NJM2295A FM IF IC FOR REMOTE KEYLESS ENTRY SYSTEM ■ GENERAL DESCRIPTION The NJM2295A is FM IF IC for the remote keyless entry system (RKE). It includes almost all functions of IF blocks, from the 1st. Mixer to the wave shaving circuit. Exclusively designed NJM2295A is suited not only for the RKE, but for other FM signal receivers. ■ FEATURES ● Low Operating Current ● Low Operating Voltage ● Local Oscillation Frequency ● Mixer Active Frequency ● IF Frequency ● 1st. Mixer Included ● RSSI Circuit Included ● FSK Wave Shaping Circuit ● Bipolar Technology ● Package Outline ■ PACKAGE OUTLINE NJM2295AV 5mA typ. at V+=5V +2.7V to 7.0V 50 to 350MHz to 450MHz IF=10.7MHz SSOP20 ■ BLOCK DIAGRAM Ver.2003-12-09 -1- NJM2295A ■ ABSOLUTE MAXIMUM RATINGS PARAMETER (Ta=25°C) SYMBOL RATINGS UNIT Supply Voltage + V 9.0 V Power Dissipation PD 300 mW Operating Temperature Range Topr -40 to +85 °C Storage Temperature Range Tstg -40 to +125 °C (V+=5.0V, Ta=25°C, fmod=1kHz, fmix=320MHz, fIF=10.7MHz, fdev=±10kHz) ■ ELECTRICAL CHARACTERS PARAMETER SYMBOL TEST CONDITION + MIN. TYP. MAX. UNIT Supply Voltage V 2.7 - 7.0 V No signal Operating Current ICCq - 5.0 7.5 mA Battery saving Operating Current ICCS - - 10 µA 13.5 18.5 22.5 dB - 1 3 dB - 103 - dBµVEMF Mixer Gain 1 Gmix1 RL=No Connect. Mixer Gain 2 Gmix2 320MHz Gain - 450MHz Gain Mixer Sept Point IP Mixer Input Resistance RinM f=320MHz - 1 - kΩ Mixer Input Capacity CinM f=320kHz - 2 - pF Mixer Output Resistance ROM - 330 - Ω If amplifier Input Resistance RinIF - 330 - Ω Signal to Noise Ratio 1 S / N1 Mixer Input, VIN=80dBµVEMF - 60 - dB Signal to Noise Ratio 2 S / N2 IF input, VIN=80dBµVEMF - 60 - dB Signal to Noise Ratio 3 S / N3 IF input, VIN=35dBµVEMF - 25 - dB -3dB limiting sensitivity Slim Mixer Input - 22 27 dBµVEMF Demodulated Output Level Vod IF input, VIN=60dBµVEMF 80 150 - mVrms AM Rejection Ratio AMR IF input, VIN=80dBµVEMF, AM=30% - 50 - dB Duty ratio of Wave Shaped Output DR IF input, VIN=60dBµVEMF 40 50 60 % RSSI Output Voltage 1 RSSI1 IF input, VIN=20dBµVEMF 0.35 0.55 0.70 V RSSI Output Voltage 2 RSSI2 IF input, VIN=60dBµVEMF 0.7 1.00 1.3 V RSSI Output Voltage 3 RSSI3 IF input, VIN=100dBµVEMF 1.30 1.75 2.15 V RSSI Output Resistance RSSIR - 48 - kΩ Ich 35 70 120 µA - 0.1 0.4 V - - 2 µA Quick Charge / discharge current Low Level Output Voltage of FSK-OUT VfskL High Level Leak Current of FSK-OUT Terminal IfskH -2- IL=100µA Ver.2003-12-09 NJM2295A ■ APPLICATION CIRCUIT Ver.2003-12-09 -3- NJM2295A ■ TERMINAL FUNCTION PIN No. SYMBOL 1 OSC IN 2 OSC OUT Oscillation Output Terminal. 19 MIX IN Mixer input terminal. Input impedance : Parallel resistance : 1kΩ Parallel capacity : 2pF 4 MIX OUT 6 IF IN Limiter input terminal. Input resistance is 330Ω at typical. 7 DEC Decoupling terminal for bias. -4- FUNCTION EQUIVALENT CIRCUIT SAW is oscillation input terminal. Output terminal for mixer. Output resistance is 330Ω at typical. Ver.2003-12-09 NJM2295A ■ TERMINAL FUNCTION PIN No. SYMBOL FUNCTION 9 LIM OUT Output terminal for limiter amplifier. Typical input impedance is 300 ohms. 10 QUAD IN Input terminal of a quadrature detection circuit. Connect with a ceramic discriminator. 14 RSSI OUT RSSI output terminal. 11 AF OUT Demodulated siganl output. LPF IN Input terminal of a low pass filter. This terminal is biased from the AF-OUT terminal (11pin) through an external RC filter. 12 Ver.2003-12-09 EQUIVALENT CIRCUIT -5- NJM2295A ■ TERMINAL FUNCTION PIN No. SYMBOL 13 LPF OUT Output terminal of a low pass filter. 8 FSK REF Reference input terminal of a wave shaping comparator. Connected with an external capacitor. FSK OUT Output terminal of a wave shaping circuit. The Wave shaped signal inverted for the LPF output comes out. BS Control terminal of a battery saving circuit. H : This circuit is ON. L : This circuit is OFF. 16 CHARGE Control terminal of a quick charge / discharge circuit. H : This circuit is ON. L : This circuit is OFF. 5 V1 3 GND1 20 V2 18 GND2 17 15 + + FUNCTION EQUIVALENT CIRCUIT On and ;after IF supply voltage. - On and after IF ground. - Supply voltage for mixer and OSC. - Ground for mixer and OSC - [CAUTION] The specifications on this databook are only given for information , without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights. -6- Ver.2003-12-09