The LM358 series consists of two independent, high gain, internally
frequency compensated operational amplifiers which were designed
specifically to operate from a single power supply over a wide range of voltages. Operation from split power
supplies is also possible and the low power supply current drain is
independent of the magnitude of the power supply voltage.
Application areas include transducer amplifiers, dc gain blocks and all the conventional op amp circuits
which now can be more easily implemented in single power supply
systems. For example, the LM358 series can be directly operated off of
the standard +5V power supply voltage which is used in digital systems
and will easily provide the required interface electronics without
requiring the additional ±15V power supplies.
Characteristics
- In the linear mode the input common-mode voltage range includes ground and the output voltage can also swing to ground, even though operated from only a single power supply voltage.
- The unity gain cross frequency is temperature compensated.
- The input bias current is also temperature compensated.
Features
- Available in 8-Bump micro SMD chip sized package
- Internally frequency compensated for unity gain
- Large dc voltage gain: 100 dB
- Wide bandwidth (unity gain): 1 MHz (temperature compensated)
- Wide power supply range: Single supply: 3V to 32V or dual supplies: ±1.5V to ±16V
- Very low supply current drain (500 µA) — essentially independent of supply voltage
- Low input offset voltage: 2 mV
- Input common-mode voltage range includes ground
- Differential input voltage range equal to the power supply voltage
- Large output voltage swing
This circuit can be used in various situations where it is necessary to amplify the audio signal of low intensity, for example: How a microphone preamplifier. This present version is mono but if you need to mount a stereo just use two equal units.
When mounting the amplifier pre check all connections and components if everything is correct, connect the circuit to a battery source or in the range 90 to 30 Volts. Apply an input signal that can be for example a microphone and then adjust the 470K trimpot until the signal level suitable for your application … The adjuster will adjust the signal from 0 to maximum volume. To make connections to the input signal and the power amplifier to use shielded cables to avoid noise.
Schematic of the audio pre-amplifier integrated circuit LM358 dual op amp
Circuit audio pre amplifier lm358 lm358 schematic 450x218 Circuit audio pre amplifier integrated circuit LM358 dual op amp
Suggested PCB mount preamp
Circuit audio pre amplifier lm358 pcb comp Circuit audio pre amplifier integrated circuit LM358 dual op amp
Suggested PCB component side: expanded by 200%
Circuit audio pre amplifier lm358 pcb Circuit audio pre amplifier integrated circuit LM358 dual op amp
Suggested PCB side of the copper
Circuit audio pre amplifier lm358 silk Circuit audio pre amplifier integrated circuit LM358 dual op ampSuggested PCB –
Silk screen components
List of material for assembly of the pre-audio amplifier IC LM358
| Part | Value |
| Capacitors | |
| C1, C2, C3, C4, C5 | 10µF/25V Capacitor electrolytic* |
| C6 | 470µF/25V Capacitor electrolytic* |
| C7 | 100nF – Capacitor ceramic |
| Semiconductors | |
| IC1 | LM358N – Low Power Dual Operational Amplifiers |
| Resistors 1/8W 5% | |
| R1, R2, R3, R4, R5 | 100k – Brown, Black, Yellow, Gold |
| R9 | 2.2k – Red, Red, Red, Gold |
| POT | 470K Trimpot horizontal mounting |
| Miscellaneous | |
| IN | Audio Input Connector |
| OUT | Audio Output Connector |
| V | Power Supply Connector |
| Other: Solder, wire, printed circuit board, IC sockets, box, power supply, etc.. | |
*We are establishing that the source is 12 to 16 Volts.
