TA31142

TA31142 UTC | Alldatasheet

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UTC TA31142 LINEAR INTEGRATED CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 1 QW-R103-015,A 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

*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 TSSOP-20 PIN CONFIGURATIONS OSCIN 1 OSCOUT MIXOUT VCC IFIN DEC FSKREF QUAD IFOUT AFOUT LPFIN11 LPFOUT BS CHARGE FSKOUT ALM REGCON VSS REGOUT MIXIN

UTC TA31142 LINEAR INTEGRATED CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 2 QW-R103-015,A NUMBER SYMBOL DESCRIPTION NUMBER SYMBOL DESCRIPTION

1 OSCIN Oscillator input (base) 11 LPFIN LPF operational amplifier input

2 OSCOUT Oscillator output (emitter) 12 LPFOUT LPF operational amplifier output

3 MIXOUT Mixer output (2KΩ output

impedance)

13 BS Two-state logic input to control

receiver power up/down. (BS=high=normal operation; BS=low=stand-by mode) 4 VCC Nominal 1.4V supply 14 CHARGE Two-state logic input to control charge-discharge circuit. (CHARGE=high=fast charge; CHARGE=low=slow charge)

5 IFIN IF amplifier input (2KΩ input

impedance)

15 FSKOUT Open collector NRZ comparator

output (requires pull-up resistor)

6 DEC IF amplifier de-coupling capacitor

16 ALM Open collector low battery alarm

output (requires pull-up resistor)

7 FSKREF 1-bit comparator reference input

(requires external capacitor) 17 BEGCON 1.0V regulator control output for connection to external PNP base 8 IFOUT IF amplifier output 18 REGOUT 1.0V regulator input for connection to external PNP collector

9 QUAD Quadrature FM demodulator input 19 VSS Ground

10 AFOUT Quadrature FM demodulator

20 MIXIN Mixer input (5KΩ input

impedance) ABSOLUTE MAXIMUM RATINGS (Vss=0V ) PARAMETER SYMBOL VALUE UNIT Supply Voltage Vcc Vss-0.3 to Vss+3.5 V Operating temperature range T OPR -30 to 85 °C Storage temperature range T STG -55 to 150 °C Soldering temperature range T SLD 255 °C Soldering time range t SLD 10 s RECOMMENDED OPERATING CONDITIONS (Vss=0V) PARAMETER SYMBOL VALUE UNIT Min. Typ. Max. Supply voltage range Vcc 1.1 1.35 1.6 V MIXIN input frequency f MIXIN 50 MHz Operating temperature T A -10 25 60 °C

UTC TA31142 LINEAR INTEGRATED CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 3 QW-R103-015,A ELECTRICAL CHARACTERISTICS(Ta=25°C, Vcc=1.4V,Vss=0V, BS=high unless otherwise noted) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT Quiescent current consumption Icc, total 1.1 1.6 mA Standby current consumption Icc, modby V BS=0V 5 µA Mixer conversion gain Gc Measured after 455 KHz ceramic filter 9 12.5 16 dB Mixer output intermodulation intercept point OIP3 -10 dBm Mixer input resistance R in,MIX 5 kΩ Mixer output resistance R out,MIX 2 kΩ IF amplifier input resistance R in,IF 2 kΩ S/N ratio I SNI -53 dBm at MIXIN 63 dB S/N ratio 2 SN2 -53 dBm at IFIN 63 dB S/N ratio 3 SN3 -91 dBm at IFIN 25 dB Demodulation output level VOD -53 dBm at IF|N 45 mVrms AM rejection ratio AMR -53 dBm at IFIN AM=30% 50 dB FSK output duty ratio DR 40 50 60 % Low battery alarm threshold voltage VALM 1.05 1.1 1.15 V Regulator output voltage V REGOUT 430Ω load resistor 0.95 1.0 1.05 V Charging / discharging current I CH V FSKREF=0V, VLPFOUT=0.18V 35 70 110 µA ALM logic HIGH output current I OH,ALM 2 µA ALM logic LOW output voltage I OL,ALM 0.4 V FSKOUT logic HIGH output current IOH.FSK.OUT 2 µA FSKOUT logic LOW output vlotage VOL,PSK, OUT 0.4 V

UTC TA31142 LINEAR INTEGRATED CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 4 QW-R103-015,A 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 TA31142 LINEAR INTEGRATED CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 5 QW-R103-015,A TYPICAL CHARACTERISTICS

UTC TA31142 LINEAR INTEGRATED CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 6 QW-R103-015,A TEST CIRCUIT