• High-current differential output driver
• Balanced, transformer-like floating output
• +6.0dB gain, balanced or single-ended termination
• OutSmarts technology tames clipping
into single-ended loads
• Stable driving long cables and capacitive loads
• High output: +28dBu into 600 Ω
• Low noise: -101 dBu
• Low distortion: 0.0007% @ 1kHz
• Industry-standard pinout (1646)
• Differential input (1606)

Datasheet Download

Datasheet Download
1606/1646 Datasheet (275 kB)
OutSmarts® Balanced Line Driver ICs


• Differential Line Drivers
• A/D converter Drivers
• Audio Mixing Consoles
• Distribution Amplifiers
• Hi-Fi Equipment
• Telecommunications Systems
• Instrumentation


The THAT 1606 and 1646 are a new generation of monolithic differential line drivers offering improved performance over conventional cross-coupled designs. Based on a high-performance, fully differential op amp and laser-trimmed thin-film resistors, both families exhibit low noise and distortion, high slew rate, and wide output swing. The parts are stable when driving difficult loads, and have short-circuit protected outputs. Both models incorporate THAT’s patented OutSmarts technology. Outsmarts is a dual feedback-loop design that prevents the excessive ground currents typical of cross-coupled output stages (CCOS) when clipping into single-ended loads.

The 1646 is pin-compatible with the TI DRV134 and DRV135, as well as the Analog Devices SSM2142.

The unique 1606 offers differential inputs, a space-saving connection to minimize output dc offset, and comes in a special 16-pin QSOP which improves power dissipation without sacrificing footprint.

Key Specifications (see 1606/1646 datasheet for complete specifications)
Parameter Conditions 1646 Typical 1606 Typical Units
Maximum Output Level 28 28 dBu
Output Noise -101 -101 dBu
THD+N (Balanced) 20 Hz – 5 kHz
20 kHz
THD+N (Single-ended) 20 Hz – 5 kHz
20 kHz
Gain (G1) 100 kΩ 6.00 6.00 dB
Gain Error 0.02 0.02 dB
Output Impedance 50 50 Ω
Output Common-Mode Rejection Ratio 65 65 dB
Slew Rate 15 15 V/µs
Short-circuit Output Current 70 70 mA
Power Supply Voltage ± 4 ~ ± 18 ± 4 ~ ± 18 V
Power Supply Current 4.9 4.9 mA
Model Package Order Number Pricing (1000) Min Order Quantity Reference
1606 16 pin QSOP 1606Q16-U $3.00 98 Request Samples
16 pin QSOP Tape & Reel 1606Q16-UR Contact us 2000
8 pin DIP
8 pin SOIC 1646S08-U $2.91 98
8 pin SOIC Tape & Reel
Contact us 2000
16 pin SOIC Wide
16 pin SOIC Wide Tape & Reel
Contact us 1000
All 1606/1646 parts are RoHS compliant.

Minimum order quantity (MOQ) is one tube or one reel. Parts must be ordered in multiples of the MOQ. Samples are available to qualified applicants. Pricing is subject to change. ICs designated -UR are available on tape and reel for a modest increase in price and require an extended lead time. Please contact our sales department for pricing and current lead time.

Design Notes (as PDF files)

Analog Secrets Your Mother Never Told You (1528k)
Originally presented at the 123rd AES Convention, this seminar provides tips and techniques to achieve optimal performance in the analog signal path. Topics covered range from inputs (balanced line and mic level) to outputs (balanced to single-ended), and include analog signal processing (VCAs, RMS detection, and Analog Engines).

Related Products
Balanced Line Receivers
THAT 1200 Series Single Channel Balanced Line Receivers 1200 Series Datasheet
THAT 1240 Series Single Channel Balanced Line Receivers 1240 Series Datasheet
THAT 1250 Series Low-Cost Single Channel Balanced Line Receivers 1250 Series Datasheet
THAT 1280 Series Dual Channel Balanced Line Receivers 1280 Series Datasheet
THAT 1290 Series Low-Cost Dual Channel Balanced Line Receivers 1290 Series Datasheet
Audio Preamplifiers
THAT 1510/1512 Low Noise High Performance Audio Preamplifier 1510/1512 Datasheet

Additional Resources

1606/1646 Demo Board
– The THAT 1606/1646 Demonstration System (US$100) allows an engineer to test the performance of a THAT 1606 or 1646 IC quickly and easily. The 1606/1646 Demo Board is self-contained circuit board with XLR connectors for signal input and output and a 3-pin header for connection to an external regulated DC power supply (not included). See the 1606/1646 DEMO Datasheet for more information.

1606 Surface Mount Adapter Board
– For our integrated circuits which are only available in surface mount packages THAT Corporation offers adapter boards which allow one of these surface-mount ICs to interface to a circuit board via traditional thru-hole mounting. These adapters make it easy for a design engineer to evaluate our surface-mount products on a prototype board without having to employ SMT technology. Adapter boards are available to qualified applicants.

Line Driver Comparison Chart
– The 1646 is pin-compatible with the TI DRV134 and DRV135, as well as the Analog Devices SSM2142. Both the 1646 and 1606 offer superior performance. See here a chart of the features and specifications of our OutSmarts line drivers to competing, and in some cases pin-compatible, components.

Line Driver Clipping Behavior
– THAT 1646 and 1606 Line Drivers use a dual feedback-loop design that prevents the excessive ground currents typical of cross-coupled output stages (CCOS) when clipping into single-ended loads. In these clipping performance graphs you can see the superior clipping behavior of OutSmarts technology versus our competitor’s line drivers.

Part Number Cross Reference
– A chart of THAT part numbers cross-referenced to other IC manufacturers.

Harsh Environment Packaging
– TT Semiconductor repackages THAT Corporation’s IC products in ruggidized plastic for the medical, aerospace, defense, and heavy industrial marketplaces.

1606/1646 Material Data Declaration Sheet
Material Data Declaration Sheets (MDDS) disclose the hazardous materials in our integrated circuits as required by the European RoHS directive.