TC9400/9401/9402 - Microchip Technology

1 2007 Microchip Technology 1TC9400/9401/9402 Features:VOLTAGE-TO-FREQUENCY Choice of Linearity:- TC9401: - tc9400 : - TC9402: DC to 100 kHz (F/V) or 1 Hz to 100 kHz (V/F) Low Power Dissipation: 27 mW (Typ.) Single/Dual Supply Operation:- +8V to +15V or 4V to Gain Temperature Stability: 25 ppm/ C (Typ.) Programmable Scale FactorFREQUENCY-TO-VOLTAGE Operation: DC to 100 kHz Choice of Linearity:- TC9401: tc9400 : TC9402: Programmable Scale FactorApplications: Microprocessor Data Acquisition 13-bit Analog-to-Digital Converters (ADC) Analog Data Transmission and Recording Phase Locked Loops Frequency Meters/Tachometer Motor Control FM DemodulationGeneral Description:The TC9400/9401/9402 are low-cost Voltage-to-Fre-quency (V/F) converters, utilizing low-power CMOS Technology .

2 The converters accept a variable analoginput signal and generate an output pulse train, whosefrequency is linearly proportional to the input devices can also be used as highly accurateFrequency-to-Voltage (F/V) converters, acceptingvirtually any input frequency waveform and providing alinearly proportional voltage complete V/F or F/V system only requires theaddition of two capacitors, three resistors, and refer-ence Type1234567141312111098 VDDNCAMPLIFIER OUTTHRESHOLDDETECTORFREQ/2 OUTOUTPUT COMMONPULSE FREQ OUTIBIASZERO ADJIINVSSVREFOUTGNDVREF12345671413121110 98TC9400TC9401TC940214-Pin Plastic DIP/CERDIP14-Pin SOICTC9400TC9401TC9402NC = No Internal ConnectionVDDNCAMPLIFIER OUTTHRESHOLDDETECTORFREQ/2 OUTOUTPUT COMMONPULSE FREQ OUTIBIASZERO ADJIINVSSVREFOUTGNDVREFV oltage-to-Frequency / Frequency-to-Voltage ConvertersTC9400/9401/9402DS21483D-page 2 2007 Microchip Technology Block DiagramIINIREFTC9400 RINI ntegratorOp AmpIntegratorCapacitorThresholdDetectorO ne ShotPulse OutputPulse/2 Output 2 InputVoltageReferenceCapacitorReferenceV oltage 2007 Microchip Technology 3TC9400/9401 CHARACTERISTICSA bsolute Maximum Ratings VDD VSS.

3 + mAVOUTMAX VOUT VSS .. Temperature Range ..-65 C to +150 COperating Temperature Range: C Device .. 0 C to +70 C E C to +85 CPackage Dissipation (TA 70 C): 8-Pin CerDIP ..800 mW 8-Pin Plastic DIP ..730 mW 8-Pin SOIC ..470 mW Stresses above those listed under Absolute MaximumRatings may cause permanent damage to the device. Theseare stress ratings only and functional operation of the deviceat these or any other conditions above those indicated in theoperation sections of the specifications is not to Absolute Maximum Rating conditions forextended periods may affect device ELECTRICAL SPECIFICATIONSE lectrical Characteristics: unless otherwise specified, VDD = +5V, VSS = -5V, VGND = 0V, VREF = -5V, RBIAS = 100 k , Full Scale = 10 kHz.

4 TA = +25 C, unless temperature range is specified (-40 C to +85 C for E device, 0 C to +70 C for C device).ParameterMinTypMaxMinTypMaxMinTy pMaxUnitsTest ConditionsVoltage-to-FrequencyAccuracyTC 9400TC9401TC9402 Linearity 10 kHz Full ScaleOutput Deviation from Straight Line Between Normalized Zero and Full Scale InputLinearity 100 kHz Full ScaleOutput Deviation from Straight Line Between Normalized Zero Read-ing and Full Scale InputGain TemperatureDrift (Note 1) 25 40 25 40 50 100 ppm/ CFull ScaleVariation in Gain A due to Temperature ChangeGain Variance 10 10 10 % ofNominalVariation from Ideal AccuracyZero Offset (Note 2) 10 50 10 50 20 100mVCorrection at Zero Adjust for Zero Output when Input is ZeroZero TemperatureDrift (Note 1) 25 50 25 50 50 100 V/ CVariation in Zero Offset Due to Temperature Change Note 1.

5 Full temperature range; not : IIN = :Full temperature range, IOUT = 10 :IOUT = 10 :Threshold Detect = 5V, Amp Out = 0V, full temperature :10 Hz to 100 kHz; not :5 s minimum positive pulse width and s minimum negative pulse :tR = tF = 20 :RL 2k , tested @ 10 k .10:Full temperature range, VIN = 4 2007 Microchip Technology InputIIN Full Scale 10 10 10 AFull Scale Analog Input Current to achieve Specified AccuracyIIN Over Range 50 50 50 AOver Range CurrentResponse Time 2 2 2 CycleSettling Time to Full ScaleDigital SectionTC9400TC9401TC9402 VSAT @ IOL = 10mA 0 Output Voltage (Note 3)VOUTMAX VOUTC ommon (Note 4) 18 18 18 VVoltage Range Between Output and CommonPulse FrequencyOutput Width 3 3 3 sFrequency-to-VoltageSupply CurrentIDD Quiescent(Note 5) 310mACurrent Required from Positive Supply during OperationISS Quiescent(Note 5)

6 -3-10mACurrent Required from Negative Supply during OperationVDD Supply4 Range of Positive SupplyVSS Supply-4 Range of Negative SupplyReference VoltageVREF VRange of Voltage Reference InputAccuracyNon-Linearity (Note 10) ScaleDeviation from ideal Transfer Function as a Percentage Full Scale VoltageInput FrequencyRange (Notes 7 and 8)10 100k10 100k10 100kHzFrequency Range for Specified Non-LinearityTC940X ELECTRICAL SPECIFICATIONS (CONTINUED)Electrical Characteristics: unless otherwise specified, VDD = +5V, VSS = -5V, VGND = 0V, VREF = -5V, RBIAS = 100 k , Full Scale = 10 kHz. TA = +25 C, unless temperature range is specified (-40 C to +85 C for E device, 0 C to +70 C for C device).ParameterMinTypMaxMinTypMaxMinTy pMaxUnitsTest ConditionsNote 1:Full temperature range; not : IIN = :Full temperature range, IOUT = 10 :IOUT = 10 :Threshold Detect = 5V, Amp Out = 0V, full temperature :10 Hz to 100 kHz; not :5 s minimum positive pulse width and s minimum negative pulse :tR = tF = 20 :RL 2k , tested @ 10 k.

7 10:Full temperature range, VIN = 2007 Microchip Technology 5TC9400/9401/9402 Frequency InputPositive VDDVV oltage Required to Turn Threshold Detector OnNegative -2 VVoltage Required to Turn Threshold Detector OffMinimum PositivePulse Width(Note 8) 5 5 5 sTime between Threshold CrossingsMinimum NegativePulse Width (Note 8) sTime Between Threshold CrossingsInput Impedance 10 10 10M Analog OutputsTC9400TC9401TC9402 Output Voltage(Note 9) VDD 1 VDD 1 VDD 1 VVoltage Range of Op Amp Output for Specified Non-LinearityOutput Loading2 2 2 k Resistive Loading at Output of Op AmpSupply CurrentTC9400TC9401TC9402 IDD Quiescent(Note 10) 310mACurrent Required from Positive Supply During OperationISS Quiescent(Note 10) -3-10mACurrent Required from Negative Supply During OperationVDD Supply4 Range of Positive SupplyVSS Supply-4 Range of Negative SupplyReference VoltageVREF VRange of Voltage Reference InputTC940X ELECTRICAL SPECIFICATIONS (CONTINUED)Electrical Characteristics: unless otherwise specified, VDD = +5V, VSS = -5V, VGND = 0V, VREF = -5V, RBIAS = 100 k , Full Scale = 10 kHz.

8 TA = +25 C, unless temperature range is specified (-40 C to +85 C for E device, 0 C to +70 C for C device).ParameterMinTypMaxMinTypMaxMinTy pMaxUnitsTest ConditionsNote 1:Full temperature range; not : IIN = :Full temperature range, IOUT = 10 :IOUT = 10 :Threshold Detect = 5V, Amp Out = 0V, full temperature :10 Hz to 100 kHz; not :5 s minimum positive pulse width and s minimum negative pulse :tR = tF = 20 :RL 2k , tested @ 10 k .10:Full temperature range, VIN = 6 2007 Microchip Technology DESCRIPTIONSThe descriptions of the pins are listed in Table 2-1:PIN FUNCTION Current (IBIAS)An external resistor, connected to VSS, sets the biaspoint for the tc9400 . Specifications for the tc9400 arebased on RBIAS = 100 k 10%, unless otherwisenoted. Increasing the maximum frequency of the TC9400beyond 100 kHz is limited by the pulse width of thepulse output (typically 3 s).

9 Reducing RBIAS willdecrease the pulse width and increase the maximumoperating frequency, but linearity errors will alsoincrease. RBIAS can be reduced to 20 k , which willtypically produce a maximum full scale frequency of500 kHz. AdjustThis pin is the non-inverting input of the operationalamplifier. The low frequency set point is determined byadjusting the voltage at this Current (IIN)The inverting input of the operational amplifier and thesumming junction when connected in the V/F mode. Aninput current of 10 A is specified, but an over rangecurrent up to 50 A can be used without detrimentaleffect to the circuit operation. IIN connects the summingjunction of an operational amplifier. Voltage sourcescannot be attached directly, but must be buffered byexternal Capacitor (VREF Out)The charging current for CREF is supplied through thispin.

10 When the op amp output reaches the thresholdlevel, this pin is internally connected to the referencevoltage and a charge, equal to VREF x CREF, is removedfrom the integrator capacitor. After about 3 sec, this pinis internally connected to the summing junction of theop amp to discharge CREF. Break-before-make switch-ing ensures that the reference voltage is not directlyapplied to the summing Reference (VREF)A reference voltage from either a precision source, orthe VSS supply is applied to this pin. Accuracy of theTC9400 is dependent on the voltage regulation andtemperature characteristics of the reference the tc9400 is a charge balancing V/F converter,the reference current will be equal to the input this reason, the DC impedance of the referencevoltage source must be kept low enough to preventlinearity errors.