ULN2204A-2B AM/FM Radio System IC PDIP-16

ULN2204A AM/FM Radio System Providing all radio functions except VHF tuning, the ULN2204A AM/FM radio system excels in low-cost applications requiring a minimal parts count and high performance. In the AM mode of operation, the device is a complete single conversion superheterodyne broadcast or shortwave receiver with AGC and peak envelope detection. In the FM mode, the ULN2204A operates as a high-gain IF amplifier/limiter and phase-shift detector. A simple dc switch is used to change the mode of operation.

A single external capacitor at pin 16 provides the AM-AGC time constant, the FM-AFC time constant, and RF decoupling. A single resistor al the same pin will adjust the AM gain for optimal system performance.

The audio amplifier will work into any speaker load of 8Ω or greater. Class-B operation of the audio power amplifier yields high efficiency at the rated output with a very low quiescent power drain. The amplifier exhibits little crossover distortion. Its output impedance is significantly less than 1Ω.

The ULN2204A will work with a wide range of supply voltages and is suitable for use in AC-powered table radios and battery-powered (6V or 9V) portable radios. This system will operate at supply voltages as low as 2V at reduced volume without a significant increase in distortion. Brown-outs or weak batteries need no longer be a major concern.

The ULN2204A is supplied in a 16-pin dual in-line plastic package with a copper lead frame that eliminates many decoupling problems and allows maximum power dissipation.

ULN2204 Pinout

ULN2204A Features

• Low Harmonic Distortion
• Wide Operating Voltage Range
• Low Power Drain
• DC AM/FM Switching
• 30 V Limiting Threshold
• Excellent AM Rejection
• Good Usable Sensitivity

ABSOLUTE MAXIMUM RATINGS AT T= +25°C

• Supply Voltage, Vcc ……………. 12V
• Package Power Dissipation, PD …………… 1W
• Operating Temperature Range, Ta …………….. -20°C to +85°C
• Storage Temperature Range, Ts ……………… -65°C to +150°C

Application

• Low-cost applications requiring a minimal parts count and high-performance

ULN2204A Datasheet