Pedal Parts / DIY

LM358 dual op amp in an 8-pin DIP package. These devices consist of two independent, high-gain, frequency-compensated operational amplifiers designed to operate from a single supply over a wide range of voltages. Operation from split supplies also is possible if the difference between the two supplies is 3 V to 32 V (3 V to 26 V for the LM2904), and VCC is at least 1.5 V more positive than the input common-mode voltage. The low supply-current drain is independent of the magnitude of the supply voltage. Applications include transducer amplifiers, dc amplification blocks, and all the conventional operational amplifier circuits that now can be implemented more easily in single-supply-voltage systems.

LM358H dual op amp in an 8-pin TO-99 package. The LM358H 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.

LM380 power amp in a 14-pin DIP package. The LM380 is a power audio amplifier for consumer applications. In order to hold system cost to a minimum, gain is internally fixed at 34 dB. A unique input stage allows ground referenced input signals. The output automatically self-centers to one-half the supply voltage. The output is short circuit proof with internal thermal limiting. The package outline is standard dual-in-line. The LM380N uses a copper lead frame. The center three pins on either side comprise a heat sink.

LM386 Low Voltage Audio Power Amplifier The LM386 is a mono low voltage amplifier that can be used in a variety of applications. It can drive loads from 4 Ω to 32 Ω. The gain is internally set to 20 but it can be modified from 20 to 200 by placing a resistor and capacitor between pins 1 and 8. As this is an Op Amp it can be used in different configurations to fit in several applications. The internal gain setting resistor allows the LM386 to be used in a very low part count system. In addition a series resistor can be placed between pins 1 and 5 to modify the gain and frequency response for specific applications. These are found in many small audio amplifiers and even tiny pedal sized guitar amplifiers! There are tons of possibilities for this little Op Amp.

LM3900 quad op amp in a 14-pin DIP package. These devices consist of four independent, high-gain frequency-compensated Norton operational amplifiers that were designed specifically to operate from a single supply over a wide range of voltages. Operation from split supplies is also possible. The low supply current drain is essentially independent of the magnitude of the supply voltage. These devices provide wide band- width and large output voltage swing. Features

• Wide Range of Supply Voltages, Single or Dual Supplies
• Wide Bandwidth
• Large Output Voltage Swing
• Output Short-Circuit Protection
• Internal Frequency Compensation
• Low Input Bias Current
• Designed to Be Interchangeable With National Semiconductor LM2900 and LM3900, Respectively

LM741 single opamp in an 8-pin DIP package. The LM741 has been used in classic guitar pedals such as the Distortion Plus.
The LM741 series are general purpose operational amplifiers which feature improved performance over industry standards like the LM709. They are direct, plug-in replacements for the 709C, LM201, MC1439 and 748 in most applications. The amplifiers offer many features which make their application nearly foolproof: overload protection on the input and output, no latch-up when the common mode range is exceeded, as well as freedom from oscillations.

LM833 dual op amp in an 8-pin dip package. The LM833 is a dual general purpose operational amplifier designed with particular emphasis on performance in audio systems. This dual amplifier IC utilizes new circuit and processing techniques to deliver low noise, high speed and wide bandwidth without increasing external components or decreasing stability. The LM833 is internally compensated for all closed loop gains and is therefore optimized for all preamp and high level stages in PCM and HiFi systems. The LM833 is pin-for-pin compatible with industry standard dual operational amplifiers. Features

• Wide dynamic range: >140dB
• Low input noise voltage: 4.5nV/ √ ^Hz
• High slew rate: 7 V/μs (typ); 5V/μs (min)
• High gain bandwidth: 15MHz (typ); 10MHz (min)
• Wide power bandwidth: 120KHz
• Low distortion: 0.002%
• Low offset voltage: 0.3mV
• Large phase margin: 60°

LT1054 switched-capacitor voltage converter with regulator in an 8 pin DIP package. The LT1054 device is a bipolar, switched-capacitor voltage converter with regulator. It provides higher output current and significantly lower voltage losses than previously available converters. An adaptive-switch drive scheme optimizes efficiency over a wide range of output currents. Total voltage drop at 100-mA output current typically is 1.1 V. This applies to the full supply-voltage range of 3.5 V to 15 V. Quiescent current typically is 2.5 mA. The LT1054 also provides regulation, a feature previously not available in switched-capacitor voltage converters. By adding an external resistive divider, a regulated output can be obtained. This output is regulated against changes in both input voltage and output current. The LT1054 can also shut down by grounding the feedback terminal.

The NJM2120 is a dual operational amplifier of 2-INPUT and 1-OUTPUT with analog switch. The NJM2120 can be used as analog switch under the condition of GV=0dB, as Switch + Amp in order that each gain (A or B) can be adjusted independently. Each amplifier of the NJM2120 has the same electrical characteristics as the NJM4558. The NJM2120 is suitable for audio, video, electrical musical instrument, etc.

5V linear regulator with up to 1 amp of current in a TO-220 package. This style of regulator can be found in many power supplies and also modular synth circuits as well as some stomp boxes. These voltage regulators are monolithic integrated circuits designed as fixed−voltage regulators for a wide variety of applications including local, on−card regulation. These regulators employ internal current limiting, thermal shutdown, and safe−area compensation. With adequate heatsinking they can deliver output currents in excess of 1.0 A. Although designed primarily as a fixed voltage regulator, these devices can be used with external components to obtain adjustable voltages and currents.

MC78L05 5V Linear Regulator. Used in MOD® kits. The TI version is the LM78L05. This fixed-voltage monolithic integrated circuit voltage regulator is suitable for applications that required supply current up to 100 mA.

NPN Darlington transistor (TO-92 package) - designed for applications requiring extremely high current gain at collector currents to 1.0A.

• Max collector to emitter voltage = 30 V
• Max collector to base voltage = 30 V
• Max emitter to base voltage = 10 V
• Max collector current = 1.2 A (continuous)

MPSA14 NPN Darlington transistor (TO-92 package) - designed for high gain, low noise general purpose amplifier applications.

• Max collector to emitter voltage = 30 V
• Max collector to base voltage = 30 V
• Max emitter to base voltage = 10 V
• Max collector current = 0.5 A (continuous)

NPN low noise transistor (TO-92 package) - designed for high gain, low noise general purpose amplifier applications.

• Max collector to emitter voltage = 45 V
• Max collector to base voltage = 45 V
• Max emitter to base voltage = 6.5 V
• Max collector current = 0.2 A (continuous)

MPSA63 PNP Darlington transistor (TO-92 package) - designed for high gain, low noise general purpose amplifier applications.

• Max collector to emitter voltage = -30V
• Max collector to base voltage = -30 V
• Max emitter to base voltage = -10 V
• Max collector current = -0.5 A (continuous)

MPSA63 PNP Darlington transistor (TO-92 package) - designed for high gain, low noise general purpose amplifier applications.

• Max collector to emitter voltage = -30V
• Max collector to base voltage = -30 V
• Max emitter to base voltage = -10 V
• Max collector current = -0.5 A (continuous)

The NJM5532 is a high performance dual low noise operational amplifier. Compared to the standard dual operational amplifiers, such as the NJM1458, it shows better noise performance, improved output drive capability, and considerably higher small-signal and power bandwidths. it is compensated internally for voltage follower circuit. This makes the device especially suitable for application in high quality and professional audio equipment, instrumentation, control circuits, and telephone channel amplifiers Features:

• Operating Voltage = ±3V~±22V
• Small Signal Bandwidth = 10MHz typ.
• Output Drive Capability = 600Ω,10Vrms typ.
• Input Noise Voltage = 5nV/√Hz typ.
• Power Bandwidth = 140kHz typ.
• Slew Rate = 8V/µs typ.
• Bipolar Technology

NE5532 dual op amp in an 8-pin DIP package. The NE5532 device is a high-performance operational amplifier combining excellent DC and AC characteristics. They feature very low noise, high output-drive capability, high unity-gain and maximum-output-swing bandwidths, low distortion, high slew rate, input-protection diodes, and output short-circuit protection. These operational amplifiers are compensated internally for unity-gain operation. These devices have specified maximum limits for equivalent input noise voltage. Features

• Equivalent Input Noise Voltage: 5 nV/√Hz Typ at 1 kHz
• Unity-Gain Bandwidth: 10 MHz Typ
• Common-Mode Rejection Ratio: 100 dB Typ
• High DC Voltage Gain: 100 V/mV Typ
• Peak-to-Peak Output Voltage Swing 26 V Typ With VCC± = ±15 V and RL = 600 Ω
• High Slew Rate: 9 V/μs Typ

NE5534 single op amp in an 8-pin DIP package. The NE5534 device is a high-performance operational amplifier combining excellent dc and ac characteristics. Some of the features include very low noise, high output-drive capability, high unity-gain and maximum-output-swing bandwidths, low distortion, and high slew rate. These operational amplifiers are compensated internally for a gain equal to or greater than three. Optimization of the frequency response for various applications can be obtained by use of an external compensation capacitor between COMP and COMP/BAL.

NJM4558L dual op amp from JRC in a SIP8 package. The NJM4558L is the same as the DIP NJM4558 (JRC4558) otherwise. The SIP version is a great replacement for dual op amps in vintage circuits as well as a space saving package for some PCB layouts. The NJM4558L is a dual high-gain operational amplifier with internal compensation circuit and constructed on a single silicon chip. It offers excellent characteristics by combining the parameters adjusted for a monolithic chip. The channel separation characteristic is suitable for measuring instruments. Features:

• Operating Voltage ( ±4V~±18V )
• High Voltage Gain ( 100dB typ. )
• High Input Resistance ( 5MΩ typ. )
• Bipolar Technology

See P-Q4558 for the DIP version of this chip

NJM4580L dual op amp from JRC in a SIP8 package. The NJM4580L is the same as the DIP NJM4580 (JRC4580) otherwise. The SIP version is a great replacement for dual op amps in vintage circuits as well as a space saving package for some PCB layouts. The NJM4580 is a dual operational amplifier, specially designed for improving the tone control, which is most suitable for the audio application. Featuring noiseless, higher gain bandwidth, high output current and low distortion ratio, and it is most suitable not only for acoustic electronic parts of audio pre-amp and active filter, but also for the industrial measurement tools.

NOS OA74A germanium diodes from Amperex. OA74A diodes were used in many vintage electronics and also make for great clipping diodes in stompbox effects pedals. The red end is the cathode. OA74A is a near-exact replacement for OA81.

OC139 NPN germanium transistors. The OC139 is a popular NPN for fuzz pedals and boost effects. This transistor is in a glass SO-2 package with long leads commonly found on germanium transistors. The NPN polarity allows for use with standard pedal power supplies. The dot indicates the collector lead. The OC139 can be found in the EarthQuaker Devices Bows germanium preamp.

OC43 PNP germanium transistors. The OC43 is a popular PNP for fuzz pedals and boost effects. This transistor is in a glass SO-2 package with long leads commonly found on germanium transistors. The dot indicates the collector lead.