# Transistors

Transistor - AS194H, Matched Pair, Alfa, TO5-8 case, NPN
The AS194H is a junction isolated ultra well-matched monolithic NPN transistor pair with an order of magnitude improvement in matching over conventional transistor pairs. Electrical characteristics of these devices such as drift versus initial offset voltage, noise, and the exponential relationship of base-emitter voltage to collector current closely approach those of a theoretical transistor. Extrinsic base and emitter resistances are very low, giving very low noise and operating over a wide current range. To guarantee long term stability of matching parameters, internal clamp diodes have been added across the emitter-base junction of each transistor. These prevent degradation due to reverse biased emitter current, the most common cause of field failures in matched devices.
$4.50 Transistor - AS3046, Array of 5, Matched Pair, 14-Pin DIP, NPN The AS3046 is Alfa’s version of the CA3046 (LM3046) IC. The AS3046 consists of five general purpose silicon NPN transistors on a common monolithic substrate. Two of the transistors are internally connected to form a differentially-connected pair. The transistors are well suited to a wide variety of applications in low power systems. They may be used as discrete transistors in conventional circuits however, in addition, they provide the very significant inherent integrated circuit advantages of close electrical and thermal matching. The AS3046 is available in a 14-pin DIP package. Features • Matched pair of npn transistors • VBE matched less than ±1 mV • 5 general purpose monolithic transistors • Wide operating current range Applications • Filters • Custom designed differential amplifiers • Temperature compensated amplifiers$3.99
Transistor Set - tested and selected for Fuzz Face, 2N1309, PNP, Germanium
This is a set of two 2N1309 germanium transistors that have been hand-selected to work in the germanium Fuzz Face circuit. Also included are 4 metal film resistors to use in the circuit. In most cases, the values have been modified from the stock values slightly to ensure that the collector of Q2 biases to roughly -4.5V. A data sheet containing the schematic and the resistor values is included so that you can use your own resistor type if you would prefer. There is a range of bias voltages that can sound nice in a Fuzz Face, and voltages in original units varied. These transistors have been tested with bias voltage, sound, and noise level in mind. Note that due to a variety of factors such as battery/PSU voltage, temperature, and component tolerance, the voltage on the collector of Q2 may not measure at exactly -4.5V, but it should be close in a properly-built circuit.
$24.95 Transistor - AS395H, Matched Pair, Alfa, TO5-8 case, PNP The AS395 dual monolithic PNP transistor offers excellent parametric matching and high frequency performance. Low noise characteristics (1 nV/√Hz typ @ 1 kHz), high bandwidth (190 MHz typical), and low offset voltage (100 µV max), makes the AS395 an excellent choice for demanding preamplifier applications.Tight current gain matching (3% max mismatch) and high current gain (100 min), over a wide range of collector current, makes the AS395 an excellent choice for current mirrors. A low value of bulk resistance makes the AS395 an ideal component for applications requiring accurate logarithmic conformance. To ensure the long-term stability of the matching parameters, internal protection diodes across the base-emitter junction clamp any reverse base-emitter junction potential.$5.50
Transistor - AS394H, Matched Pair, Alfa, TO5-8 case, NPN
The AS394H is a junction isolated ultra well-matched monolithic NPN transistor pair with an order of magnitude improvement in matching over conventional transistor pairs. Electrical characteristics of these devices such as drift versus initial offset voltage, noise, and the exponential relationship of base-emitter voltage to collector current closely approach those of a theoretical transistor. Extrinsic base and emitter resistances are very low, giving very low noise and operating over a wide current range. To guarantee long term stability of matching parameters, internal clamp diodes have been added across the emitter-base junction of each transistor. These prevent degradation due to reverse biased emitter current, the most common cause of field failures in matched devices.
$4.25 Transistor - AS394CH, Matched Pair, Alfa, TO5-8 case, NPN The AS394CH is a junction isolated ultra well-matched monolithic NPN transistor pair with an order of magnitude improvement in matching over conventional transistor pairs. Electrical characteristics of these devices such as drift versus initial offset voltage, noise, and the exponential relationship of base-emitter voltage to collector current closely approach those of a theoretical transistor. Extrinsic base and emitter resistances are very low, giving very low noise and operating over a wide current range. To guarantee long term stability of matching parameters, internal clamp diodes have been added across the emitter-base junction of each transistor. These prevent degradation due to reverse biased emitter current, the most common cause of field failures in matched devices.$4.95
Transistor - AS194DE, Matched Pair, Alfa, SOIC-8, NPN
The AS194DE is a junction isolated ultra well-matched monolithic NPN transistor pair with an order of magnitude improvement in matching over conventional transistor pairs. Electrical characteristics of these devices such as drift versus initial offset voltage, noise, and the exponential relationship of base-emitter voltage to collector current closely approach those of a theoretical transistor. Extrinsic base and emitter resistances are very low, giving very low noise and operating over a wide current range. To guarantee long term stability of matching parameters, internal clamp diodes have been added across the emitter-base junction of each transistor. These prevent degradation due to reverse biased emitter current, the most common cause of field failures in matched devices.
$4.50 Transistor - AS3046D, Array of 5, Matched Pair, SOIC-14, NPN The AS3046 is Alfa’s version of the CA3046 IC in an SOIC package. The AS3046D consists of five general purpose silicon NPN transistors on a common monolithic substrate. Two of the transistors are internally connected to form a differentially-connected pair. The transistors are well suited to a wide variety of applications in low power systems. They may be used as discrete transistors in conventional circuits however, in addition, they provide the very significant inherent integrated circuit advantages of close electrical and thermal matching. The AS3046D is available in a 14-pin SOIC package. Features • Matched pair of npn transistors • VBE matched less than ±1 mV • 5 general purpose monolithic transistors • Wide operating current range Applications • Filters • Custom designed differential amplifiers • Temperature compensated amplifiers$3.95