HM9270C中文资料
- 格式：pdf
- 大小：69.67 KB
- 文档页数：10
DTMF RECEIVERHM 9270C/D
- 1 -General DescriptionThe HM 9270C/D is a complete DTMF receiver integrating both the bandsplit filter and digital decoderfunctions. The filter section uses switched capacitor techniques for high- and low-group filters and dial-tonerejection. Digital counting techniques are employed in the decoder to detect and decode all 16 DTMF tone-pairs into a 4-bit code. External component count is minimized by on-chip provision of a differential inputamplifier, clock-oscillator and latched 3-state bus interface.Features•Complete receiver in an 18-pin package.•Excellent performance.•CMOS, single 5 volt operation.•Minimum board area.•Central office quality.•Low power consumption.•Power-Down mode (HM9270D only).•Inhibit-mode (HM9270D only).Pin Configurations
* Connect to VSSHM9270CIN+INGSIC*IC*OSC1OSC2VDDVREFEStStDQ4Q3Q2Q1TOESt/GT
VSS123456789181716151413121110HM9270DIN+INGSINHPWDNOSC1OSC2VDDVREFEStStDQ4Q3Q2Q1TOESt/GT
VSS123456789181716151413121110元器件交易网www.cecb2b.com DTMF RECEIVERHM 9270C/D
- 2 -Block Diagram (Figure 1)
Pin Sym.1IN+2IN-3GS4VREF5INH6PWDN7OSC18OSC29VSS10TOENon-Inverting inputInvering InputGain select. Gives access to output of front-end differential amplifier for connection offeedback resistor.Reference voltage output,nominally VDD/2. May be used to bias the inputs at midrail (seeapplication diagram).Inhibit (input) logic high inhibit the detection of 1633Hz internal built-in pull down resistor.(HM9270D only).Power down (input). Active high power down the device and inhibit the oscillator internalbuilt-in pull down resistor. (HM9270D only).Clock InputClockOutputNegative power supply, normally connected to 0V.3-state data output enable (input). Logic high enables the outputs Q1-Q4. Internal pull-up.Connections to the front-end differential amplifier. FunctionPin Description
3.579545 MHz crystal connected between these pins completesinternal oscillator.Q1Q2Q3Q4
OSC1OSC2GSININ++-CHIPCLOCKSCHIPPOWERCHIPBIASCHIPREFDIALTONEFILTERHIGHGROUPFILTERLOWGROUPFILTERBIASCIRCUIT+-ZEROCROSSINGDETECTORSDIGITALDETECTIONALGORITHMCODECONVERTERANDLATCHSTEERINGLOGICTOEStDVDDVSSVREFSt/ GTEStINH
PWDN元器件交易网www.cecb2b.com DTMF RECEIVERHM 9270C/D
- 3 - Pin Sym. Function11Q112Q213Q314Q415StD16ESt17St/GT18VDD3-state data outputs. When enabled by TOE, provide the code corresponding to the last validtone-pair received (see code table).Delayed steering output. Presents a logic high when a received tone-pair has been registeredand the output latch updated; returns to logic low when the voltage on St/GT falls belowVTSt.Early steering output. Presents a logic high immediately when the digital algorithm detects arecognizable tone-pair (signal condition). Any momentary loss of signal condition will causeESt to return to a logic low.Steering input/guard time output (bi-directional). A voltage greater than VTSt detected at Stcauses the device to register the detected tone-pair and update the output latch. A voltageless than VTSt frees the device to accept a new tone-pair. The GT output acts to reset theexternal steering time-constant; its state is a function of ESt and the voltage on St (see truthtable).Positive power supply, +5Volts.
DC Electrical CharacteristicsParameter DescriptionSUPPLY:VDDOperating Supply VoltageIccOperating Supply CurrentPoPower ConsumptionISStandby CurrentINPUTS:VILLow Level Input VoltageVIHHigh Level Input VoltageIIH/IILInput Leakage CurrentIsoPull Up (Source) CurrentRINInput SignalImpedance Inputs 1,2VTStSteering Threshold Voltage Test ConditionsMin.Typ.Max.Units4.755.25V3.07mAf=3.579MHz; VDD=5V1535mWPWDN pin = VDD--100µA1.5V3.5VVIN=Vss or VDD0.1uATOE (Pin 10)=OV7.515uA@ 1kHz10 MΩ2.35
VParametersMin.Max.Units Power Supply Voltage, VDD - VSS6V Voltage on any pinVSS - 0.3VDD+ 0.3V Current at any pin10 mA Operating temperature-40+85oC Storage temperature-65+150oC Package power dissipation500 mWNote1. Absolute maximum ratings are those values beyond which damage to the device mayoccur.2. Unless otherwise specified, all voltages are referenced to ground.3. Power dissipation temperature derating: -12 mV/oC from 65oC to 85oCAbsolute Maximum Ratings (Notes 1, 2 and 3)元器件交易网www.cecb2b.com DTMF RECEIVERHM 9270C/D
- 4 - Test ConditionsMin.Typ. Max. UnitsNo Load0.03VNo Load4.97VVOUT=0.4V1.02.5 mAVOUT=4.6V0.40.8 mANo Load2.42.7V10KΩOUTPUTS: VOLLow Level Output Voltage VOHHigh Level Output Voltage IOLOutput Low (Sink) Current IOHOutput High (Source) CurrentVREFOutput Voltage VREFROROutput ResistanceOperating CharacteristicsGain Setting AmplifierIINInput Leakage CurrentVSS < VIN < VDD±100nARINInput Resistance10MΩVOSInput Offset Voltage±25mVPSRRPower Supply Rejection1kHz60dBCMRRCommon Mode Rejection-3.0V
