U2535B

U2535B Preamplifier for IR Remote Control Description The IC U2535B is a complete IR receiver for data communication. The PIN photodiode converts the transmitted IR telegram into electronic input signals. This is separated by a special input circuit. The characteristics (filter, gain) of the following amplifier are determined by external components. The signal detector, consisting of a comparator, an integrator and a Schmitt trigger, forms the input signal to an output pulse that can be interfaced to a microcomputer. Features D Low current requirement (typical 260 mA/ 12 V) D Carrier frequencies 20 to 100 kHz D Supply voltages: 5 or 7 to 16 V with internal stabilization Applications D Keyless entry D Remote control D Wireless data transfer D Filter characteristics and gain are specified by few external components D Demodulator with Schmitt trigger D Open collector output Ordering Information Extended Type Number U2535B-FP Package SO8 Remarks Block Diagram 95 9958 5 VS Supply voltage for PIN diode 7 IN 8 – + +VCC + – 4 + – Integrator OSW VS1 1 kW 10 mF +V 10 mF 6 GND A1 C1 1 R1 2 A0 C2 3 C3 C3 R2 Figure 1. Block diagram Rev. A2, 15-Oct-98 1 (6) U2535B Pin Description AI AO C3 OSW 1 8 Pin 1 IN Symbol Function AI Inverting input of bandpass amplifier, pin connection for external filter function AO Output of bandpass amplifier C3 Capacitor at Pin 3 to reject (suppress) ripple during transmission, also functions as delay time for reference voltage of the comparator OSW Switching output Open collector output which switches with time delay and turns to LOW (transistor switched ON) when the signal is identified at Pin 2. VS Supply voltage The integrated Z-diode (typically 17 V) protects the circuit against positive voltage spikes GND Ground VS1 Unregulated supply voltage for 5 V operation IN Input connection for photodiode with regulated bias voltage 2 3 2 7 VS1 GND 4 3 6 4 95 10323 5 VS Figure 2. Pinning 5 6 7 8 Absolute Maximum Ratings Reference point Pin 6, unless otherwise specified Parameters Supply-voltage range Pin 5 Supply currents: Pin 5 tp ≤ 250 ms Pin 5 Input voltages Pin 1 Pin 4 Pin 8 Output currents Pins 2 and 4 Junction temperature Storage-temperature range Ambient-temperature range Symbol VS IS iS VA(I) V0(SW) VIN I0 Tj Tstg Tamb Value –0.3 to +16 20 150 –0.3 to 5 –0.3 to 16 –0.3 to 5 ±5 125 –40 to +125 –40 to +105 Unit V mA mA V V V mA °C °C °C Thermal Resistance Parameters Junction ambient Symbol RthJA Value 180 Unit K/W 2 (6) Rev. A2, 15-Oct-98 Preliminary Information U2535B Electrical Characteristics Tamb = 25°C, reference point Pin 6, test circuit, unless otherwise specified Parameters Supply currents Internal stabilization Maximum input current Low-level voltage Leakage current Input stage, amplifier Cut-off frequency Gain Test Conditions / Pins VS1 = 5 V, IIN = 0, Pin 7 Pin 5 VS = 12 V, IIN =0, VS = 12 V, IIN = 0, Pin 7 VS1 = 5 V, VIN = 0, Pin 8 VS1 = 5 V, IOL = 0.5 mA Pin 4 VS1 = 5 V, V0 = 12 V, Pin 4 Symbol IS1 IS VS1 –IIN VOL IOH fL fH vi = 2 mVrms, f = 40 kHz f = 100 kHz td ≤ 200 ms, f = 40 kHz, Pin 2 f = 40 kHz, VA0 = 1 Vrms see figure 4 f = 40 kHz, VA0 = 1 Vrms see figure 4 Gv Gv VA0 td ts 50 100 Min. 140 200 4.9 0.8 Typ. Max. 200 320 5.4 1.2 0.2 1 15 100 47 46 50 49 150 90 150 Unit mA mA V mA V mA kHz kHz dB dB mVrms Detector Threshold voltage Delay time Storage time ms ms Test Circuit 95 9959 7 300 kW Ri Vi 5 C2 IIN 1 2 300 kW R1 Ci 100 nF 1 kW R2 C3 22 nF 3 8 +5 V 47 kW U2535B 4 Output 6 10 nF Figure 3. Test circuit Rev. A2, 15-Oct-98 3 (6) U2535B 95 9960 V VAO VL td 400 T ts t Figure 4. Waveforms for td and ts measurement Application Circuit 10 mF 10 mF +12 V 1 kW 8 7 6 5 U2535B 95 9961 1 300 kW C1 680 pF R2 1.2 kW R1 2 3 4 mC C2 100 pF C3 47 nF 22 kW + Figure 5. Application circuit 4 (6) Rev. A2, 15-Oct-98 Preliminary Information U2535B Bandpass Filter Design Center frequency fO + 2p R1 1 1 C1 1 R2 C2 R1 >> R2 C1 C2 GAIN [ R R(C )C C ) 2 1 2 y Bandwidth [ 2p C1 R1 )C 2 C1 C2 BW