B4M1: DIP8 ±20 dB Adjustable Inverting Audio Amplifier
This is a potentiometer adjustable inverting gain stage in a DIP8 footprint for convenient breadboard prototyping. The whole module only occupies the space of a through hole dual op-amp.
Price: £11 (PCB with SMT components installed, through hole components included), £20 (+ through hole components installed)
If you have any questions please feel free to contact me via email@example.com or via Twitter (@macco_electro).
The goal for this module was to implement an adjustable gain/attenuation stage that could be adjusted without a screwdriver, in the smallest possible footprint. This module implements an inverting amplifier with gain adjustable from -20 to +20 dB. The actual circuit is shown below.
The module fits inside a DIP8 footprint whilst still including a potentiometer with an integrated knob. Typically implementing this functionality on a breadboard with discrete components would involve using a DIP8 op-amp and a through-hole potentiometer next to it (plus some TH passives). With this module it can implemented within the same footprint as just the op-amp.
Details of the dimensions are shown below.
- Width : 10.16 mm
- Depth : 10.16 mm
- Total Height : 22.3 mm
- Height Above PCB : 17.8 mm
- Weight : 2 g
- Gain range : ± 20 dB
- Bandwidth : 19 kHz
- Port impedances
- Input : 1 kΩ
- Output : <1 Ω
- Input signal range
- Upper limit: V+ + 0.1 V
- Lower limit: V- - 0.1 V
- Power supply
- Required supplies : V+, Vref, V-
- Reference voltage (Vref) : nominally (V+ - V-)/2, should match the 0 V reference of the input and output signals
- Voltage range (V+ - V-) : 2.7 to 16 V
- Quiescent current : <0.8 mA