THAT 4311
Low-voltage Low-power Analog Engine^® Dynamics Processor IC

IMPORTANT:
The 4311 is not recommended for new designs
for your new circuits designs see our 4320 Low-Power Analog Engine ICs.

	Simple compressor / limiter using the THAT 4311

The THAT 4311 Low Power Dynamics Processor combines in a single IC all the active circuitry needed to construct a wide range of dynamics processors that operate off of as little as 0 - 5 Volts. The 4311 includes a high performance, Blackmer® voltage controlled amplifier, a log responding RMS-level sensor and three opamps, one of which is dedicated to the VCA, while the other two may be used for the signal path or control voltage processing.

 The exponentially-controlled VCA provides two opposing-polarity, voltage sensitive control ports. Dynamic range exceeds 105 dB, and the post-trim THD is typically 0.09% at 0dB gain. The RMS detector provides accurate RMS to DC conversion over an 80 dB dynamic range.

 Though originally designed for use in microphone noise reduction systems, the 4311 is a useful building block in a number of analog signal processing applications. The combination of exponential VCA gain control and logarithmic detector response - “decibel-linear” response - simplifies the mathematics of designing the control paths of dynamics processors, making it easy to develop audio compressors, limiters, gates, expanders, de-essers, duckers, and the like. The high level of integration ensures excellent temperature tracking between the VCA and the detector, while minimizing the external parts count.

Features High Performance Blackmer VCA, RMS-Level Detector, and three Opamps in one package Wide Dynamic Range: > 105 dB Low THD: < 0.09 % Low Power: 7 mA typ. Surface-Mount Package 5 VDC Operation Applications Wireless microphone systems Wireless in-ear monitors Compressors and Limiters Gates De-essers Duckers

Basic Specifications (typical) VCA Section Control Constant: ±6.1 mV/dB (both positive and negative-sense control available) Gain Range: < -100 dB to > +30 dB Dynamic Range: > 105 dB THD: < 0.09% Detector Section True RMS response Crest Factor: 10 (for 1 dB reading error) Output Scaling: +6.1 mV/dB Dynamic Range: > 80 dB Bandwidth: > 20 kHz Opamps Input Offset Voltage: ± 0.5 mV Gain-Bandwidth Product: 5 MHz Slew Rate: 2 V/µs Input Voltage Noise:   OA1:  6.5 nV/ÖHz   OA2 & 3:  7.5 nV/ÖHz Overall Supply voltage: 0 - 5 VDC thru 0 - 15 VDC Supply current: typically 7 mA

For complete specifications, download a copy of the 4311 Datasheet. Datasheets are provided in Adobe's PDF format. You need to have Adobe Acrobat Reader installed on your computer to view the file. To obtain a free copy of Acrobat Reader follow the link at right.

Model	Package	Order Number	Pricing (2000)	Min Order Quantity	Reference
4311	20 Pin SMT	4311S	$4.35	50 (Tube)	Datasheet App Notes RoHS Info
4311 RoHS	20 Pin SMT on Tape and Reel	4311S20-IR	$4.42	2000 (Reel)

Minimum Order Quantity (MOQ) is one reel full (4311 RoHS) or one tube full (4311 Leaded). Parts must be ordered in multiples of the MOQ.

Please contact our sales department for pricing and delivery. Pricing is subject to change.

IMPORTANT:
The 4311 is not recommended for new designs
for your new circuits designs see our 4320 Low-Power Analog Engine ICs.