CA/100/F Hybrid Charge Amplifier Robust, miniature, shock/vibration proof; thick film hybrid charge amplifier package; 60dB dynamic range up to 1V/pC; -50/+125.C operating range; single unregulated power supply operation, 10/30V The basis of the CA/100 is a thick film hybrid microcircuit of similar complexity to our CA/04 charge amplifier, housed in a 24 pin hermetic dip. This is packaged, together with gain controls and connectors, into a machined aluminium block, the whole constituting an extremely robust product capable of sustained operation under conditions of high vibration, mechanical shock, and temperature extremes. The CA/100, by virtue of its 60dB, 1mV/pC - 1V/pC, gain adjustment range, is an extremely flexible interface for trials type applications, allowing quite large compensatory on-line adjustment for the signal level uncertainties that may arise in this type of application. Installation should allow access to gain controls. SUPPLY VOLTAGE The CA/100 is configured for single supply, minimal current operation, and is reverse voltage protected. Supply voltage Vs may be anywhere within the range 10/30V and there is no specific need for close regulation as supply ripple rejection is of the order 60dB. However, Vs transient overvoltage protection is not included; maximum safe Vs is 36V. To maximise dynamic range the internal op amp reference bus, default value 5V, should be biased to Vs/2, requiring an add-on-test resistor. NOISE LEVEL Low current drain (2mA) conserves power resources at the expense of increased noise level, which, at 0.03pC r.t.i although some 10dB greater than that of the CA/04, is not deemed detrimental to a trials type application. GENERAL Gain controls comprise 20dB range multiturn preset potentiometer and 5 position, 10dB increment rotary switch... ...circuit ground is isolated from the housing; power signal output and housing ground connections are via 5 pole circular connector. Mounting lugs allow 2 axis fixing. ENVIRONMENTAL The CA/100 has operated satisfactorily subjected to vibration severity test level 2 for tracked vehicles (DEFSTAN 0755Pt.2), and over the temperature range -50/+125°C. Product destined for severe environmental conditions should be suitably proof tested. CA/100/F The minimum (-3dB) frequency is extended from 4Hz to 0.5Hz. This considerably increases start up/overload recovery times, exposure to transducer induced pyro-electric and strain noise, and should be selected with due regard to these possible problems. Input capacitance/1% gain reduct.nF Noise level r.t.i/p @ 1pC/g norm Single ended DJB Instruments (UK) Ltd Finchley Avenue, Mildenhall, Suffolk IP28 7BG Email [email protected] Web www.djbinstruments.com A UK company with UK-based manufacturing, assembly and calibration in-house.