RoHS Compliance Information	Size in Kbytes	Date
CLC5509 Ultra Low Noise Preamplifier	458 Kbytes	26-Mar-01	Download
CLC5509 Ultra Low Noise Preamplifier (Japanese)	229 Kbytes

Obsolete Versions

General Description

The CLC5509 is a high performance, ultra low noise preamplifier designed for applications requiring unconditional stability for wide ranges of complex input loads. Both input impedance and gain are externally adjustable, which make it simple to interface to peizoelectric ultrasound transducers. The CLC5509 preamplifier's low 0.58nV total input noise makes it ideal for noise sensitive front ends. The high repeatability in group delay over voltage and temperature translates into precision edge measurements for Doppler applications.

The IC consists of an emitter input, common base amplifier stage followed by a low distortion, closed loop buffer. The Noise Figure can be user programmed by controlling the emitter current (I_BIAS1) which sets emitter resistance r_e. External negative feedback creates a well controlled input impedance to allow a near noiseless active input transmission line termination. The preamp is stable against changes in source impedance of 50 to 200 over temperature and supply variations, with gains from 14dB to 26dB. The CLC5509 preamp architecture is also well suited for use with magneto-resistive tape or disk drive heads. In these applications the head bias current can be reused to bias the preamp. The part is packaged in an 8-pin plastic SOIC, and runs off ±5V supplies. External biasing is required for the input signal path.

The CLC5509 is constructed using an advanced complementary bipolar process and National Semiconductor's proven high performance architectures.

More Application Notes

Title	Size in Kbytes	Date
AN-1138: Application Note 1138 CLC5506 Evaluation Board	124 Kbytes	4-Oct-04	Download