UTC TA31142 LINEAR INTEGRATED CIRCUIT LOW POWER IF RECEIVER IC DESCRIPTION The UTC TA31142 is a low power IF receiver IC and is suitable for use as the second IF downconverter in double-conversion paging systems. It is well-suited for POCSAG paging applications and incorporates a 2-level FSK demodulator consisting of a quadrature FM demodulator, on-chip bit-rate filter, and 1-bit comparator. An on-chip 1V regulator is provided for convenient biasing of off-chip circuitry. FEATURES TSSOP-20 *Extremely low power operation with power-down feature *Built-in crystal oscillator for mixer local oscillator *Mixer input frequency: 10-50 MHz *Quadrature detector *On-chip bit-rate filter *Audio output *1-bit comparator with open collector output *1V regulator *1.1V low battery alarm PIN CONFIGURATIONS OSCIN 1 OSCOUT 2 MIXOUT 3 VCC IFIN DEC FSKREF IFOUT QUAD AFOUT UTC 4 5 6 7 8 9 10 11 LPFIN 12 LPFOUT 13 BS 14 CHARGE 15 FSKOUT 16 ALM 17 REGCON 18 REGOUT 19 VSS 20 MIXIN UNISONIC TECHNOLOGIES CO., LTD. 1 QW-R103-015,A UTC TA31142 NUMBER SYMBOL 1 2 3 LINEAR INTEGRATED CIRCUIT DESCRIPTION OSCIN Oscillator input (base) OSCOUT Oscillator output (emitter) MIXOUT Mixer output (2KΩ output impedance) NUMBER SYMBOL 11 12 13 4 VCC Nominal 1.4V supply 14 5 IFIN 15 6 DEC 7 FSKREF 8 IFOUT IF amplifier input (2KΩ input impedance) IF amplifier de-coupling capacitor connection 1-bit comparator reference input (requires external capacitor) IF amplifier output 9 10 QUAD AFOUT Quadrature FM demodulator input Quadrature FM demodulator output 19 20 16 17 18 DESCRIPTION LPFIN LPF operational amplifier input LPFOUT LPF operational amplifier output BS Two-state logic input to control receiver power up/down. (BS=high=normal operation; BS=low=stand-by mode) CHARGE Two-state logic input to control charge-discharge circuit. (CHARGE=high=fast charge; CHARGE=low=slow charge) FSKOUT Open collector NRZ comparator output (requires pull-up resistor) ALM Open collector low battery alarm output (requires pull-up resistor) BEGCON 1.0V regulator control output for connection to external PNP base REGOUT 1.0V regulator input for connection to external PNP collector VSS Ground MIXIN Mixer input (5KΩ input impedance) ABSOLUTE MAXIMUM RATINGS (Vss=0V ) PARAMETER SYMBOL VALUE UNIT Supply Voltage Operating temperature range Storage temperature range Soldering temperature range Soldering time range Vcc TOPR TSTG TSLD tSLD Vss-0.3 to Vss+3.5 -30 to 85 -55 to 150 255 10 V °C °C °C s RECOMMENDED OPERATING CONDITIONS (Vss=0V) PARAMETER Supply voltage range MIXIN input frequency Operating temperature UTC SYMBOL Vcc fMIXIN TA VALUE Min. 1.1 Typ. 1.35 -10 25 UNISONIC TECHNOLOGIES UNIT Max. 1.6 50 60 V MHz °C CO., LTD. 2 QW-R103-015,A UTC TA31142 LINEAR INTEGRATED CIRCUIT ELECTRICAL CHARACTERISTICS(Ta=25°C, Vcc=1.4V,Vss=0V, BS=high unless otherwise noted) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT 1.1 1.6 5 16 mA µA dB Quiescent current consumption Standby current consumption Mixer conversion gain Icc,total Icc,modby Gc Mixer output intermodulation intercept point Mixer input resistance Mixer output resistance IF amplifier input resistance S/N ratio I S/N ratio 2 S/N ratio 3 Demodulation output level AM rejection ratio FSK output duty ratio Low battery alarm threshold voltage Regulator output voltage Charging / discharging current ALM logic HIGH output current ALM logic LOW output voltage FSKOUT logic HIGH output current FSKOUT logic LOW output vlotage OIP3 -10 dBm Rin,MIX Rout,MIX Rin,IF SNI SN2 SN3 VOD AMR DR VALM 40 1.05 5 2 2 63 63 25 45 50 50 1.1 60 1.15 kΩ kΩ kΩ dB dB dB mVrms dB % V 0.95 35 1.0 70 1.05 110 2 0.4 2 V µA µA V µA 0.4 V UTC VREGOUT ICH IOH,ALM IOL,ALM IOH.FSK.OUT VBS=0V Measured after 455 KHz ceramic filter 9 -53 dBm at MIXIN -53 dBm at IFIN -91 dBm at IFIN -53 dBm at IF|N -53 dBm at IFIN AM=30% 430Ω load resistor VFSKREF=0V, VLPFOUT=0.18V VOL,PSK, 12.5 OUT UNISONIC TECHNOLOGIES CO., LTD. 3 QW-R103-015,A UTC TA31142 LINEAR INTEGRATED CIRCUIT FUNCTIONAL DESCRIPTION The UTC TA31142 IF receiver IC incorporates a mixer, crystal-based local oscillator, IF amplifier, quadrature FM demodulator, bit-rate filter, and 1–bit comparator and is capable of demodulating 2-level FSK input signals. In addition, 1.0V regulator and 1.1V low battery alarm functions are provided. POWER-DOWN FUNCTION The entire receiver IC may be powered up and down through the control of the BS input (pin13). During power down operation, the quiescent current consumption of the IC drops to approximately 0µA. The high input impedance of the BS pin allows for direct interfacing with the CMOS output of an off-chip micro controller. CHARGE / DISCHARGE CIRCUITRY The function of the charge / discharge circuitry is for both fast and slow charging / discharging of the capacitor used for storing the voltage reference level of the FSKREF pin. The CHARGE input (pin14) should be enabled (CHARGE=high=fast charge) immediately after transition of the receiver IC from power-down to normal operation in order to reduce the charging / discharging time for coarse adjustment of the FSKREF voltage to the appropriate dc level (i.e. dc level of LPFOUT pin) and consequently to minimize the erroneous output of the 1-bit comparator. During actual data reception, the CHARGE pin should be set to low (CHARGE=low=slow charge) for fine adjustment of the FSKREF voltage. 1-bit COMPARATOR The integrated 1-bit comparator operates as a data slicer and “squares up” the bit-rate filtered output from the quadrature demodulator. The decision threshold voltage level for the 1-bit comparator is stored on an external capacitor connected to the FSKREF pin. REGULATOR The on-chip 1.0V regulator requires a suitable off-chip PNP transistor to achievc regulation. The external PNP transistor should have an hFE>200 for VCE>=0.1V. LOW BATTERY ALARM The low battery alarm output, ALM, is normally low, but rises to 1.1V (=VCC) when the VCC voltage falls below approximately 1.1V. UTC UNISONIC TECHNOLOGIES CO., LTD. 4 QW-R103-015,A UTC TA31142 LINEAR INTEGRATED CIRCUIT TYPICAL CHARACTERISTICS UTC UNISONIC TECHNOLOGIES CO., LTD. 5 QW-R103-015,A UTC TA31142 LINEAR INTEGRATED CIRCUIT TEST CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 6 QW-R103-015,A