1606Q16-U - THAT - Product.Network

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

Tel: +1 (508) 478-9200; Fax: +1 (508) 478-0990; Web: www.thatcorp.com

THAT 1606, 1646

Description

The THAT 1606 and 1646 are a new generation

of monolithic audio differential line drivers offering

improved performance over conventional cross-cou-

pled designs. Based on a high-performance, fully dif-

ferential opamp and laser-trimmed thin-film

resistors, both families exhibit low noise and distor-

tion, high slew rate, and wide output swing. The

parts are stable when driving difficult loads, and

have short-circuit protected outputs.

Designed from the ground up in THAT's comple-

mentary dielectric isolation process, both models in-

corporate THAT's patented OutSmarts1technology.

This is a dual feedback-loop design that prevents the

excessive ground currents typical of cross-coupled

output stages (CCOS) when clipping into sin-

gle-ended loads. OutSmarts uses two individual neg-

ative-feedback loops to separately control the

differential output voltage and common mode output

currents, making the designs inherently more stable

and less sensitive to component tolerances than

common CCOSes. As a result, THAT's topology pre-

vents the loss of common-mode feedback that

plagues common CCOS designs when clipping into

single-ended loads. This avoids excessive ground

currents that would otherwise upset power supplies

and create additional distortion, even in adjacent

channels.

The 1646 is pin-compatible with the TI DRV134

and DRV135, as well as the Analog Devices

SSM2142. The 1606 offers an advanced com-

mon-mode offset voltage reduction scheme, which re-

quires a small single capacitor instead of the two

electrolytics required by the 1646 and its

pin-compatible cousins. Additionally, the 1606 fea-

tures differential inputs in a space-saving 16-pin

QSOP package. Both parts offer +6 dB gain.

THAT Corporation Balanced Line Driver ICs

FEATURES

•Balanced, transformer-like floating

output

•OutSmarts®technology improves

clipping into single-ended loads

•Stable driving long cables and

capacitive loads

•High output: 18Vrms into 600 W

•Low noise: -101 dBu

•Low distortion: 0.0007% @ 1kHz

•Industry-standard pinout

APPLICATIONS

•Differential Line Drivers

•Audio Mixing Consoles

•Distribution Amplifiers

•Hi-Fi Equipment

•Audio Equalizers

•Dynamic Range Processors

•Digital Effects Processors

•Telecommunications Systems

•Instrumentation

Din+

Cin+

Cin-

Din-

Out-

Sns-

Out+

Sns+

Vcc

In+

Vee

Gnd

Dout-

Dout+

10k

20k

10p

THAT 1646

CEXT

Figure 1. THAT 1646 Equivalent Circuit Diagram

1646 1606

Pin DIP8 SO8 SO16W QSOP16

1 Out- Out- NC Gnd*

2 Sns- Sns- NC NC

3 Gnd Gnd Out- Out-

4In

In Sns- Cap1

5Vee

Vee Gnd Gnd

6 Vcc Vcc In In-

7 Sns+ Sns+ NC In+

8 Out+ Out+ NC Gnd*

9 — — NC Gnd*

10 — — NC NC

11 — — Vee Vee

12 — — Vcc Vcc

13 — — Sns+ Cap2

14 — — Out+ Out+

15 — — NC NC

16 — — NC Gnd*

* See “Thermal Considerations” section on page 10

Table 1. THAT 1606/1646 pin assignments

1. For complete details of OutSmarts, see Hebert, Gary K., "An Improved Balanced, Floating Output Driver IC", presented at the 108th AES Convention, February 2000.

Protected under US Patents numbers 4,979,218 and 6,316,970. Additional patents pending. THAT and OutSmarts are registered trademarks of THAT Corporation.

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

Tel: +1 (508) 478-9200; Fax: +1 (508) 478-0990; Web: www.thatcorp.com

Document 600078 Rev 05 Page 2 of 12 THAT1606/1646 Balanced Line Driver ICs

Absolute Maximum Ratings (TA= 25°C)

Positive Supply Voltage (Vcc) +20 V Storage Temperature (TST) -55 to +125°C

Negative Supply Voltage (Vee) -20 V Junction Temperature (TJ) 125°C

Output Short Circuit Duration Continuous Lead Temperature (TLEAD)(Soldering 60 sec) 300°C

Operating Temperature Range (TOP) -40 to +85°C

SPECIFICATIONS2

2. All specifications are subject to change without notice.

3. Unless otherwise noted,.all measurements taken with VS=±18V, T=25°C, RL= 600 WBalanced, RSOURCE =0W

1646 Electrical Characteristics3

Parameter Symbol Conditions Min. Typ. Max. Units

Input Impedance ZIN 4.00 5.00 kW

Gain G1 RL=100 kWper output

Balanced 5.80 6.00 6.20 dB

Single Ended 5.76 5.96 6.16 dB

Gain G2 RL= 600 W

Balanced 5.00 5.30 5.60 dB

Single Ended 4.96 5.26 5.56 dB

Gain Error G1 RL=100 kWper output, Balanced 0.02 0.20 dB

DC Power Supply

Rejection Ratio PSRR ±4V to ±18V 85 107 dB

Output Common-Mode

Rejection Ratio CMRROUT f=1kHz, BBC Method 46 65 dB

Output Signal Balance Ratio SBR f=1kHz, BBC Method 35 54 dB

THD+N (Balanced) THD+N1VO=10 VRMS,R

L=600 W

20Hz-5kHz 0.0007 %

20kHz 0.002 0.005 %

THD+N (Single Ended) THD+N2VO=10 VRMS,R

L=600 W

20Hz-5kHz 0.0010 %

20kHz 0.0030 0.0060 %

Output Noise Onoise Balanced, 22Hz -20kHz -101 dBu

Maximum Output Level VoMAX 0.1% THD+N 27.5 dBu

Slew Rate SR CL=50pF/output 15 V/µS

Small Signal Bandwidth CL=50pF/output 10 MHz

Output Common Mode

Voltage Offset VOCM1 w/o Sense capacitors -250 ±50 250 mV

VOCM2 w/ Sense capacitors -15 ±3.5 15 mV

Differential Output Offset VOD -15 ±4 15 mV

Output Voltage Swing, Positive No Load VCC–2.9 VCC–2.2 V

Output Voltage Swing, Negative No Load VEE+2.25 VEE+2.9 V

Output Impedance ZO40 50 60 W

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

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THAT1606/1646 Balanced Line Driver ICs Page 3 of 12 Document 600078 Rev 05

Maximum Capacitive Load Stable Operation Unlimited µF

Quiescent Supply Current ISUnloaded 4.9 5.75 mA

Output Short Circuit Current ISC Both outputs to ground 70 mA

Power Supply Voltage Range ±4 ±18 V

1646 Electrical Characteristics (cont’d)

Parameter Symbol Conditions Min. Typ. Max. Units

1606 Electrical Characteristics3

Parameter Symbol Conditions Min. Typ. Max. Units

Input Impedance ZIN 4.00 5.00 kW

Gain G1 RL=100 kW/ output

Balanced 5.80 6.00 6.20 dB

Single Ended 5.76 5.96 6.16 dB

Gain G2 RL= 600 W

Balanced 5.00 5.30 5.60 dB

Single Ended 4.96 5.26 5.56 dB

Gain Error G1 RL=100 kW/ output, Balanced 0.02 0.20 dB

DC Power Supply

Rejection Ratio PSRR ±4V to ±18V 85 107 dB

Output Common-Mode

Rejection Ratio CMRROUT f=1kHz, BBC Method 46 65 dB

Input Common-Mode

Rejection Ratio CMRRIN f=1kHz 40 60 dB

Output Signal Balance Ratio SBR f=1kHz, BBC Method 35 54 dB

THD+N (Balanced) THD+N1VO=10 VRMS,R

L=600 W

20Hz-5kHz 0.0007 %

20kHz 0.002 0.005 %

THD+N (Single Ended) THD+N2VO=10 VRMS,R

L=600 W

20Hz-5kHz 0.0010 %

20kHz 0.0060 0.0075 %

Output Noise Onoise Balanced, 22Hz -20kHz -101 dBu

Maximum Output Level VoMAX 0.1% THD+N 27.5 dBu

Slew Rate SR CL=50pF/output 15 V/µS

Small Signal Bandwidth CL=50pF/output 10 MHz

Common Mode Output

Voltage Offset VOCM1 w/o CM coupling capacitor -250 ±50 250 mV

VOCM2 w/ CM coupling capacitor -20 -5 20 mV

Differential Output Offset VOD -15 ±4 15 mV

Output Voltage Swing, Positive No Load VCC–2.9 VCC–2.2 V

Output Voltage Swing, Negative No Load VEE+2.25 VEE+2.9 V

Output Impedance ZO40 50 60 W

Maximum Capacitive Load Stable Operation Unlimited µF

Quiescent Supply Current ISUnloaded 4.9 5.75 mA

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

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Document 600078 Rev 05 Page 4 of 12 THAT1606/1646 Balanced Line Driver ICs

Out-

Cap1Cap2

Out+

Vcc

In+

Vee

In-

10k

10p

THAT 1606

CEXT

REXT

Din+

Cin+

Cin-

Din-

Dout-

Dout+

Gnd

Figure 3. THAT 1606 Equivalent Circuit Diagram

Din+

Cin+

Cin-

Din-

Out-

Sns-

Out+

Sns+

Vcc

In+

Vee

Gnd

Dout-

Dout+

10k

20k

10p

THAT 1646

CEXT

Figure 2. THAT 1646 Equivalent Circuit Diagram

Output Short Circuit Current ISC Both outputs to ground 70 mA

Power Supply Voltage Range ±4 ±18 V

1606 Electrical Characteristics (cont’d)

Parameter Symbol Conditions Min. Typ. Max. Units

Theory of Operation

OutSmarts®technology

The THAT 1606 and 1646 family employs the

OutSmarts topology, a variation of circuitry originally

developed by Chris Strahm at Audio Teknology Inc.,

(and later acquired by Audio Toys, Inc.). THAT's

OutSmarts topology employs two negative-feedback

loops -- one to control the differential signal, and a

separate loop to control the common mode output

levels.

Figures 2 and 3 show the gain core common to

the 1606 and 1646. The gain core is a single ampli-

fier that includes two differential input pairs, Cin+/-

and Din+/-, and complementary outputs, Vout+ and

Vout-, related to each other by two gain expressions,

AD(s) and AC(s). The first pair of differential inputs,

Din+/-, is connected to the differential feedback net-

work between the outputs and the input signal. The

second differential input pair, Cin+/-, is connected to

a bridge circuit which generates an error signal used

to servo the common-mode behavior of the outputs.

The loop equations are then:

()

DD DADD

OUT OUT OUT D IN IN+- +-

-= = -D,

where AD is the differential open-loop gain, and

()

DD DACC

OUT OUT OUT C IN IN+- +-

+= = -S,

where AC is the common-mode open-loop gain.

These equations can be solved much like stan-

dard op-amp loop equations.

For the differential case, using superposition, we

can see that this results in:

DD In

IN OUT+-+

1323, and

DD In

IN OUT-+

=+-

1323.

Substituting and simplifying into the equation

that defines differential operation yields:

[]

D A In In

OUT D

DOUT

=+-

3()

Dividing through by AD(assuming that AD>> 3) and

simplifying yields

()

DDInIn

OUT =-

as one would expect for a +6 dB line driver.

For the 1646, In- is hard-wired to ground (0v), so

the differential equation above simplifies to:

()

DDIn

OUT =+

The common mode equation is more complicated

in that it is dependent on the attached load, and in

any event doesn't yield much insight into the device's

operation. For those who are interested, a more

complete discussion is given in the reference men-

tioned in note 1.

In op-amp analysis using negative feedback loops,

the combination of negative feedback and high

open-loop gain usually results in the open-loop gain

"dropping out" of the equation, and the differential in-

puts being forced to the same potential. This is true

for the core of the 1606 and 1646 ICs. If we start

with that assumption, the operation of the com-

mon-mode feedback loop can be intuited as follows:

Referring again to Figures 2 and 3, the common-

mode input actually senses the sum of each IC's out-

put currents by way of two 25 Wresistors and the

bridge network4. The resulting error signal is ampli-

fied and then summed into both outputs, with the net

effect being to force the sum of the currents to be

zero, and thus the common mode output current to

zero.

To see why this is important, consider what hap-

pens when the IC is loaded with a single-ended load,

which shorts one or the other output to ground.

Suppose Out- is grounded. In this case, the differen-

tial feedback loop increases the voltage at Dout+ to

make up for most of the signal lost to the short at

Out-. The common-mode feedback loop forces the

current from Out- to be equal and opposite to that

from Out+. But, during peak signals which drive

Dout+ into clipping (exceeding its maximum output

voltage capability), the differential loop is starved for

feedback. Without the common-mode feedback, the

result would be for the voltage at Dout- to decrease in

an attempt to satisfy the differential loop's demand

for feedback. This is one significant weakness of

conventional cross-coupled output designs – com-

mon-mode feedback is lost when one output is

clipped while the other is grounded.

With OutSmarts, however, the common mode

feedback loop senses this happening because of the

increase in current at Out- (compared to that at

Out+), and prevents the voltage at Out- from rising

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

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THAT1606/1646 Balanced Line Driver ICs Page 5 of 12 Document 600078 Rev 05

4. The 10 pF capacitor can be ignored for the purposes of this analysis. It simply limits the maximum frequency at which the current-sensing action occurs

out of control. This causes the OutSmarts design to

more closely mimic the behavior of a true floating

balanced source (such as a transformer), compared

to the behavior of a conventional CCOS design.

Applications

1. Circuit implementations using the 1606 and

1646 are relatively straightforward. A quiet, solid

ground reference, stiff voltage supplies, and adequate

supply bypassing are all that are required to achieve

excellent performance out of both ICs.

2. Both devices must be driven from a

low-impedance source, preferably directly from

opamp outputs, to maintain the specified perfor-

mance.

3. Please refer to Figure 8 for a complete applica-

tions circuit.

Stability and Load Capacitance

The devices are stable into any capacitive load,

and the maximum capacitance is limited only by slew

rate and frequency response considerations.

For the purposes of the frequency response calcu-

lation, the line driver's 25Wsense resistors can be

lumped into a single 50Wresistor. The correct cable

capacitance to use for the balanced-signal case is the

sum of the inter-conductor capacitance and the two

conductor-to-shield capacitances in series. Some

manufacturers only specify the inter-conductor ca-

pacitance and the capacitance of one conductor to

the other while connected to the shield, and some ex-

traction may be required.

As an example, Belden 8451 is specified as hav-

ing with 34 pF/ft of inter-conductor capacitance and

67 pF/ft of conductor to "other conductor + shield

capacitance". Thus, we can assume a single conduc-

tor-to-shield capacitance of 33 pF/ft (the difference

between 67 and 34) for each conductor. For balanced

signals, the load capacitance across the 1646 outputs

will be 34 pF/ft + 16.5 pF/ft = 50.5 pF/ft. The corner

frequency of the THAT 1646 driving 500 ft of this ca-

ble (25.25 nF) will be 126 kHz.

fkHz

CpF

×× × +

2 50 500 34 16 5 126

pW (.)

One must also consider the slew rate limitations

posed by excessive cable and other capacitances. We

know that

and that

dt Peak

Vf=××2p

Dennis Bohn of Rane Corporation has published

work specifying some of the requirements for a bal-

anced line driver, including a) stability into reactive

loads, b) differential output voltage swing of at least

±11 volts peak (+20dBu), and c) reliability5. This

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

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Document 600078 Rev 05 Page 6 of 12 THAT1606/1646 Balanced Line Driver ICs

Gnd

Out-

Out+

THAT1646

Vcc

Vee

100n

Vcc

Sns+

Vee

Sns-

Out+

Out-

Figure 4. THAT 1646 without common-mode offset reduction

5. Dennis A. Bohn, “Practical Line-Driving Current Requirements“(Rane Note 126), Rane Corporation, 1991, revised 5/1996. Available at www.rane.com/note126.html.

work suggests a reasonable rule by which to calculate

the output current requirements at 20kHz. The au-

thor concludes that the actual worst case peak level

for various types of music and speech will be flat out

to 5kHz, and roll off at 6dB/octave above this fre-

quency. Thus the peak levels at 20kHz will be 12dB

below those at 5kHz.

Using these, we can calculate the required slew

rate and current drive. For the +26 dBu output lev-

els that the 1646 is capable of, VPeak is 22V (below

5kHz), and at 20kHz, VPeak is 5.5V. Therefore,

VkHz=× × =255 20 069pm

As a consequence,

ift mA

=× + × =500 34 16 5 0 69 17 5(.)..

Thus, driving this 25.25 nF cable requires 17.5

mAPeak, which is well within the capability of the

1606 and 1646.

Gain structure

The 1606 and 1646 both provide +6 dB gain (fac-

tor of 2) between their inputs and differential out-

puts. This is appropriate, since with a balanced

output, twice the voltage between the power supply

rails is available at the output of the stage. The sin-

gle-ended input of the 1646 can accept signals that

swing to nearly the power supply rails without distor-

tion, when driving into a differential (floating) load.

The balanced input of the 1606 can accept signals at

each input that swing to nearly one-half the power

supply rails without distortion, when driving into dif-

ferential loads.

Both devices, when driving single-ended loads,

will clip at about half the output voltage as compared

to a differential load. This is because only one of the

two output signals will be available. Despite the out-

put clipping, the input to the devices does not need to

be constrained - they will work without undue prob-

lems being overdriven at their inputs when the out-

puts are clipping into single-ended loads.

1646 circuits

Figure 4 shows the most basic connection for a

1646. The only external components needed are the

local 100nF bypass capacitors. These should be

within 1 inch of the 1646 pins.

Output DC offset

Because the 1646's outputs are connected directly

to their respective sense inputs, this circuit may pro-

duce up to 250mV of common-mode dc offset at its

outputs. As shown, the outputs are DC coupled to

the output connector, so this dc will appear directly

at the output of the system.

The output common-mode offset of a 1646 may

be reduced by adding capacitors in the feedback

loop, as shown in Figure 5. Capacitors C1 and C2

ac-couple the common-mode feedback loop. This

changes the loop operation from servoing the com-

mon-mode output current at audio frequencies to

servoing the common-mode output voltage to 0 at

DC. This results in much lower common-mode out-

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

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THAT1606/1646 Balanced Line Driver ICs Page 7 of 12 Document 600078 Rev 05

Gnd

Out-

Out+

THAT1646

Vcc

Vee

100n

Vcc

Sns+

Vee

Sns-

10u

Out+

Out-

Figure 5. THAT 1646 with common-mode offset reduction

put offset voltage, as indicated in the specifications

section. C1 and C2 are typically high quality

non-polarized electrolytic capacitors.

1606 circuits

Figures 6 and 7 show the basic amplifier configu-

rations for a 1606. The 1606 differs from the 1646

in two respects. First, the 1606 includes a nega-

tive-sense input pin (pin 6), so offers a differential in-

put. This can be useful in connecting the output

driver to the output of modern D/A converters, which

usually present differential outputs. Second, instead

of two 10uF capacitors, the 1606 uses an 0.1uf ca-

pacitor (C1) and 1MW(R1) resistor to reduce com-

mon-mode dc offset. Generally, these components

will cost less, and take up less space on the circuit

board than the two large capacitors required for the

1646. C1 should be a high-quality film type capaci-

tor to minimize low-frequency distortion when driv-

ing single-ended loads.

RFI protection

These line drivers can easily drive cables hun-

dreds of feet in length without becoming unstable,

but such long cables can act as antennae which can

pick up RFI and direct it into the circuit. The circuit

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Document 600078 Rev 05 Page 8 of 12 THAT1606/1646 Balanced Line Driver ICs

In+

Gnd

Out-

Out+

THAT1606

Vcc

Vee

100n

Vcc

Cap1

Vee

Cap2

100n

In-

1M0

Out+

Out-

Figure 6. THAT 1606 with output common-mode offset reduction and single-ended input drive

In+

Gnd

Out-

Out+

THAT1606

In+

Vcc

Vee

100n

Vcc

Cap1

Vee

Cap2

100n

In-

1M0

In-

Out+

Out-

Figure 7. THAT 1606 with output common-mode offset reduction and differential input drive

of Figure 8 includes two 100 pF bypass capacitors

C3 and C8 and two ferrite beads, whose purpose is

to redirect this RF energy to the chassis before it can

circulate inside the product's box and couple RF into

other portions of the circuit. The capacitors should

be located as close as possible to the output connec-

tor and connected via a low-inductance path to chas-

sis ground, with the ferrite beads placed very nearby.

These components ensure that RFI current is di-

rected to the chassis and not through the relatively

low-impedance output of the 1606/1646. The bypass

capacitors and ferrite beads will have no effect on the

gain error of these line drivers at audio frequencies.

Output protection

The 1606 and 1646 each incorporate a propri-

etary internal protection scheme, which will suffice

for many situations seen in the field. However, one

might foresee having the line driver's output mistak-

enly plugged directly into a microphone preamplifier

input that has +48V phantom power applied. When

this happens, the ac coupling capacitors on the

preamp's input will discharge into the low-impedance

output of the 1606/1646. This can result in surge

currents of over 2 amperes6. The amount of energy

stored in these capacitors is directly proportional to

the capacitor value, which is, of course, not under the

1606/1646 designer's control. The 1606/1646's in-

ternal protection network will withstand this abuse

for coupling capacitors up to about 33 uF.

To protect against microphone preamplifiers that

incorporate larger values of capacitance, a pair

1N4004 diodes from each output to the supply rails,

as shown in Figure 8, is recommended. This shunts

the discharge current to the power supply bypass

and filter capacitors, thus protecting the output of

the 1606 or 1646.

Closing thoughts

The integrated balanced line driver is one of those

highly useful, cost-effective functional blocks that can

provide significant improvement over discrete de-

signs. The THAT 1646 goes a step or two further by

improving over existing components. Both incorpo-

rate OutSmarts technology to tame the aberrant sin-

gle-ended clipping behavior of conventional

cross-coupled output stages.

For more information on these or other THAT

Corporation integrated circuits, please contact us di-

rectly, or through one of our international distribu-

tors.

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

Tel: +1 (508) 478-9200; Fax: +1 (508) 478-0990; Web: www.thatcorp.com

THAT1606/1646 Balanced Line Driver ICs Page 9 of 12 Document 600078 Rev 05

Input

Gnd

Input

1N4004

100p

Ferrite Bead

Out-

Out+

Vcc

Vee

Vcc

Vee

Amplifier

Block

(from fig.

5, 6, or 7)

XLR (M)

Figure 8. THAT 16x6 applications circuit with output common-mode offset protection, RFI protection, and surge protection

6. Hebert, Gary K., Thomas, Frank W., "The 48V Phantom Menace", presented at the 110th Audio Engineering Society Convention, May, 2001

Package Information

The THAT1646 in available in 8-pin SO, 8-pin

mini-DIP and 16-pin wide SOIC packages. The 1606

comes in a 16-pin QSOP package Package dimen-

sions are shown in Figures 9, 10, 11, and 12, while

pinouts are given in Table 1.

Thermal Considerations

As mentioned. the 1646 is available in an 8-pin

DIP, and 16-pin wide SO, and an 8-pin SO, with junc-

tion-to-ambient thermal resistances of 100°C/watt,

80°C/watt, and 150°C/watt, respectively, assuming a

2-sided PCB with no ground planes. Users of the

SO-8 package should recognize driving 600 Wloads

or very long cables (several hundred feet) at high am-

bient temperatures (above 55°C) continuously could

lead to internal die temperatures that exceed the

maximum rating and result in performance degrada-

tion.

The 1606 is supplied in a 16-pin QSOP package

in which pins 1, 8, 9, and 16 are fused to the die

paddle to assist in conducting heat away from the

die. These pins are connected to the die substrate,

which is, in turn, connected to the ground pin of the

device. When these pins are connected to a top-side

ground plane of 1 square inch area, the junc-

tion-to-ambient thermal resistance is 125°C/watt. In-

ternal planes on multi-layer PCBs will reduce the

thermal resistance further.

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Document 600078 Rev 05 Page 10 of 12 THAT1606/1646 Balanced Line Driver ICs

Model SO8

Pkg

DIP8

Pkg

SO16W

Pkg

QSOP16

Pkg

1646 1646S08-U 1646P08-U 1646W16-U —-

1606 —- —- —- 1606Q16-U

Table 2. Order Number Information

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THAT1606/1646 Balanced Line Driver ICs Page 11 of 12 Document 600078 Rev 05

0-8º

ITEM MILLIMETERS INCHES

A4.80 - 4.98 0.189 - 0.196

B3.81 - 3.99 0.150 - 0.157

C5.79 - 6.20 0.228 - 0.244

D0.20 - 0.30 0.008 - 0.012

E0.635 BSC 0.025 BSC

G1.35 - 1.75 0.0532 - 0.0688

H0.10 - 0.25 0.004 - 0.010

I0.40 - 1.27 0.016 - 0.050

J0.19 - 0.25 0.0075 - 0.0098

Figure 12. 16 pin QSOP package outline drawing

ITEM

MILLIMETERS

10.11/10.31

7.40/7.60

10.11/10.51

0.36/0.46

1.27

2.44/2.64

0.23/0.32

0.51/1.01

0.10/0.30

INCHES

0.398/O.406

0.291/0.299

0.398/0.414

0.014/0.018

0.050

0.096/0.104

0.009/0.013

0.020/0.040

0.004/0.012

Figure 11. 16 pin wide SO package outline drawing

0.41/0.89

0.31/0.71

0.016/0.035

0.012/0.027

0.230/0.244

0.007/0.010

0.060/0.068

0.014/0.018

0.188/0.197

0.004/0.008

INCHES

0.150/0.157

ITEM MILLIMETERS

0.36/0.46

0.18/0.25

1.52/1.73

1.27

4.78/5.00

0.10/0.20

3.81/3.99

5.84/6.20

0.050

0-8°

hx45°

Figure 9. 8 pin SO package outline drawing

ITEM

MILLIMETERS

9.52 0.10

6.35 0.10

7.49/8.13

0.46

2.54

3.68/4.32

0.25

3.18 0.10

8.13/9.40

3.30 0.10

INCHES

0.375

0.250 0.004

0.295/0.320

0.018

0.100

0.145/0.170

0.010

0.125 0.004

0.320/0.370

0.130 0.004

±0.004

Figure 10. 8 pin DIP package outline drawing

Revision History

Revision ECO Date Changes Page

00 — 9/26/2006 Released —

01 — 1/12/2007 - Changed 1606 THD+N specification.

- Changed the XLR orientation in Figures4-9.

- Changed the recommendation for common-mode offset

capacitors to be high quality film type.

6-9

02 — 8/6/2007 Reversed the SNS+ ans SNS- pins in Figures 1 and 2. 1, 4

03 — 9/24/2007 - Changed the Quiescent Supply Current specification.

- Correction to the output pins in figures 4 through 9

2, 3

6-9

04 2323 10/16/2009 Changed Table 1. toinclude all the pin numbers including unused

and ground pins.

05 2526 5/11/2011 Revised Figures4-9andaccompanying text to clarify the

recommended application circuits.

6-10

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

Tel: +1 (508) 478-9200; Fax: +1 (508) 478-0990; Web: www.thatcorp.com

Document 600078 Rev 05 Page 12 of 12 THAT1606/1646 Balanced Line Driver ICs