www.ti.com
FEATURES
APPLICATION
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
AGC IN1
AGC IN2
VAGC
GND
LO IN1
LO IN 2
VCC1
VCC2
MIXOUT1
MIXOUT2
GND
IF IN1
IF IN 2
GND
IFOUT1
IFOUT2
16-PIN TSSOP
(TOP VIEW)
DESCRIPTION
FUNCTIONAL BLOCK DIAGRAM
1
2
3
4
5
7
6
8
16
15
14
13
12
10
11
9
Mixer
Buffer
AGC IN1
AGC IN2
VAGC
GND
LO IN1
LO IN2
VCC 1
VCC2
MIXOUT1
MIXOUT2
IF IN1
GND
IFOUT 2
IF IN2
GND
IFOUT 1
IF Amplifier
AGC Amplifier
SN761688DOWN CONVERTER
SLES178 – APRIL 2006
•RF AGC Amplifier, Mixer, and IF AmplifierCircuits
•Low Distortion
•5-V Power Supply•16-Pin TSSOP Package
•CATV
The SN761688 is a monolithic IC designed as an out-of-band tuner for CATV. The circuit consists of an RF AGCamplifier, mixer, and IF amplifier, and is available in a small-outline package.
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled withappropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may bemore susceptible to damage because very small parametric changes could cause the device not to meet its publishedspecifications.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of TexasInstruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright © 2006, Texas Instruments IncorporatedProducts conform to specifications per the terms of the TexasInstruments standard warranty. Production processing does notnecessarily include testing of all parameters.
www.ti.com
3
100 k
30 k
12
1 k1 k
56
3 k3 k
10
9
15 Ω
16
15
16 Ω
12 13
1 k1 k
SN761688
DOWN CONVERTER
SLES178 – APRIL 2006
TERMINAL FUNCTIONS
TERMINAL
DESCRIPTION SCHEMATICNAME NO.
AGC IN1 1 Input of AGC amplifier Figure 1AGC IN2 2VAGC 3 Input of gain control voltage Figure 2GND 4, 11, 14 GroundLO IN1 5 Input of local OSC Figure 3LO IN2 6VCC1 7 5 V power supply; AGC/Mixer/BufferVCC2 8 5 V power supply; IF amplifierIF OUT1 9 Output of IF amplifier Figure 4IF OUT2 10IF IN2 12 Input of IF amplifier Figure 5IF IN1 13MIXOUT2 15 Output of Mixer Figure 6MIXOUT1 16
Figure 1. Figure 2.
Figure 3. Figure 4.
Figure 5. Figure 6.
2
Submit Documentation Feedback
www.ti.com
ABSOLUTE MAXIMUM RATINGS
RECOMMENDED OPERATING CONDITIONS
DC ELECTRICAL CHARACTERISTICS
AC ELECTRICAL CHARACTERISTICS
SN761688DOWN CONVERTER
SLES178 – APRIL 2006
over operating free-air temperature range (unless otherwise noted)
(1)
Supply voltage, V
CC
(2)
VCC1,2 (Pin 7, 8) –0.4 V to 6.5 VInput voltage
(2)
V
IN
(Pins 1, 2, 3, 5, 6, 12, 13) –0.4 V to VCCContinuous total dissipation, P
D
(3)
T
A
≤25°C 775 mWMaximum junction temperature, T
J
150°C
(1) Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratingsonly, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operatingconditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.(2) Voltage values are with respect to the GND of the circuit.(3) Derating factor is 6.2 mW/ °C for T
A
≥25°C.
over operating free-air temperature range (unless otherwise noted)
MIN NOM MAX UNIT
Supply voltage, V
CC
4.5 5 5.5 VOperating free-air temperature, T
A
–20 85 °C
V
CC
= 5 V, T
A
= 25°C, unless otherwise noted
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
I
CC
Supply current No signal, V
AGC
= 0 V 67 mAI
IAGC
Input current (VAGC) V
AGC
= 3 V 22 33 µAV
AGCMAX
AGC voltage high at maximum gain 3 V
CC
VV
AGCMIN
AGC voltage low at minimum gain 0 0.5 V
V
CC
= 5 V, T
A
= 25°C, unless otherwise noted
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
AGC amplifier and mixer
(1)
GC
MAX
Maximum conversion gain V
AGC
= 3 V 27 30 33 dBGC
MIN
Minimum conversion gain V
AGC
= 0 V -21 -18 -15 dBGCR
MIX
Gain control range V
AGC
= 0 V to 3 V 48 dBV
MIXOUT
Mixer output voltage V
AGC
= 3 V, Single-ended output 117 dB µVNF Noise figure
(2)
V
AGC
= 3 V 10 dBThird order intermodulation f
IN1
= 79.5 MHz, f
IN2
= 80.5 MHz,IM3
GMX
-60 dBcdistortion V
OUT
= -10 dBm, V
AGC
= 3 Vf
IN1
= 79.5 MHz, f
IN2
= 80.5 MHz, V
AGCOIP3
GMX
Output intercept point 20 dBm= 3 VIF amplifier
(3)
GV
IFMAX
Maximum voltage gain V
AGC
= 3 V 51 dBGV
IFMIN
Minimum voltage gain V
AGC
= 0 V 46 dBGVR
IF
Gain control range V
AGC
= 0 V to 3 V 5 dBThird order intermodulation f
IN1
= 43.5 MHz, f
IN2
= 445 MHz,IM3
IF
-60 dBcdistortion V
IFOUT
= 1 dBm, V
AGC
= 3 VV
IFOUT
IF amplifier output voltage V
AGC
= 3 V, Single-ended output 122 dB µV
(1) Measurement Circuit 1 except for Noise Figure measurement. AGC IN = 80 MHz/-37 dBm, LO IN = 36 MHz / -20 dBm, IF = 44 MHz,unless otherwise noted.(2) Measurement Circuit 2.(3) Measurement Circuit 3. IF IN = 44 MHz / -50 dBm, unless otherwise noted.
3Submit Documentation Feedback
www.ti.com
APPLICATION INFORMATION
MEASUREMENT CIRCUITS
SN761688
DOWN CONVERTER
SLES178 – APRIL 2006
Figure 7. Measurement Circuit 1
Figure 8. Measurement Circuit 2
4
Submit Documentation Feedback
www.ti.com
SN761688DOWN CONVERTER
SLES178 – APRIL 2006
APPLICATION INFORMATION (continued)
Figure 9. Measurement Circuit 3
NOTE:
This application information is advisory and a performance check is required at theactual application circuits.
Texas Instruments assumes no responsibility for the consequences of use of theseapplication circuits, such as infringement of intellectual property rights or other rights,including patents, of third parties.
5Submit Documentation Feedback
www.ti.com
TYPICAL CHARACTERISTICS
−30
−20
−10
0
10
20
30
40
0.0 0.5 1.0 1.5 2.0 2.5 3.0
AGC control voltage [V]
Gain [dB]
VCC = 4.5 V
VCC = 5 V
VCC = 5.5 V
TA = 25C
−30
−20
−10
0
10
20
30
40
0.0 0.5 1.0 1.5 2.0 2.5 3.0
AGC control voltage [V]
Gain [dB]
TA = −20C
TA = 25C
TA = 85C
VCC = 5 V
60
70
80
90
100
110
120
130
−80 −70 −60 −50 −40 −30 −20 −10 0 10 20
AGC IN Input Level [dBm]
MIXOUT Output Level [dBuV]
VCC = 4.5 V VCC = 5 V
VCC = 5.5 V
TA = 25C,
VAGC = 3 V
60
70
80
90
100
110
120
−80 −70 −60 −50 −40 −30 −20 −10 0 10 20
LO IN Input Level [dBm]
MIXOUT Output Level [dBuV]
TA = −20C
TA = 25C
TA = 85C
VCC = 5 V,
VAGC = 3 V
SN761688
DOWN CONVERTER
SLES178 – APRIL 2006
Mixer Conversion Gain Mixer Conversion Gainvs vsAGC Control Voltage AGC Control Voltage
Figure 10. Figure 11.
Mixer Output Level Mixer Output Levelvs vsAGC IN lnput Level LO IN lnput Level
Figure 12. Figure 13.
6
Submit Documentation Feedback
www.ti.com
5
10
15
20
25
30
35
40
0 10 20 30 40 50
Gain [dB]
NF [dB]
VCC = 5 V,
TA = 25C
−120
−100
−80
−60
−40
−20
0
20
40
−70 −60 −50 −40 −30 −20 −10 0
AGC IN Input Level [dBm]
MIXOUT Output Level [dBm]
43.5 MHz
42.5 MHz
AGC IN = 79.5 MHz / 80.5 MHz,
LO IN = 36 MHz
VCC = 5 V, TA = 25C
−30
−20
−10
0
10
20
30
40
0 100 200 300 400 500 600
AGC IN Input Freq [MHz]
MIXER GAIN [dB]
VAGC = 3 V
VAGC = 0 V
VCC = 5 V,
TA = 25C
40
45
50
55
0.0 0.5 1.0 1.5 2.0 2.5 3.0
AGC control voltage [V]
Gain [dB]
VCC = 4.5 V
VCC = 5 V
VCC = 5.5 V
VCC = 5 V,
TA = 25C
SN761688DOWN CONVERTER
SLES178 – APRIL 2006
TYPICAL CHARACTERISTICS (continued)
Mixer NFvs Mixer IM3 (VAGC = 3 V)Gain
Figure 14. Figure 15.
IF Amp GainMixer Frequency Response vsAGC Control Voltage
Figure 16. Figure 17.
7Submit Documentation Feedback
www.ti.com
−100
−80
−60
−40
−20
0
20
40
−80.0 −70.0 −60.0 −50.0 −40.0 −30.0 −20.0 −10.0
IF IN input level [dBm]
IFOUT output level [dBm]
43.5 MHz
42.5 MHz
VCC = 5 V,
TA = 25C
IF IN = 43.5 MHz / 44.5 MHz
40
45
50
55
0.0 0.5 1.0 1.5 2.0 2.5 3.0
AGC control voltage [V]
Gain [dB]
TA = −20C
TA = 25C
TA = 85C
VCC = 5 V
8.0
9.0
10.0
11.0
12.0
40.0 45.0 50.0 55.0 60.0
IFAMP Gain [dB]
NF [dB]
VCC = 5 V,
TA = 25C
SN761688
DOWN CONVERTER
SLES178 – APRIL 2006
TYPICAL CHARACTERISTICS (continued)
IF Amp Gain
vs IF Amp IM3 (AGC = 3 V)AGC Control Voltage
Figure 18. Figure 19.
IF Amp NFvs
Gain
Figure 20.
8
Submit Documentation Feedback
www.ti.com
S-PARAMETER
SN761688DOWN CONVERTER
SLES178 – APRIL 2006
TYPICAL CHARACTERISTICS (continued)
Figure 21. AGC IN
Figure 22. IF IN
9Submit Documentation Feedback
www.ti.com
SN761688
DOWN CONVERTER
SLES178 – APRIL 2006
TYPICAL CHARACTERISTICS (continued)
Figure 23. IF OUT
10
Submit Documentation Feedback
PACKAGE OPTION ADDENDUM
www.ti.com 31-Mar-2012
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status (1) Package Type Package
Drawing Pins Package Qty Eco Plan (2) Lead/
Ball Finish MSL Peak Temp (3) Samples
(Requires Login)
SN761688PW OBSOLETE TSSOP PW 16 TBD Call TI Call TI
SN761688PWR NRND TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
SN761688PWRG4 NRND TSSOP PW 16 2000 Green (RoHS
& no Sb/Br) CU NIPDAU Level-1-260C-UNLIM
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
SN761688PWR TSSOP PW 16 2000 330.0 12.4 6.9 5.6 1.6 8.0 12.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 14-Jul-2012
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
SN761688PWR TSSOP PW 16 2000 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 14-Jul-2012
Pack Materials-Page 2
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46C and to discontinue any product or service per JESD48B. Buyers should
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All
semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale supplied at the time
of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components which meet ISO/TS16949 requirements, mainly for automotive use. Components which
have not been so designated are neither designed nor intended for automotive use; and TI will not be responsible for any failure of such
components to meet such requirements.
Products Applications
Audio www.ti.com/audio Automotive and Transportation www.ti.com/automotive
Amplifiers amplifier.ti.com Communications and Telecom www.ti.com/communications
Data Converters dataconverter.ti.com Computers and Peripherals www.ti.com/computers
DLP® Products www.dlp.com Consumer Electronics www.ti.com/consumer-apps
DSP dsp.ti.com Energy and Lighting www.ti.com/energy
Clocks and Timers www.ti.com/clocks Industrial www.ti.com/industrial
Interface interface.ti.com Medical www.ti.com/medical
Logic logic.ti.com Security www.ti.com/security
Power Mgmt power.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense
Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video
RFID www.ti-rfid.com
OMAP Mobile Processors www.ti.com/omap TI E2E Community e2e.ti.com
Wireless Connectivity www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2012, Texas Instruments Incorporated