Rapid Electronics Ltd DATA SHEET MK484 RADIO IC Description The MK484 is a monolithic integrated circuit designed in a TO92 package for use as a one chip radio solution, high sensitivity and high quality AM radio is possible with very few external components. Special features of the circuit include low supply voltage operation, the device is particularly suited to small hand-held radios. MK 484 Features § § § § Stable operation with 1.1V Low Drain Current Small and light weight (TO92 Package) Wide AGC Ranging 1 2 3 Maximum Ratings Item Operating Temperature Storage Temperature Supply Voltage Symbol Topr Tstg Vcc Rating -30 to +80 -40 to +125 1.5 Unit ºC ºC V Pin No. Symbol Description 1 2 3 Vss I/P O/P Gnd Input Output Electrical Characteristics Item Symbol Min Typ Max Unit Supply Voltage Output Voltage Drain Current Cover Range Input Resistance Total Harmonic Distortion AGC Range Power Gain VCC VOUT ICC ƒR ZIN AGC GP 1.1 0.8 150 30 - 1.4 0.3 4 4 70 1.8 1.5 3,000 - V mV mA KHz MΩ % dB dB VCC = 1.4V, RAGC = 1.5KΩ, = 1,000KHz Modulation 1,000Hz 40%, Vin = 1mV (RMS) (1) RAGC = 100 – 1.5KΩ Example Circuit This circuit provides a complete RF amplifier, Detection and AGC circuit, which requires only a few external components to give a high quality AM Tuner. Good audio quality can be achieved, and current consumption is extremely low. No setting up or alignment is required and the circuit is completely stable in use. The MK484 has an input impedance of 4MΩ and operates over a frequency range of 150KHz to 3MHz. The IC will run off a DC supply of between 1.1V and 1.8V. A current drain of 0.3mA makes it suitable for battery operation. The IC provides an output of 40 to 60 mV. MK484 RADIO IC 82-1026 The enclosed information is believed to be correct, Information may change ‘without notice’ due to product improvement. Users should ensure that the product is suitable for their use. E. & O. E. Revision B 15/02/2001 Page 1 of 2 Rapid Electronics Ltd, Severalls Lane, Colchester, Essex, England, CO4 5JS Telephone 01206 751166 Fax 01206 751188 e-mail [email protected] Cont’d.. 126pF The coil needs approximately 55 turns of 0.315mm diameter enamelled copper wire on a 100mm long ferrite rod. A process of trial and error will help you achieve the optimum number of windings on the ferrite rod. In general the thicker the wire or larger the ferrite rod diameter the fewer the number of turns required. PCB Layout for the above circuit