CXA1994AM/BM M-ary FSK Demodulating Comparator For the availability of this product, please contact the sales office. Description The CXA1994AM/BM is a comparator which allows the M-ary (4-level) FSK data to be demodulated in combination with an FM IF amplifier for pagers. Features • Low power consumption 70µA (at VCC = 1.4V, including the current on battery saving control pin) • Low voltage operation VCC = 1.0 to 4.0V Applications M-ary FSK pagers 8 pin SOP (Plastic) Absolute Maximum Ratings (Ta = 25°C) • Supply voltage VCC 7.0 • Operating temperature Topr –20 to +75 • Storage temperature Tstg –65 to +150 Operating Conditions • Supply voltage Function • Window comparator for MSB detection • Battery saving control pin • Threshold level adjustment pin VCC V °C °C 1.0 to 4.0 V B.S. GND NC DATA OUT 8 7 6 5 1 2 3 4 VCC TH CONT DATA IN REF Block Diagram Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits. –1– E96428A8Y CXA1994AM/BM Pin Description Pin No. 1 Symbol VCC Pin voltage Equivalent circuit Description 1.5V Vcc. VCC 2 TH CONT — Adjusts the threshold level for comparator. 2 GND VCC 3 DATA IN Signal input. Connected to the COMP IN pin of the CXA1484A. 0.2V 3 GND 4 REF 0.2V Reference input. Connected to the SENSE pin of the CXA1484A. 4 5 5 DATA OUT Comparator output. — GND 6 NC — 7 GND 0 Ground. VCC 8 B.S. — 8 Battery saving control. GND –2– CXA1994AM/BM Electrical Characteristics Item (VCC = 1.4V, Ta = 25°C) Symbol Condition Min. Typ. Max. Unit 70 100 µA 6 µA Current consumption ICC Current consumption ICCS Comparator input voltage high level VCOMPH VREF as a reference 50 mV Comparator input voltage low level VCOMPL VREF as a reference –50 mV Comparator output saturation voltage Vsat Logic input voltage high level VTHH Logic input voltage low level VTHL 0.4 0.9 V V 0.35 V Pin Description 1. VCC 2. TH CONT 3. DATA IN 4. REF 5. DATA OUT 6. NC 7. GND 8. B.S. Power supply pin of 1V or more This pin adjusts the threshold level and the default is approximately ±50mV from the reference voltage. The threshold level can be set lower by inserting a resistor between VCC and this pin. (The level cannot be set higher.) The signal after passing through the data filter of the IF IC (CXA1484A) is input. Connects to the reference voltage pin of the IF IC. (Pin 15 of the CXA1484A) Comparator output. Not connected. Ground. Battery saving control pin. Battery saving state for low; normal operation for high. –3– CXA1994AM/BM Electrical Characteristics Measurement Circuit B.S. control DATA OUT 8 7 6 5 CXA1994AM/BM 1 2 4 3 VCC 1V to 4V REF [from REF (0.2V) IF of IC] 0.01µ 5.1k 1µ DATA IN [from DATA (DC 0.2V) of IF IC] ∗ The comparator level can be set lower by inserting a resistor between Pin 1 (VCC) and Pin 2. –4– VCC = 1.0 to 4.0 C2 10p to 120p Application Circuit XTAL C3 0.01µ 1.8µ L1 –5– C5 15p C4 22p OSC 2 MIX 19 CXA1484A 1 20 GND 17 C6 10µ 4 C8 10µ PNP C7 0.01µ 5 IF LIM VB REG 16 6 15 S2 7 R6 33k CHARGE 9 11 GND R12 43k C12 2200p R11 43k C11 0.01µ GND R10 43k 10 OP AMP R8 43k Ceramic Discriminator R9 43k QUAD DET 8 12 OP AMP 13 C10 2200P R7 43k GND C14 10µ C13 0.01µ 1 8 C15 0.01µ 2 7 GND 3 6 4 5 CXA1994AM/BM R14 47k DATA OUT Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same. GND S F 14 NRZ COMP GND C9 10µ GND NRZ OUT R5 47k C16 0.1µ REG OUT R4 GND 75k SENSE R3 22k GND REG BS S1 LVA CERAFIL 3 18 R2 47k GND A S LVA OUT CXA1994AM/BM CXA1994AM/BM Description of Operation M-ary (M = 2- or 4-level) FSK emodulation system Polarity discrimination output and MSB comparator output are used to demodulate the 4-level waveform shown below. 4-level FSK demodulating waveform +4.8kHz +1.6kHz –1.6kHz 01 00 10 11 01 10 00 –4.8kHz Polarity discrimination output POS 0 0 1 1 0 1 0 1 0 0 1 1 0 0 NEG MSB comparator output 1.6kHz 4.8kHz The 4-level FSK demodulating data is divided into a polarity discrimination output and a MSB comparator output shown above. Here, the polarity discrimination output corresponds to a conventional NRZ comparator output. The MSB comparator output is made comparing to the optional level setting between MSB and LSB levels as reference. For the 2-level FSK demodulation, it corresponds to a conventional NRZ comparator output. Take care that the polarity of NRZ output is inverted in CXA1484A. –6– CXA1994AM/BM Example of Representative Characteristics Threshold level change 50 VCC = 1.4V 40 30 H → L threshold level 20 Threshold level [mV] L → H threshold level 10 0 –10 L → H threshold level –20 –30 H → L threshold level –40 –50 10 20 30 40 Resistance between Pins 1 and 2 [kΩ] Threshold level temperature characteristics 80 60 40 Threshold level [mV] VCC = 1.4V H → L threshold level L → H threshold level 20 0 –20 L → H threshold level –40 –60 –80 H → L threshold level –20 0 20 Temperature [°C] –7– 40 60 80 CXA1994AM/BM Package Outline Unit : mm CXA1994AM 8PIN SOP (PLASTIC) + 0.4 1.25 – 0.15 + 0.4 5.0 – 0.1 8 0.10 5 6.4 ± 0.4 + 0.3 4.4 – 0.1 A 4 1 1.27 b 0.24 M + 0.15 0.1 – 0.1 0.5 ± 0.2 B b = 0.4 ± 0.03 DETAIL B : SOLDER + 0.03 0.15 – 0.01 (0.4) (0.15) + 0.1 0.15 – 0.05 0° to 10° + 0.1 b = 0.4 – 0.05 DETAILA DETAIL B : PALLADIUM PACKAGE STRUCTURE PACKAGE MATERIAL EPOXY RESIN SONY CODE SOP-8P-L03 LEAD TREATMENT SOLDER/PALLADIUM PLATING EIAJ CODE SOP008-P-0225 LEAD MATERIAL 42/COPPER ALLOY PACKAGE MASS 0.1g JEDEC CODE NOTE : PALLADIUM PLATING This product uses S-PdPPF (Sony Spec.-Palladium Pre-Plated Lead Frame). CXA1994BM 8PIN SOP (PLASTIC) 300mil + 0.4 1.85 – 0.15 + 0.4 6.1 – 0.1 8 5 6.9 4 0.5 ± 0.2 1 + 0.2 0.1 – 0.05 7.9 ± 0.4 + 0.3 5.3 – 0.1 0.15 + 0.1 0.2 – 0.05 0.45 ± 0.1 1.27 ± 0.12 M PACKAGE STRUCTURE PACKAGE MATERIAL EPOXY RESIN SONY CODE SOP-8P-L01 LEAD TREATMENT SOLDER PLATING EIAJ CODE ∗SOP008-P-0300-A LEAD MATERIAL COPPER / 42 ALLOY PACKAGE WEIGHT 0.1g JEDEC CODE –8–