Analog Devices Inc.United States

The MAT12 is a dual, NPN-matched transistor pair that is specifically designed to meet the requirements of ultralow noise audio systems. With its extremely low input base spreading resistance (rbb' is typically 28 Ω) and high current gain (h FE typically exceeds 600 at I C = 1 mA), the MAT12 can achieve outstanding signal-to-noise ratios. The high current gain results in superior performance compared to systems incorporating commercially available monolithic amplifiers. Excellent matching of the current gain (Δh FE ) to about 0.5% and low V OS of less than 10 µV typical make the MAT12 ideal for symmetrically balanced designs, which reduce high-order amplifier harmonic distortion. Stability of the matching parameters is guaranteed by protection diodes across the base emitter junction. These diodes prevent degradation of beta and matching characteristics due to reverse biasing of the base emitter junction. The MAT12 is also an ideal choice for accurate and reliable current biasing and mirroring circuits. Furthermore, because the accuracy of a current mirror degrades exponentially with mismatches of V BE between transistor pairs, the low V OS of the MAT12 does not need offset trimming in most circuit applications. The MAT12 is a good replacement for the MAT02, and its performance and characteristics are guaranteed over the extended temperature range of −40°C to +85°C