀꢀAtꢀvoltagesꢀbetweenꢀ2.7Vꢀ
andꢀ3.0VꢀtheꢀdriverꢀoutputsꢀareꢀcompliantꢀwithꢀRS-562ꢀandꢀcanꢀinterfaceꢀtoꢀRS-232ꢀoverꢀ
shortꢀcables.
®
TheꢀAutoꢀOn-line ꢀPlusꢀfeatureꢀallowsꢀtheꢀdeviceꢀtoꢀautomaticallyꢀ“wake-up”ꢀduringꢀaꢀshut-
downꢀstateꢀuponꢀdetectingꢀactivityꢀandꢀtoꢀenterꢀaꢀlowꢀpowerꢀshutdownꢀifꢀidle.ꢀꢀThisꢀpowerꢀ
savingꢀfeatureꢀfunctionsꢀwithoutꢀsystemꢀinterventionꢀorꢀmodificationsꢀtoꢀsoftwareꢀorꢀdriv-
ers.
SELECTION TABLE
ꢀꢀꢀꢀꢀAllꢀdevicesꢀfeatureꢀ3.0Vꢀtoꢀ5.5Vꢀpowerꢀsupply,ꢀ4ꢀsmallꢀchargeꢀpumpꢀcapacitors,ꢀandꢀ15kVꢀESDꢀ
protection.
Device
DataꢀRateꢀ(bps)
No.ꢀofꢀ
READYꢀpin
Low-PowerꢀShutdown
Package
Drivers/Receivers
®
SP3224E
SP3225E
SP3226E
SP3227E
250k
1M
2/2
2/2
1/1
1/1
Yes
Yes
Yes
Yes
AutoꢀOn-Line ꢀPlus
20ꢀSSOP/TSSOP
20ꢀSSOP/TSSOP
16ꢀSSOP/TSSOP
16ꢀSSOP/TSSOP
®
AutoꢀOn-Line ꢀPlus
®
250k
1M
AutoꢀOn-Line ꢀPlus
®
AutoꢀOn-Line ꢀPlus
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ
ABSOLUTE MAXIMUM RATINGS
SupplyꢀVoltageꢀ(Vcc).................................................-0.3Vꢀtoꢀ+ꢀ6.0V
V+ꢀ(Noteꢀ1)................................................................-0.3Vꢀtoꢀ+ꢀ7.0V
V-ꢀ(Noteꢀ1).................................................................+0.3Vꢀtoꢀ-ꢀ7.0V
|V+|ꢀ+ꢀ|V-|ꢀ.................................................................................+13V
InputꢀvoltageꢀatꢀTTLꢀinputꢀpinsꢀ............................-0.3VꢀtoꢀVcc+0.3V
RxIN.........................................................................................ꢀ±16V
Driverꢀoutputꢀ(fromꢀGround)..................................................ꢀ±13.2V
RxOUT,ꢀSTATUS..................................................-0.3VꢀtoꢀVcc+0.3V
ShortꢀCircuitꢀDuration,ꢀTxOUTꢀtoꢀGND,.ꢀContinuous
Maximumꢀjunctionꢀtemperature.....................................................150°C
Thermal Derating, Junction to Ambient
SSOP20..............................................................................θJA =83°C/W
TSSOP20.......................................................................θJA =110.7°C/W
SSOP16..............................................................................θJA =87°C/W
TSSOP16.......................................................................θJA =100.4°C/W
(Oneꢀoutputꢀatꢀaꢀtimeꢀmaximum)
StorageꢀTemperature...............................................-65°Cꢀtoꢀ+150°C
OperatingꢀTemperatureꢀSP322XECX...........................0°Cꢀtoꢀ+70°Cꢀ
OperatingꢀTemperatureꢀSP322XEEX........................-40°Cꢀtoꢀ+85°Cꢀ
LeadꢀTemperatureꢀ(soldering,ꢀ10s).......................................ꢀ+300°C
Theseꢀareꢀstressꢀratingsꢀonlyꢀandꢀfunctionalꢀoperationꢀofꢀtheꢀdeviceꢀatꢀ
theseꢀratingsꢀorꢀanyꢀotherꢀaboveꢀthoseꢀindicatedꢀinꢀtheꢀoperationꢀsectionsꢀ
ofꢀtheꢀspecificationsꢀbelowꢀisꢀnotꢀimplied.ꢀExposureꢀtoꢀabsoluteꢀmaximumꢀ
ratingꢀ conditionsꢀ forꢀ extendedꢀ periodsꢀ ofꢀ timeꢀ mayꢀ affectꢀ reliability.
Noteꢀ1:ꢀV+ꢀandꢀV-ꢀcanꢀhaveꢀmaximumꢀmagnitudesꢀofꢀ7V,ꢀbutꢀtheirꢀ
absoluteꢀdifferenceꢀcannotꢀexceedꢀ13V.
ELECTRICAL SPECIFICATIONS
UnlessꢀotherwiseꢀnotedꢀVCCꢀ=ꢀ+3.0Vꢀtoꢀ+5.5V,ꢀTAMBꢀ=ꢀTMINꢀtoꢀTMAX,.ꢀTypicalꢀvaluesꢀareꢀatꢀTAMBꢀ=ꢀ+25°C.ꢀ
C1–C4ꢀ=ꢀ0.1μFꢀtestedꢀatꢀ3.3Vꢀ±10%.ꢀC1=0.047μFꢀC2–C4ꢀ=ꢀ0.33μFꢀtestedꢀatꢀ5Vꢀ±10%.
Parameters
DC Characteristics
Sꢀmb
Test Conditions
Min.
Tꢀp.
Max.
Unit
Receiversꢀidle,ꢀTxINꢀ=ꢀVccꢀorꢀGND,ꢀ
SupplyꢀCurrent,ꢀAutoꢀOn-Line®ꢀPlus
Icc3
ꢀ
ꢀ0
μA
ONLINEꢀ=ꢀGND,ꢀSHUTDOWN =ꢀVcc
Note 2
SupplyꢀCurrent,ꢀShutdown
SupplyꢀCurrent,ꢀActiveꢀ
Icc2
Iccꢀ
SHUTDOWNꢀ=ꢀGND
ꢀ
ꢀ0
μA
ONLINE = SHUTDOWNꢀ=ꢀVcc,ꢀNoꢀLoad
ꢀ.5
3.0
mA
ONLINE = SHUTDOWNꢀ=ꢀVcc=3.3V,ꢀ
NoꢀLoad
SupplyꢀCurrent,ꢀActiveꢀ
Iccꢀ
0.7
2.0
mA
Driver Input and Logic Input Pins
Vih
Vih
Vil
Vccꢀ=ꢀ3.3V
Vccꢀ=ꢀ5.0V
2
High
2.4
LogicꢀInputꢀ
Voltageꢀ
V
Low
0.8
LogicꢀThreshold
LogicꢀInputꢀLeakageꢀCurrent
LogicꢀInputꢀHysteresis
Vt
ꢀ.5
0.05
ꢀ00
Iil
±1.0
μA
Vhys
mV
Receiver Outputs and STATUS Output
ReceiverꢀOutputꢀVoltageꢀLow
Vol
Voh
ꢀIout = -ꢀ.6mA
ꢀIout = ꢀmA
0.4
V
V
Vccꢀ
- 0.6
ReceiverꢀOutputꢀVoltageꢀHigh
Noteꢀ2:ꢀCharacterized,ꢀnotꢀ100%ꢀtested.
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
2
ELECTRICAL SPECIFICATIONS
UnlessꢀotherwiseꢀnotedꢀVCCꢀ=ꢀ+3.0Vꢀtoꢀ+5.5V,ꢀTAMBꢀ=ꢀTMINꢀtoꢀTMAX,.ꢀTypicalꢀvaluesꢀareꢀatꢀTAMBꢀ=ꢀ+25°C.ꢀ
C1–C4ꢀ=ꢀ0.1μFꢀtestedꢀatꢀ3.3Vꢀ±10%.ꢀC1=0.047μFꢀC2–C4ꢀ=ꢀ0.33μFꢀtestedꢀatꢀ5Vꢀ±10%.
Parameters
Sꢀmb
Test Conditions
Min.
Tꢀp.
Max.
Driver Outputs
OutputꢀVoltageꢀSwingꢀ
Vo
Outputꢀloadꢀ=ꢀ3kΩꢀtoꢀGNDꢀ
Outputꢀloadꢀ=ꢀOpenꢀCircuit
Voutꢀ=ꢀ0V
±5.0
±6.0
V
±15.0
±60
ShortꢀCircuitꢀCurrent
Power-OffꢀImpedance
mA
Vcc=V+ꢀ=ꢀV-ꢀ=ꢀ0
300
10M
Ω
transmitterꢀoutputs=ꢀ±2V
OutputꢀLeakageꢀCurrent
Vccꢀ=ꢀ0ꢀorꢀ3Vꢀtoꢀ3.3V,ꢀVout
±25
μA
=ꢀ±12V,ꢀDriversꢀdisabled
Receiver Inputs
InputꢀVoltageꢀRange
InputꢀThresholdꢀLow
-ꢀ5
0.6
0.8
ꢀ5
V
V
Vccꢀ=ꢀ3.3V
Vccꢀ=ꢀ5.0V
Vccꢀ=ꢀ3.3V
Vccꢀ=ꢀ5.0V
ꢀ.2
ꢀ.5
ꢀ.5
ꢀ.8
500
5
InputꢀThresholdꢀHigh
2.4
2.4
V
InputꢀHysteresis
mV
kΩ
InputꢀResistance
3
7
ESD Protection
ESDꢀProtectionꢀforꢀR_In,ꢀT_Outꢀpins
HumanꢀBodyꢀModel
HumanꢀBodyꢀModel
±15
±2
kV
kV
AllꢀOtherꢀPins
Auto On-line® Plus (ONLINE = GND, SHUTDOWN = Vcc)
RxꢀInputꢀThresholdꢀtoꢀSTATUSꢀoutputꢀhigh
±2.7
V
V
RxꢀInputꢀThresholdꢀtoꢀSTATUSꢀoutputꢀlow
±0.3
ThresholdꢀtoꢀSTATUSꢀhigh
tsth
tstl
0.5
30
μs
μs
μs
sec
ThresholdꢀtoꢀSTATUSꢀlow
RxꢀorꢀTxꢀtransitionꢀtoꢀdriversꢀenabled
LastꢀRxꢀorꢀTxꢀtransitionꢀtoꢀdriversꢀdisabled
tonline
toffline
Note 3
ꢀ00
30
Note 2, 3
ꢀ5
60
Noteꢀ3:ꢀAꢀtransmitter/receiverꢀedgeꢀisꢀdefinedꢀasꢀaꢀtransitionꢀthroughꢀinputꢀlogicꢀthresholds.
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
3
TIMING CHARACTERISTICS
UnlessꢀotherwiseꢀnotedꢀVccꢀ=ꢀ+3.0Vꢀtoꢀ+5.5V,ꢀTAmbꢀ=ꢀTminꢀtoꢀTmAx,.ꢀTypicalꢀvaluesꢀareꢀatꢀTAmbꢀ=ꢀ+25°C.ꢀC1–C4ꢀ=ꢀ
0.1μFꢀtestedꢀatꢀ3.3Vꢀ±10%.ꢀC1=0.047μFꢀC2–C4ꢀ=ꢀ0.33μFꢀtestedꢀatꢀ5Vꢀ±10%
Parameters
Sꢀmbol
Test Conditions
Min.
250
4
Tꢀp.
Max.
Unit
kbps
V/μs
SP3224E and SP3226E
MaximumꢀDataꢀRate
RLꢀ=ꢀ3kΩ,ꢀCLꢀ=ꢀ1000pF.ꢀOneꢀ
transmitterꢀswitching.ꢀ
ꢀMeasurementꢀtakenꢀfrom
+3.0Vꢀtoꢀ-3.0Vꢀorꢀ-3.0Vꢀtoꢀ+3.0V,ꢀ
TAmb = 25°c
Transitionꢀ-Regionꢀ
SlewꢀRate
30
RLꢀ=ꢀ3kΩꢀtoꢀ7kΩ,ꢀꢀ
CL = ꢀ50pF to ꢀ000pF
ReceiverꢀPropagationꢀ
Delay
R_INꢀtoꢀR_OUT,
CL = ꢀ50pF
tRPHL , tRPLH
0.22
0.2
µs
µs
ReceiverꢀOutputꢀ
EnableꢀTime
tRZH , tRZL
RLꢀ=ꢀ3kΩ,ꢀCL = ꢀ50pF
|tPHL - tPLH|ꢀatꢀ1.5V
2
2
ReceiverꢀOutputꢀ
DisableꢀTime
tRHZ , tRLZ
0.2
µs
ns
ReceiverꢀSkew
200
Parameters
Sꢀmbol
Test Conditions
Min.
Tꢀp.
Max.
Unit
SP3225E and SP3227E
RLꢀ=ꢀ3kΩ,ꢀCLꢀ=ꢀ250pF.ꢀOneꢀ
transmitterꢀSwitching
ꢀ000
500
kbps
kbps
MaximumꢀDataꢀRate
RLꢀ=ꢀ3kΩ,ꢀCLꢀ=ꢀ1000pF.ꢀOneꢀ
transmitterꢀSwitching
Measurementꢀtakenꢀfromꢀ+3.0Vꢀ
toꢀ-3.0Vꢀorꢀ-3.0Vꢀtoꢀ+3.0V,ꢀꢀ
TAmb=25°C
InstantaneousꢀSlewꢀ
Rate
24
ꢀ50
V/μs
RLꢀ=ꢀ3kΩꢀtoꢀ7kΩ,ꢀꢀ
CL = ꢀ50pF to 250pF
ꢀatꢀzeroꢀcrossing
DriverꢀSkew
|tDPHL - tDPLH
|
75
ns
µs
ReceiverꢀPropagationꢀ
Delay
tRPHL , tRPLH
tRZH , tRZL
tRHZ , tRLZ
R_INꢀtoꢀR_OUT,ꢀCL = ꢀ50pF
0.20
ReceiverꢀOutputꢀ
EnableꢀTime
0.3
2
2
µs
ReceiverꢀOutputꢀ
DisableꢀTime
0.2
80
µs
ns
ReceiverꢀSkew
|tPHL - tPLH
|
ꢀatꢀ1.5V
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
4
TyPICAL PERFORMANCE CHARACTERISTICS:CURVES
1.6
1.4
1.2
1
2.5
2
1.5
0.8
0.6
0.4
1
0.5
TxIn to RxOut Propagation Delay (us)
0.2
TxIn to RxOut Propagation Delay (us)
0
0
0
1000
2000
3000
4000
5000
0
1000
2000
3000
4000
5000
Load Capacitance (pF)
Load Capacitance (pF)
SP3225E/SP3227EꢀTransmitterꢀInputꢀꢀtoꢀ
ReceiverꢀOutputꢀPropagationꢀDelayꢀvs.ꢀ
LoadꢀCapacitance
SP3224E/SP3226EꢀTransmitterꢀInputꢀꢀtoꢀ
ReceiverꢀOutputꢀPropagationꢀDelayꢀvs.ꢀ
LoadꢀCapacitance
45
40
30
25
20
35
SRpos
30
SRavg
SRneg
25
SRneg
15
20
15
10
SRavg
10
SRpos
5
Transmitter Output Slew Rate (V/us)
5
Transmitter Output Slew Rate (V/us)
0
0
0
1000
2000
3000
4000
5000
0
1000
2000
3000
4000
5000
Load Capacitance (pF)
Load Capacitance (pF)
SP3225E/SP3227EꢀTransmitterꢀOutputꢀ
SlewꢀRateꢀvs.ꢀLoadꢀCapacitance
SP3224E/SP3226EꢀTransmitterꢀOutputꢀ
SlewꢀRateꢀvs.ꢀLoadꢀCapacitance
6
6
V+
V+
4
4
2
2
0
0
-2
-2
Trasmitter Output Voltage (V)
ransmitter Output Voltage (V)
-4
-4
V-
V-
-6
-6
0
1000
2000
3000
4000
5000
0
1000
2000
3000
4000
5000
Load Capacitance (pF)
Load Capacitance (pF)
SP3224E/SP3226EꢀTransmitterꢀOutputꢀ
Voltageꢀvs.ꢀLoadꢀCapacitance
SP3225E/SP3227EꢀTransmitterꢀOutputꢀ
Voltage
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
5
TyPICAL PERFORMANCE CHARACTERISTICS:CURVES
250
200
150
100
SP3225, 1Mbps
SP3224, 250kbps
ransmitter Skew (ns)
50
0
0
500
1000
1500
2000
2500
3000
3500
Load Capacitance (pF)
DriverꢀSkewꢀ
vs.ꢀLoadꢀCapacitance
30
25
20
15
10
SP3225, 1Mbps
SP3227
SP3224, 250kbps
SP3226
upply Current (mA)
5
0
0
1000
2000
3000
4000
5000
Load Capacitance (pF)
ꢀSupplyꢀCurrentꢀ
vs.ꢀLoadꢀCapacitance
Charge Pump Turn-on Time versus Temperature
85
80
75
70
65
60
Charge Pump Turn-on Time (us)
55
50
-55
-30
-5
20
45
70
95
Temperature (C)
ChargeꢀPumpꢀTurn-OnꢀTime
vs.ꢀTemperature
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
6
TyPICAL PERFORMANCE CHARACTERISTICS: SCOPE SHOTS
SP3224E/SP3226EꢀWaveformsꢀ
forꢀ250kbpsꢀClockꢀRate,ꢀRL=3kΩ,ꢀ
CL=1000pF
SP3224E/SP3226EꢀChargeꢀPumpꢀ
IntoꢀShutdown
SP3224E/SP3226EꢀWaveformsꢀ
forꢀ250kbpsꢀClockꢀRate,ꢀRL=3kΩ,ꢀ
CL=4700pF
SP3224E/SP3226EꢀChargeꢀPumpꢀ
PowerꢀOnꢀTime,ꢀVcc=3.3V
SP3224E/SP3226EꢀChargeꢀPumpꢀ
OutꢀofꢀShutdown
SP3224E/SP3226EꢀChargeꢀPumpꢀ
Waveformsꢀforꢀ250kbpꢀClockꢀRate
AllꢀChargeꢀPumpꢀwaveformsꢀuseꢀchargeꢀpumpꢀcapacitorꢀvaluesꢀC1-C4ꢀ=ꢀ0.1µFꢀ
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
7
TyPICAL PERFORMANCE CHARACTERISTICS: SCOPE SHOTS
SP3225E/SP3227EꢀWaveformsꢀforꢀ
1MbpsꢀClockꢀRate,ꢀRL=3KΩ,ꢀ
CL=250pF
SP3224E/SP3226EꢀC2+ꢀChargeꢀ
PumpꢀWaveforms,ꢀVcc=3.3V,ꢀAllꢀ
Channelsꢀswitching
SP3225E/SP3227EꢀWaveformsꢀ
forꢀ1MbpsꢀClockꢀRate,ꢀRL=3KΩ,ꢀ
CL=1000pF
SP3224E/SP3226EꢀC2+ꢀCharge
ꢀPumpꢀWaveforms,ꢀVcc=5V,ꢀ
AllꢀChannelsꢀswitching
SP3225E/SP3227EꢀWaveformsꢀ
forꢀ1MbpsꢀClockꢀRate,ꢀRL=3KΩ,ꢀ
CL=50pF
SP3225E/SP3227EꢀCharge
ꢀꢀꢀꢀPumpꢀOutꢀofꢀShutdown
AllꢀChargeꢀPumpꢀwaveformsꢀuseꢀchargeꢀpumpꢀcapacitorꢀvaluesꢀC1-C4ꢀ=ꢀ0.1µFꢀ
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
8
TyPICAL PERFORMANCE CHARACTERISTICS
SP3225E/SP3227EꢀChargeꢀPump
ꢀIntoꢀShutdown
SP3225E/SP3227EꢀChargeꢀPumpꢀ
Waveforms,ꢀVcc=3.3V,ꢀAllꢀChan-
nelꢀSwitching
SP3225E/SP3227EꢀChargeꢀPumpꢀ
Waveforms,ꢀVcc=5V,ꢀAllꢀChannelꢀ
Switching
SP3225E/SP3227EꢀChargeꢀPumpꢀ
PowerꢀOnꢀTime,ꢀVcc=3.3V
SP3225E/SP3227EꢀChargeꢀPumpꢀ
Waveformsꢀforꢀ1MbpsꢀClockꢀRate
AllꢀChargeꢀPumpꢀwaveformsꢀuseꢀchargeꢀpumpꢀcapacitorꢀvaluesꢀC1-C4ꢀ=ꢀ0.1µFꢀ
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
9
CHARACTERIzATION CIRCUITS AND WAVEFORMS
3V
Input
RS-232
0V
Output
Generator
50Ω
(see note B)
tTHL
tTLH
CL
RL
(see note A)
VOH
VOL
3V
-3V
3V
-3V
3V
Output
SHUTDOWN
6V
SR=
tTHL or tTLH
TEST CIRCUIT
VOLTAGE WAVEFORMS
NOTES A. CL includes probe and jig capacitance
B. The pulse generator has the following characteristics: PRR= 250kbit/s, Zo=50Ω, 50% duty cycle, t ≤10ns, t ≤10ns
r
f
Figure 1. Driver Slew Rate
3V
0V
Input
1.5V
1.5V
RS-232
Output
Generator
50Ω
(see note B)
tDPLH
CL
(see note A)
tDPHL
RL
VOH
VOL
50%
3V
Output
50%
SHUTDOWN
Skew= ItDPHL- tDPLH
I
TEST CIRCUIT
VOLTAGE WAVEFORMS
NOTES A. CL includes probe and jig capacitance
B. The pulse generator has the following characteristics: PRR= 250kbit/s, Zo=50Ω, 50% duty cycle, t ≤10ns, t ≤10ns
r
f
Figure 2. Driver Propagation and Skew
3V or 0V
ONLINE
3V
0V
Input
1.5V
1.5V
RS-232
Output
Generator
50Ω
tRPHL
(see note B)
tRPLH
CL
(see note A)
VOH
VOL
50%
3V
Output
50%
SHUTDOWN
TEST CIRCUIT
VOLTAGE WAVEFORMS
Skew= ItRPHL- tRPLH
I
NOTES A. CL includes probe and jig capacitance
B. The pulse generator has the following characteristics: PRR= 250kbit/s, Zo=50Ω, 50% duty cycle, t ≤10ns, t ≤10ns
r
f
Figure 3. Receiver Propagation Delay and Skew
3V
0V
Input
1.5V
1.5V
VCC
S1
GND
3V or 0V
ONLINE
tPHZ
tPZH
RL
(51 at GND)
Output
3V or 0V
VOH
Output
0.3V
50%
CL
(see note A)
SHUTDOWN
50Ω
tPZL
tPLZ
(51 at VCC)
(S1 at VCC)
Generator
(See Note B)
0.3V
Output
50%
VOLTAGE WAVEFORMS
VOL
TEST CIRCUIT
NOTES: A CL includes probe and jig capacitance
B. The pulse generator has the folowing characteristics Zo=50Ω, 50% duty cycle, t ≤10ns, t ≤10ns
r
f
C. tPLZ and tPHZ are the same as tdis
D. tPZL and tPZH are the same as ten
Figure 4. Receiver Enable and Disable Times
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ0
THEORy OF OPERATION
ratesꢀfullyꢀloadedꢀwithꢀ3KΩꢀinꢀparallelꢀwithꢀ
1000pFꢀ (SP3224E/SP3226E),ꢀ orꢀ 3KΩꢀ inꢀ
parallelꢀ withꢀ 250pFꢀ (SP3225E/SP3227E)ꢀ
ensuringꢀcompatibilityꢀwithꢀPC-to-PCꢀcom-
municationꢀsoftware.ꢀTheꢀslewꢀrateꢀofꢀtheꢀ
driverꢀoutputꢀonꢀtheꢀSP3224E/SP3226Eꢀisꢀ
internallyꢀlimitedꢀtoꢀaꢀmaximumꢀofꢀ30V/μsꢀ
inꢀ orderꢀ toꢀ meetꢀ theꢀ EIAꢀ standardsꢀ (EIAꢀ
RS-232Dꢀ 2.1.7,ꢀ Paragraphꢀ 5).ꢀTheꢀ Slewꢀ
RateꢀofꢀSP3225E/SP3227Eꢀisꢀnotꢀlimitedꢀ
toꢀenableꢀhigherꢀspeedꢀdataꢀtransfers.ꢀTheꢀ
transitionꢀofꢀtheꢀloadedꢀoutputꢀfromꢀHIGHꢀ
toꢀLOWꢀalsoꢀmeetsꢀtheꢀmonotonicꢀsignalꢀ
transitionꢀꢀrequirementsꢀofꢀtheꢀstandard.
Description
TheꢀSP3224EꢀandꢀSP3225Eꢀareꢀ2-driver/ꢀ
2-receiverꢀ devices.ꢀ Theꢀ SP3226Eꢀ andꢀ
SP3227Eꢀ areꢀ 1-driver/1-receiverꢀ devices.ꢀ
Allꢀareꢀidealꢀforꢀserialꢀportsꢀinꢀembedded,ꢀ
consumer,ꢀ portable,ꢀ orꢀ handheldꢀ applica-
tions.ꢀTheꢀtransceiversꢀmeetꢀtheꢀEIA/TIA-
232ꢀ andꢀ ITU-Tꢀ V.28/V.24ꢀ communicationꢀ
protocolsꢀforꢀreliableꢀserialꢀcommunication.ꢀ
TheꢀdevicesꢀfeatureꢀExar’sꢀproprietaryꢀandꢀ
patentedꢀ(U.S.ꢀ5,306,954)ꢀon-boardꢀchargeꢀ
pumpꢀ circuitryꢀ thatꢀ generatesꢀ ±5.5Vꢀ RS-
232ꢀvoltageꢀlevelsꢀfromꢀaꢀsingleꢀ+3.0Vꢀtoꢀ
+5.5Vꢀpowerꢀsupply.
Theꢀ SP3224E-SP3227Eꢀ areꢀ idealꢀ choic-
Receivers
esꢀ forꢀ powerꢀ sensitiveꢀ designs.ꢀ Withꢀ theꢀ
TheꢀreceiversꢀconvertꢀEIA/TIA-232ꢀsignalꢀ
levelsꢀ toꢀ TTLꢀ orꢀ CMOSꢀ logicꢀ outputꢀ lev-
els.ꢀꢀReceiversꢀremainꢀactiveꢀduringꢀdeviceꢀ
shutdown.ꢀ Sinceꢀ receiverꢀ inputꢀ isꢀ usuallyꢀ
fromꢀaꢀtransmissionꢀlineꢀwhereꢀlongꢀcableꢀ
lengthsꢀ andꢀ systemꢀ interferenceꢀ canꢀ de-
gradeꢀtheꢀsignal,ꢀtheꢀinputsꢀhaveꢀaꢀtypicalꢀ
hysteresisꢀmarginꢀofꢀ500mV.ꢀThisꢀensuresꢀ
thatꢀtheꢀreceiverꢀisꢀvirtuallyꢀimmuneꢀtoꢀnoisyꢀ
transmissionꢀlines.ꢀShouldꢀanꢀinputꢀbeꢀleftꢀ
unconnected,ꢀanꢀinternalꢀ5KΩꢀpulldownꢀre-
sistorꢀtoꢀgroundꢀwillꢀcommitꢀtheꢀoutputꢀofꢀ
theꢀreceiverꢀtoꢀaꢀHIGHꢀstate.
®
AutoꢀOn-line ꢀPlusꢀenabled,ꢀtheꢀSP3224E-
SP3227Eꢀ reduceꢀ supplyꢀ currentꢀ toꢀ 1µAꢀ
wheneverꢀtheꢀtransceiversꢀareꢀinꢀidle.ꢀꢀInꢀ
shutdown,ꢀtheꢀinternalꢀchargeꢀpumpꢀandꢀ
theꢀdriversꢀwillꢀshutꢀdown.ꢀThisꢀfeatureꢀal-
lowsꢀdesignꢀengineersꢀtoꢀaddressꢀpowerꢀ
savingꢀ concernsꢀ withoutꢀ majorꢀ designꢀ
changes.
Theorꢀ Of Operation
TheꢀSP3224E-SP3227Eꢀareꢀmadeꢀupꢀofꢀ
fourꢀbasicꢀcircuitꢀblocks:ꢀ1.ꢀDrivers,ꢀ2.ꢀRe-
ceivers,ꢀ ꢀ 3.ꢀ theꢀ Exarꢀ proprietaryꢀ chargeꢀ
®
pump,ꢀandꢀ4.ꢀAutoꢀOn-line ꢀPlusꢀcircuitry.
Charge Pump
TheꢀchargeꢀpumpꢀisꢀaꢀExar–patentedꢀde-
signꢀ (USꢀ Patentꢀ #5,306,954)ꢀ andꢀ usesꢀ aꢀ
uniqueꢀapproachꢀcomparedꢀtoꢀolderꢀless-
efficientꢀ designs.ꢀ Theꢀ chargeꢀ pumpꢀ stillꢀ
requiresꢀfourꢀexternalꢀcapacitors,ꢀbutꢀusesꢀ
aꢀfourꢀphaseꢀvoltageꢀshiftingꢀtechniqueꢀtoꢀ
attainꢀ symmetricalꢀ 5.5Vꢀ powerꢀ supplies.ꢀ
Theꢀ internalꢀ powerꢀ supplyꢀ consistsꢀ ofꢀ aꢀ
regulatedꢀdualꢀchargeꢀpumpꢀthatꢀprovidesꢀ
outputꢀvoltagesꢀ5.5Vꢀregardlessꢀofꢀtheꢀin-
putꢀvoltageꢀ(Vcc)ꢀoverꢀtheꢀ+3.0Vꢀtoꢀ+5.5Vꢀ
range.ꢀThisꢀisꢀimportantꢀtoꢀmaintainꢀcom-
pliantꢀ RS-232ꢀ levelsꢀ regardlessꢀ ofꢀ powerꢀ
supplyꢀfluctuations.
Drivers
Theꢀ driversꢀ areꢀ invertingꢀ levelꢀ transmit-
tersꢀthatꢀconvertꢀTTLꢀorꢀCMOSꢀlogicꢀlev-
elsꢀ toꢀ 5.0Vꢀ EIA/TIA-232ꢀ levelsꢀ withꢀ anꢀ
invertedꢀsenseꢀrelativeꢀtoꢀtheꢀinputꢀlogicꢀ
levels.ꢀTypically,ꢀ theꢀ RS-232ꢀ outputꢀ volt-
ageꢀswingꢀisꢀ+5.4Vꢀwithꢀnoꢀloadꢀandꢀ+5Vꢀ
minimumꢀfullyꢀloaded.ꢀTheꢀdriverꢀoutputsꢀ
areꢀprotectedꢀagainstꢀinfiniteꢀshort-circuitsꢀ
toꢀgroundꢀwithoutꢀdegradationꢀinꢀreliabili-
ty.ꢀTheseꢀdriversꢀcomplyꢀwithꢀtheꢀEIA-TIA-
232-FꢀandꢀallꢀpreviousꢀRS-232ꢀversions.ꢀ
Unusedꢀdriverꢀinputsꢀshouldꢀbeꢀconnectedꢀ
toꢀGNDꢀorꢀVCC.
Theꢀchargeꢀpumpꢀoperatesꢀinꢀaꢀdiscontinu-
ousꢀmodeꢀusingꢀanꢀinternalꢀoscillator.ꢀIfꢀtheꢀ
outputꢀvoltagesꢀareꢀlessꢀthanꢀaꢀmagnitudeꢀ
Theꢀ driversꢀ canꢀ guaranteeꢀ outputꢀ dataꢀ
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀꢀ
THEORy OF OPERATION
isꢀ identicalꢀ toꢀ theꢀ firstꢀ phase.ꢀ Theꢀ posi-
tiveꢀterminalsꢀofꢀcapacitorsꢀC1ꢀandꢀC2ꢀareꢀ
chargedꢀfromꢀVccꢀwithꢀtheirꢀnegativeꢀtermi-
nalsꢀ initiallyꢀ connectedꢀ toꢀ ground.ꢀ C1+ꢀ isꢀ
thenꢀconnectedꢀtoꢀgroundꢀandꢀtheꢀstoredꢀ
chargeꢀ fromꢀ C1–ꢀ isꢀ superimposedꢀ ontoꢀ
C2–.ꢀ Sinceꢀ C2+ꢀ isꢀ stillꢀ connectedꢀ toꢀ Vcc
theꢀvoltageꢀpotentialꢀacrossꢀcapacitorꢀC2ꢀisꢀ
nowꢀ2ꢀxꢀVcc.
ofꢀ5.5V,ꢀtheꢀchargeꢀpumpꢀisꢀenabled.ꢀIfꢀtheꢀ
outputꢀ voltagesꢀ exceedꢀ aꢀ magnitudeꢀ ofꢀ
5.5V,ꢀtheꢀchargeꢀpumpꢀisꢀdisabled.ꢀThisꢀos-
cillatorꢀcontrolsꢀtheꢀfourꢀphasesꢀofꢀtheꢀvolt-
ageꢀ shifting.ꢀAꢀ descriptionꢀ ofꢀ eachꢀ phaseꢀ
follows.
Highly Efficient Charge Pump
Theꢀchargeꢀpumpꢀisꢀusedꢀtoꢀgenerateꢀposi-
tiveꢀ andꢀ negativeꢀ signalꢀ voltagesꢀ forꢀ theꢀ
RS-232ꢀdrivers.ꢀThisꢀenablesꢀfullyꢀcompli-
antꢀRS-232ꢀandꢀV.28ꢀsignalsꢀfromꢀaꢀsingleꢀ
3.0ꢀorꢀ5.5Vꢀpowerꢀsupply.
Phase 4
Vddꢀ transfer:ꢀ Theꢀ fourthꢀ phaseꢀ connectsꢀ
theꢀnegativeꢀterminalꢀofꢀC2ꢀtoꢀgroundꢀandꢀ
theꢀpositiveꢀterminalꢀofꢀC2ꢀtoꢀtheꢀVddꢀstor-
ageꢀ capacitor.ꢀThisꢀ transfersꢀ theꢀ doubledꢀ
(V+)ꢀvoltageꢀontoꢀC3.ꢀMeanwhile,ꢀcapaci-
torꢀC1ꢀchargedꢀfromꢀVccꢀtoꢀprepareꢀitꢀforꢀ
itsꢀnextꢀphase.ꢀꢀ
Theꢀchargeꢀpumpsꢀuseꢀfourꢀexternalꢀcapac-
itorsꢀtoꢀholdꢀandꢀtransferꢀelectricalꢀcharge.ꢀ
Theꢀ Exarꢀ patentedꢀ designꢀ (USꢀ Patentꢀ
#5,306,954)ꢀusesꢀaꢀuniqueꢀapproachꢀcom-
paredꢀ toꢀ olderꢀ lessꢀ efficientꢀ designs.ꢀTheꢀ
pumpsꢀ useꢀ aꢀ four–phaseꢀ voltageꢀ shiftingꢀ
techniqueꢀtoꢀattainꢀsymmetricalꢀV+ꢀandꢀV-ꢀ
powerꢀsupplies.ꢀAnꢀintelligentꢀcontrolꢀoscil-
latorꢀregulatesꢀtheꢀoperationꢀofꢀtheꢀchargeꢀ
pumpꢀ toꢀ maintainꢀ theꢀ properꢀ voltagesꢀ atꢀ
maximumꢀefficiency.ꢀꢀ
TheꢀExarꢀchargeꢀpumpꢀgeneratesꢀV+ꢀandꢀ
V–ꢀindependentlyꢀfromꢀVcc.ꢀHenceꢀinꢀaꢀno-
loadꢀconditionꢀV+ꢀandꢀV-ꢀwillꢀbeꢀsymmetri-
cal.ꢀOlderꢀchargeꢀpumpꢀapproachesꢀgen-
erateꢀV+ꢀandꢀthenꢀuseꢀpartꢀofꢀthatꢀstoredꢀ
chargeꢀtoꢀgenerateꢀV-.ꢀꢀBecauseꢀofꢀinherentꢀ
lossesꢀtheꢀmagnitudeꢀofꢀV-ꢀwillꢀbeꢀsmallerꢀ
thanꢀV+ꢀonꢀtheseꢀolderꢀdesigns.
Phase 1
Vssꢀ chargeꢀ storeꢀ andꢀ double:ꢀ Theꢀ posi-
tiveꢀterminalsꢀofꢀcapacitorsꢀC1ꢀandꢀC2ꢀareꢀ
chargedꢀfromꢀVccꢀwithꢀtheirꢀnegativeꢀtermi-
nalsꢀ initiallyꢀ connectedꢀ toꢀ ground.ꢀ C1+ꢀ isꢀ
thenꢀconnectedꢀtoꢀgroundꢀandꢀtheꢀstoredꢀ
chargeꢀ fromꢀ C1–ꢀ isꢀ superimposedꢀ ontoꢀ
C2–ꢀ.ꢀSinceꢀC2+ꢀisꢀstillꢀconnectedꢀtoꢀVcc
theꢀvoltageꢀpotentialꢀacrossꢀcapacitorꢀC2ꢀisꢀ
nowꢀ2ꢀxꢀVcc.
Underꢀlightlyꢀloadedꢀconditionsꢀtheꢀintelli-
gentꢀpumpꢀoscillatorꢀmaximizesꢀefficiencyꢀ
byꢀrunningꢀonlyꢀasꢀneededꢀtoꢀmaintainꢀV+ꢀ
andꢀV–.ꢀSinceꢀinterfaceꢀtransceiversꢀoftenꢀ
spendꢀmuchꢀofꢀtheirꢀtimeꢀatꢀidleꢀthisꢀpower-
efficientꢀinnovationꢀcanꢀgreatlyꢀreduceꢀtotalꢀ
powerꢀ consumption.ꢀ Thisꢀ improvementꢀ isꢀ
madeꢀpossibleꢀbyꢀtheꢀindependentꢀphaseꢀ
sequenceꢀofꢀtheꢀExarꢀchargeꢀpumpꢀ
design.
Phase 2
Vssꢀ transferꢀ andꢀ invert:ꢀ Phaseꢀ twoꢀ con-
nectsꢀtheꢀnegativeꢀterminalꢀofꢀC2ꢀtoꢀtheꢀVss
storageꢀcapacitorꢀandꢀtheꢀpositiveꢀterminalꢀ
ofꢀC2ꢀtoꢀground.ꢀThisꢀtransfersꢀtheꢀdoubledꢀ
andꢀinvertedꢀ(V–)ꢀvoltageꢀontoꢀC4.ꢀMean-
while,ꢀ capacitorꢀ C1ꢀ chargedꢀ fromꢀ Vcc to
prepareꢀitꢀforꢀitsꢀnextꢀphase.
Theꢀ clockꢀ rateꢀ forꢀ theꢀ chargeꢀ pumpꢀ typi-
callyꢀoperatesꢀatꢀgreaterꢀthanꢀ70kHzꢀallow-
ingꢀ theꢀ pumpꢀ toꢀ runꢀ efficientlyꢀ withꢀ smallꢀ
0.1μFꢀ capacitors.ꢀ Efficientꢀ operationꢀ de-
pendsꢀonꢀrapidlyꢀchargingꢀandꢀdischargingꢀ
C1ꢀandꢀC2,ꢀthereforeꢀcapacitorsꢀshouldꢀbeꢀ
mountedꢀcloseꢀtoꢀtheꢀICꢀandꢀhaveꢀlowꢀESRꢀ
(equivalentꢀseriesꢀresistance).ꢀInexpensiveꢀ
surfaceꢀmountꢀceramicꢀcapacitorsꢀ(suchꢀasꢀ
Phase 3
ꢀVddꢀchargeꢀstoreꢀandꢀdouble:ꢀPhaseꢀthreeꢀ
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ2
THEORy OF OPERATION
TheꢀSP3224E-SP3227Eꢀdevicesꢀhaveꢀtheꢀ
advancedꢀAutoꢀOn-Line ꢀPlusꢀfeatureꢀ
areꢀ widelyꢀ usedꢀ forꢀ power-supplyꢀ decou-
pling)ꢀareꢀidealꢀforꢀuseꢀonꢀtheꢀchargeꢀpump.ꢀ
Theꢀchargeꢀpumpsꢀareꢀdesignedꢀtoꢀbeꢀableꢀ
toꢀ functionꢀ properlyꢀ withꢀ aꢀ wideꢀ rangeꢀ ofꢀ
capacitorꢀstylesꢀandꢀvalues.ꢀIfꢀpolarizedꢀca-
pacitorsꢀareꢀusedꢀtheꢀpositiveꢀandꢀnegativeꢀ
terminalsꢀ shouldꢀ beꢀ connectedꢀ asꢀ shownꢀ
onꢀtheꢀTypicalꢀOperatingꢀCircuit.
®
RS-232ꢀsignalsꢀuseꢀbothꢀpositiveꢀandꢀneg-
ativeꢀvoltagesꢀofꢀgreaterꢀthanꢀ±5Vꢀmagni-
tude.ꢀꢀReceiversꢀhaveꢀnominalꢀ5kΩꢀimped-
anceꢀtoꢀground.ꢀꢀEvenꢀwhenꢀidle,ꢀdriversꢀ
willꢀmaintainꢀoutputꢀsignalꢀvoltageꢀcreatingꢀ
aꢀcontinuousꢀcurrentꢀflow.ꢀꢀInꢀlowꢀpower,ꢀ
batteryꢀoperatedꢀdevicesꢀthisꢀconstantꢀcur-
rentꢀdrainꢀcanꢀdecreaseꢀbatteryꢀlife
Capacitanceꢀ valuesꢀ mayꢀ beꢀ increasedꢀ ifꢀ
operatingꢀatꢀhigherꢀVccꢀorꢀtoꢀprovideꢀgreat-
erꢀstabilityꢀasꢀtheꢀcapacitorsꢀage.ꢀꢀꢀ
significantly.ꢀꢀ
+
VCC
-
Phase 2 – Vss transfer from C2 to C4.
Meanwhile C1 is charged to Vcc
+
C3
+
+
+
VCC
-
V+
C1
C2
-
e
-
e
Phases 1 and 3: Store/Double.
-
e
+
Double charge from C1 onto C2.
C2 is now charged to -2xVcc
C4
Vss
+
C3
+
+
V+
V-
Patented 5,306,954
C1
C2
-
e
+
VCC
-
-
e
+
C4
Phase 4 VDD
Meanwhile C1 is charged to Vcc
transfer from C2 to C3.
VDD
+
e
+
e
+
C3
+
+
V+
C2
C1
-
e
V-
+
C4
ChargeꢀPumpꢀPhases
Minimum Recommended Charge Pump Capacitor Values
InputꢀVoltageꢀVcc
ChargeꢀPumpꢀCapacitorꢀValueꢀforꢀSP32XX
3.0Vꢀtoꢀ3.6V
Cꢀ-C4=0.ꢀµF
4.5Vꢀtoꢀ5.5V
3.0Vꢀtoꢀ5.5V
Cꢀ=0.047µF, C2-C4=0.33µF
Cꢀ-C4=0.22µF
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀChargeꢀPumpꢀCapacitorꢀValues
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SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ3
THEORy OF OPERATION
thatꢀsavesꢀpowerꢀbyꢀturningꢀoffꢀtheꢀchargeꢀ
pumpsꢀandꢀdriverꢀoutputsꢀwhenꢀtheꢀtrans-
ceiverꢀinputsꢀareꢀidleꢀforꢀmoreꢀthanꢀ30ꢀsec-
logicꢀLOWꢀforcesꢀtheꢀdeviceꢀintoꢀshutdownꢀ
stateꢀregardlessꢀofꢀinputꢀactivityꢀorꢀtheꢀsta-
tusꢀofꢀtheꢀONLINE pin.
®
onds.ꢀAutoꢀ On-line ꢀ Plusꢀ isꢀ equivalentꢀ toꢀ
Maxim’sꢀ“AutoꢀShutdownꢀPlus”ꢀfeature.ꢀꢀItꢀ
differsꢀfromꢀourꢀexistingꢀAutoꢀOn-line ꢀbyꢀ
TheꢀSTATUSꢀoutputꢀdeterminesꢀwhetherꢀaꢀ
validꢀRS-232ꢀsignalꢀvoltageꢀisꢀpresentꢀonꢀ
theꢀinputs.ꢀꢀTheꢀSTATUSꢀpinꢀgoesꢀtoꢀaꢀlogicꢀ
LOWꢀwhenꢀtheꢀreceiverꢀinputꢀsignalꢀlevelsꢀ
collapseꢀnearꢀreferenceꢀground.ꢀThisꢀmayꢀ
occurꢀ whenꢀ theꢀ RS-232ꢀ cableꢀ isꢀ discon-
nectedꢀ orꢀ theꢀ RS-232ꢀ driversꢀ ofꢀ theꢀ con-
nectedꢀperipheralꢀareꢀturnedꢀoff.ꢀꢀ
®
relyingꢀ onꢀ signalꢀ transitionsꢀ ratherꢀ thanꢀ
voltageꢀ levelsꢀ toꢀ triggerꢀ shutdownꢀ andꢀ
wakeup.ꢀꢀ
®
AutoꢀOn-Line ꢀPlusꢀꢀautomaticallyꢀputsꢀtheꢀ
deviceꢀintoꢀaꢀstandbyꢀmodeꢀwhereꢀitꢀdrawsꢀ
onlyꢀ1μAꢀtypical.ꢀꢀWhenꢀtheꢀdeviceꢀdetectsꢀ
activityꢀonꢀeitherꢀtheꢀreceiverꢀorꢀdriverꢀin-
putsꢀitꢀwillꢀautomaticallyꢀawakeꢀandꢀactivateꢀ
toꢀ allowꢀ serialꢀ communication.ꢀ ꢀ Bothꢀ theꢀ
wakeupꢀ andꢀ shutdownꢀ happenꢀ automati-
STATUSꢀmayꢀbeꢀusedꢀtoꢀindicateꢀDTRꢀorꢀaꢀ
RingꢀIndicatorꢀsignalꢀorꢀtoꢀdetermineꢀwheth-
erꢀaꢀliveꢀRS232ꢀdriverꢀorꢀcableꢀisꢀconnect-
ed.ꢀ Byꢀ connectingꢀ theꢀ STATUSꢀ outputꢀ toꢀ
ONLINEꢀinput,ꢀtheꢀSP3224E-SP3227Eꢀwillꢀ
shutꢀdownꢀwhenꢀnoꢀvalidꢀsignalꢀlevelꢀandꢀ
noꢀinputꢀtransitionsꢀareꢀdetected,ꢀandꢀwakeꢀ
upꢀonꢀaꢀvalidꢀsignalꢀlevelꢀorꢀsignalꢀedge.ꢀꢀIfꢀitꢀ
detectsꢀnoꢀsignalꢀtransitionsꢀwithꢀtheꢀpastꢀ30ꢀ
Receiver
5kΩ
EDGE
+0.3V
T_IN
DETECT
SHUTDOWN
S
AUTO ONLINE
R_IN
-0.3V
30s
30µs
timer
EDGE
STATUS
timer
A
R_IN
DETECT
INVALID ASSERTED IF ALL RECEIVER INPUTS ARE
BETWEEN +0.3V AND -0.3V FOR AT LEAST 30µS
ONLINE
Figure 3c. Auto On-line¨ Plus Logic
Figure 3a.STATUS Functional Diagram STATUS low
+2.7V
R_IN
SHUTDOWN
POWERDOWN
ONLINE
AUTO ONLINE
30µs
STATUS
timer
-2.7V
POWERDOWN IS ONLY A INTERNAL SIGNAL. IT
CONTROLS THE OPERATIONAL STATUS TO THE
TRANSMITTERS AND THE POWER SUPPLIES.
INVALID DEASSERTED IF ALL RECEIVER INPUTS ARE
BETWEEN +2.7V AND -2.7V FOR AT LEAST 30µS
Figure 3d. Powerdown Logic
Figure 3b. STATUS Functional Diagram, STATUS high.
cally,ꢀwithoutꢀanyꢀuserꢀintervention,ꢀspecialꢀ
drivers,ꢀorꢀsoftwareꢀmodifications.ꢀ
seconds,ꢀtheꢀdeviceꢀwillꢀgoꢀintoꢀlowꢀpowerꢀ
mode.ꢀByꢀconnectingꢀtheꢀSTATUSꢀoutputꢀtoꢀ
bothꢀꢀtheꢀONLINEꢀinputꢀandꢀSHUTDOWN
inputꢀpins,ꢀtheꢀdeviceꢀentersꢀintoꢀshutdownꢀ
whenꢀnotꢀreceivingꢀaꢀvalidꢀRS-232ꢀsignalꢀvoltageꢀ
input.
Wakeupꢀ andꢀ shutdownꢀ canꢀ beꢀ exter-
nallyꢀ controlledꢀ byꢀ theꢀ ONLINE and
SHUTDOWNꢀpins.ꢀꢀWhenꢀONLINEꢀisꢀdriv-
®
enꢀ toꢀ logicꢀ LOW,ꢀ theꢀAutoꢀ On-line ꢀ Plus
functionꢀisꢀactive.ꢀꢀDrivingꢀSHUTDOWN to
WhenꢀtheꢀSP3224E-SP3227Eꢀdevicesꢀareꢀ
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SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ4
THEORy OF OPERATION
shutꢀdown,ꢀtheꢀchargeꢀpumpsꢀareꢀturnedꢀoff.ꢀ
V+ꢀchargeꢀpumpꢀoutputꢀdecaysꢀtoꢀVCC,theꢀ
V-ꢀoutputꢀdecaysꢀtoꢀGND.ꢀTheꢀdecayꢀtimeꢀ
willꢀdependꢀonꢀtheꢀsizeꢀofꢀcapacitorsꢀusedꢀ
forꢀtheꢀchargeꢀpump.ꢀOnceꢀinꢀshutdown,ꢀtheꢀ
timeꢀrequiredꢀtoꢀexitꢀtheꢀshutdownꢀstateꢀandꢀ
haveꢀvalidꢀV+ꢀandꢀV-ꢀlevelsꢀisꢀtypicallyꢀ50μs.ꢀ
WhenꢀtheꢀSP3224E-SP3227Eꢀdriversꢀandꢀ
internalꢀchargeꢀpumpꢀareꢀdisabled,ꢀtheꢀsup-
plyꢀcurrentꢀisꢀreducedꢀtoꢀ1μA.
AutoꢀOn-Lineꢀ(existing)
Deviceꢀentersꢀlow-powerꢀmodeꢀifꢀreceiverꢀinputsꢀseeꢀlessꢀthanꢀvalidꢀ+/-ꢀ3V.
STATUSꢀ(orꢀINVALID)ꢀsignalꢀoutputꢀindicatesꢀifꢀvalidꢀsignalꢀvoltageꢀisꢀatꢀ
receivers.
AutoꢀOn-LineꢀPlusꢀ(new) Deviceꢀentersꢀlow-powerꢀmodeꢀifꢀdriverꢀinputsꢀorꢀreceiverꢀinputsꢀseeꢀnoꢀ
transitionsꢀforꢀ30ꢀseconds.ꢀꢀReturnꢀtoꢀfullꢀpowerꢀmodeꢀuponꢀanyꢀtransitionꢀonꢀ
anyꢀdriverꢀinputꢀorꢀreceiverꢀinput
Shutdownꢀoccursꢀevenꢀifꢀdataꢀcableꢀisꢀconnectedꢀtoꢀanꢀactiveꢀdriver,ꢀasꢀlongꢀ
asꢀallꢀinputsꢀremainꢀunchanged
STATUSꢀ(orꢀINVALID)ꢀsignalꢀfunctionsꢀasꢀbefore.ꢀꢀIndicatesꢀifꢀvalidꢀsignalꢀ
voltageꢀisꢀpresent.ꢀꢀButꢀhasꢀnoꢀeffectꢀonꢀshutdown
ForꢀSP3224EꢀtheꢀENꢀinputꢀisꢀreplacedꢀwithꢀaꢀREADYꢀoutput.ꢀꢀREADYꢀdrivesꢀ
highꢀwhenꢀchargeꢀpumpꢀachievesꢀgreaterꢀthanꢀ-4VꢀVssꢀ(V-).ꢀꢀIndicatesꢀ“readyꢀ
toꢀtransmit.”
®
ComparisonꢀofꢀAutoꢀOn-line Features
OperatingꢀMode
ONLINE
SHDN
|Rin| >
±2.7V
IdleꢀInputsꢀ
(Rxin &
Txin)
Txout
Rxout
ForcedꢀShutdown
ForcedꢀOn-Line
X
0
ꢀ
X
X
X
X
Hi-Z
Active
Active
ꢀ
Active
AutoꢀOn-LineꢀPlus
(Wakeꢀwhenꢀactive)
0
ꢀ
X
Active
Active
Hi-Z
Active
Active
Active
Active
Active
Active
Active
AutoꢀOnꢀLineꢀPlus
(Off-Lineꢀwhenꢀidle)
0
ꢀ
X
Idleꢀ>ꢀ30s
AutoꢀOn-LineꢀPlus
(Wakeꢀonꢀcable)
STATUS
STATUS
STATUS
STATUS
STATUS
ꢀ
Yes
No
No
Yes
No
X
Active
Active
Hi-Z
AutoꢀOn-LineꢀPlus
(Wakeꢀwhenꢀactive)
ꢀ
Active
AutoꢀOn-LineꢀPlus
(Off-Lineꢀwhenꢀidle)
ꢀ
Idleꢀ>ꢀ30s
AutoꢀOn-Line
(Wakeꢀonꢀcable)
STATUS
STATUS
X
X
Active
Hi-Z
AutoꢀOn-Line
(AutoꢀShutoff)
®
AutoꢀOn-line ꢀPlusꢀTruthꢀTable
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ5
THEORy OF OPERATION
RECEIVER
INPUTS
INVALID
REGION
}
TRANSMITTER
INPUTS
TRANSMITTER
OUTPUTS
Vcc
0
STATUS
OUTPUT
t
TSTL
t
STH
t
t
OFFLINE
OFFLINE
t
ONLINE
t
ONLINE
Vcc
0
OUTPUT
V+
Vcc
0
V-
ꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀꢀAutoꢀOn-Line® ꢀPlusꢀTimingꢀDiagram
tstl (=30µsꢀtyp.)
tsth (=0.4µsꢀtyp.)
toffline (=30sꢀtyp.)
tonline (=100µsꢀtyp.)
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SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ6
TyPICAL OPERATING CIRCUIT
VCC
+
+
15
CC
0.1µ F
0.1µ F
C5
C1
V
3
2
C1+
V+
+
0.1µ F
0.1µ F
C3
C4
4
5
C1-
SP3224E
SP3225E
7
C2+
V-
+
C2
0.1µ F
+
6
C2-
T1OUT
T2OUT
17
8
13 T1IN
12 T2IN
LOGIC
RS-232
OUTPUTS
INPUTS
15
10
R1IN 16
R1OUT
R2OUT
5kΩ
RS-232
INPUTS
LOGIC
OUTPUTS
9
R2IN
5kΩ
1
11
20
READY
ONLINE
STATUS
14
VCC
SHUTDOWN
GND
18
VCC
+
15
CC
0.1µ F
0.1µ F
C5
C1
V
3
7
2
C1+
V+
+
+
+
0.1µ F
0.1µ F
C3
4
5
C1-
SP3226E
SP3227E
C2+
V-
C4
C2
0.1µ F
+
6
C2-
LOGIC
INPUT
RS-232
T1OUT
R1IN
13
8
11 T1IN
OUTPUT
9
RS-232
INPUT
R1OUT
LOGIC
OUTPUT
5kΩ
1
10
16
READY
ONLINE
STATUS
12
VCC
SHUTDOWN
GND
14
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SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ7
PINOUT DIAGRAMS
SHUTDOWN
VCC
READY
C1+
20
19
18
1
2
GND
T1OUT
V+ 3
C1-
17
4
SP3224E
SP3225E
R1IN
16
15
14
13
12
11
C2+ 5
C2- 6
V-
R1OUT
ONLINE
7
8
T1IN
T2OUT
T2IN
R2IN 9
R2OUT
STATUS
10
SHUTDOWN
VCC
READY
C1+
16
15
14
1
2
GND
V+ 3
C1-
T1OUT
13
4
SP3226E
SP3227E
C2+ 5
C2- 6
V-
12 ONLINE
T1IN
11
10
9
STATUS
R1OUT
7
8
R1IN
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SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ8
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
ꢀ9
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
20
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
2ꢀ
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
22
ORDERING INFORMATION
Part number
SP3224ECA-L
SP3224ECY-L
SP3224EEA-L
SP3224EEY-L
SP3225ECA-L
SP3225ECY-L
SP3225EEA-L
SP3225EEY-L
SP3226ECA-L
SP3226ECY-L
SP3226EEA-L
SP3226EEY-L
SP3227ECA-L
SP3227ECY-L
SP3227EEA-L
SP3227EEY-L
AvailableꢀinꢀTapeꢀonꢀReel
Temperature range
From 0°Cꢀtoꢀ+70°C
From 0°Cꢀtoꢀ+70°C
From -40°Cꢀtoꢀ+85°C
From -40°Cꢀtoꢀ+85°C
From 0°Cꢀtoꢀ+70°C
From 0°Cꢀtoꢀ+70°C
From -40°Cꢀtoꢀ+85°C
From -40°Cꢀtoꢀ+85°C
From 0°Cꢀtoꢀ+70°C
From 0°Cꢀtoꢀ+70°C
From -40°Cꢀtoꢀ+85°C
From -40°Cꢀtoꢀ+85°C
From 0°Cꢀtoꢀ+70°C
From 0°Cꢀtoꢀ+70°C
From -40°Cꢀtoꢀ+85°C
From -40°Cꢀtoꢀ+85°C
Package Tꢀpe
LeadꢀFreeꢀ20ꢀpinꢀSSOP
LeadꢀFreeꢀ20ꢀpinꢀTSSOP
LeadꢀFreeꢀ20ꢀpinꢀSSOP
LeadꢀFreeꢀ20ꢀpinꢀTSSOP
LeadꢀFreeꢀ20ꢀpinꢀSSOP
LeadꢀFreeꢀ20ꢀpinꢀTSSOP
LeadꢀFreeꢀ20ꢀpinꢀSSOP
LeadꢀFreeꢀ20ꢀpinꢀTSSOP
LeadꢀFreeꢀ16ꢀpinꢀSSOP
LeadꢀFreeꢀ16ꢀPINꢀSSOP
LeadꢀFreeꢀ16ꢀpinꢀSSOP
LeadꢀFreeꢀ16ꢀPINꢀTSSOP
LeadꢀFreeꢀ16ꢀPINꢀSSOP
LeadꢀFreeꢀ16ꢀPINꢀTSSOP
LeadꢀFreeꢀ16ꢀPINꢀSSOP
LeadꢀFreeꢀ16ꢀPINꢀTSSOP
DATE
REVISION DESCRIPTION
ꢀꢀ-20-06
ꢀ2-ꢀ4-09
P
LegacyꢀSipexꢀDatasheet
ꢀ.0.0
UpdateꢀtoꢀExarꢀFormat.ꢀChangeꢀrevisionꢀtoꢀ1.0.0.ꢀChangeꢀSupplyꢀCurrentꢀActiveꢀ
overꢀfullꢀVccꢀrangeꢀmaximumꢀfromꢀ2.0mAꢀtoꢀ3.0mA.ꢀChangeꢀSupplyꢀCurrentꢀActiveꢀ
atꢀVccꢀ=ꢀ3.3Vꢀmaximumꢀfromꢀ1.0mAꢀtoꢀ2.0mA.ꢀChangeꢀRXꢀinputꢀvoltageꢀABSꢀMaxi-
mumꢀRatingꢀfromꢀ+/-18Vꢀtoꢀ+/-16V.
08-ꢀ7-ꢀꢀ
ꢀ.0.ꢀ
CorrectꢀtypeꢀerrorꢀonꢀfrontꢀpageꢀFeaturesꢀlist.
Notice
EXARꢀCorporationꢀreservesꢀtheꢀrightꢀtoꢀmakeꢀchangesꢀtoꢀanyꢀproductsꢀcontainedꢀinꢀthisꢀpublicationꢀinꢀorderꢀtoꢀimproveꢀdesign,ꢀperformanceꢀorꢀreliabil-
ity.ꢀꢀEXARꢀCorporationꢀassumesꢀnoꢀrepresentationꢀthatꢀtheꢀcircuitsꢀareꢀfreeꢀofꢀpatentꢀinfringement.ꢀChartsꢀandꢀschedulesꢀcontainedꢀhereinꢀareꢀonlyꢀforꢀ
illustrationꢀpurposesꢀandꢀmayꢀvaryꢀdependingꢀuponꢀaꢀuser'sꢀspecificꢀapplication.ꢀWhileꢀtheꢀinformationꢀinꢀthisꢀpublicationꢀhasꢀbeenꢀcarefullyꢀchecked;
noꢀresponsibility,ꢀhowever,ꢀisꢀassumedꢀforꢀinaccuracies.
EXARꢀCorporationꢀdoesꢀnotꢀrecommendꢀtheꢀuseꢀofꢀanyꢀofꢀitsꢀproductsꢀinꢀlifeꢀsupportꢀapplicationsꢀwhereꢀtheꢀfailureꢀorꢀmalfunctionꢀofꢀtheꢀproductꢀcanꢀ
reasonablyꢀbeꢀexpectedꢀtoꢀcauseꢀfailureꢀofꢀtheꢀlifeꢀsupportꢀsystemꢀorꢀtoꢀsignificantlyꢀaffectꢀitsꢀsafetyꢀorꢀeffectiveness.ꢀProductsꢀareꢀnotꢀauthorizedꢀforꢀ
useꢀinꢀsuchꢀapplicationsꢀunlessꢀEXARꢀCorporationꢀreceives,ꢀinꢀwritting,ꢀassurancesꢀtoꢀitsꢀsatisfactionꢀthat:ꢀ(a)ꢀtheꢀriskꢀofꢀinjuryꢀorꢀdamageꢀhasꢀbeenꢀ
minimizedꢀ;ꢀ(b)ꢀtheꢀuserꢀassumesꢀallꢀsuchꢀrisks;ꢀ(c)ꢀpotentialꢀliabilityꢀofꢀEXARꢀCorporationꢀisꢀadequatelyꢀprotectedꢀunderꢀtheꢀcircumstances.
Copyrightꢀ2011ꢀEXARꢀCorporation
DatasheetꢀAugustꢀ2011
Sendꢀyourꢀserialꢀtransceiverꢀtechnicalꢀinquiryꢀwithꢀtechnicalꢀdetailsꢀto:ꢀꢀserialtechsupport@exar.com
Reproduction,ꢀinꢀpartꢀorꢀwhole,ꢀwithoutꢀtheꢀpriorꢀwrittenꢀconsentꢀofꢀEXARꢀCorporationꢀisꢀprohibited.
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 5ꢀ0-668-70ꢀ7 • www.exar.com
SP3224E,3225E,3226E,3227E_ꢀ0ꢀ_08ꢀ7ꢀꢀ
23
相关型号：
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