1 MHz to 10 GHz, 55 dB
Log Detector/Controller
AD8317
Rev. B
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FEATURES
Wide bandwidth: 1 MHz to 10 GHz
High accuracy: ±1.0 dB over temperature
55 dB dynamic range up to 8 GHz ± 3 dB error
Stability over temperature: ±0.5 dB
Low noise measurement/controller output, VOUT
Pulse response time: 6 ns/10 ns (fall/rise)
Small footprint, 2 mm × 3 mm LFCSP
Supply operation: 3.0 V to 5.5 V @ 22 mA
Fabricated using high speed SiGe process
APPLICATIONS
RF transmitter PA setpoint control and level monitoring
Power monitoring in radio link transmitters
RSSI measurement in base stations, WLANs, WiMAX, and radars
FUNCTIONAL BLOCK DIAGRAM
GAIN
BIAS SLOPE
DET DET DET DET
INHI
INLO
IV
V
OU
T
IV VSET
CLPF
TADJ
V
POS
COMM
05541-001
Figure 1.
GENERAL DESCRIPTION
The AD8317 is a demodulating logarithmic amplifier, capable
of accurately converting an RF input signal to a corresponding
decibel-scaled output. It employs the progressive compression
technique over a cascaded amplifier chain, each stage of which
is equipped with a detector cell. The device can be used in either
measurement or controller modes. The AD8317 maintains
accurate log conformance for signals of 1 MHz to 8 GHz and
provides useful operation to 10 GHz. The input dynamic range
is typically 55 dB (re: 50 ) with less than ±3 dB error. The
AD8317 has 6 ns/10 ns response time (fall time/rise time) that
enables RF burst detection to a pulse rate of beyond 50 MHz.
The device provides unprecedented logarithmic intercept stability
vs. ambient temperature conditions. A supply of 3.0 V to 5.5 V
is required to power the device. Current consumption is typically
22 mA, and it decreases to 200 µA when the device is disabled.
The AD8317 can be configured to provide a control voltage to a
power amplifier or a measurement output from the VOUT pin.
Because the output can be used for controller applications, special
attention has been paid to minimize wideband noise. In this
mode, the setpoint control voltage is applied to the VSET pin.
The feedback loop through an RF amplifier is closed via VOUT,
the output of which regulates the output of the amplifier to a
magnitude corresponding to VSET. The AD8317 provides 0 V to
(VPOS − 0.1 V) output capability at the VOUT pin, suitable for
controller applications. As a measurement device, VOUT is
externally connected to VSET to produce an output voltage,
VOUT, that is a decreasing linear-in-dB function of the RF input
signal amplitude.
The logarithmic slope is 22 mV/dB, determined by the VSET
interface. The intercept is 15 dBm (re: 50 Ω, CW input) using
the INHI input. These parameters are very stable against supply
and temperature variations.
The AD8317 is fabricated on a SiGe bipolar IC process and is
available in a 2 mm × 3 mm, 8-lead LFCSP with an operating
temperature range of −40°C to +85°C.
AD8317* Product Page Quick Links
Last Content Update: 08/30/2016
Comparable Parts
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Documentation
Application Notes
AN-1040: RF Power Calibration Improves Performance of
Wireless Transmitters
Data Sheet
AD8317: 1 MHz to 10 GHz, 50 dB Log Detector/Controller
Data Sheet
Tools and Simulations
ADIsimPLL™
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Technical Articles
Design a Logamp RF Pulse Detector
Detecting Fast RF Bursts using Log Amps
Log Amps and Directional Couplers Enable VSWR
Detection
Make Precise Base-Station Power Measurements
Measurement and Control of RF Power, Part I
Measurement and Control of RF Power, Part II
Measurement and Control of RF Power, Part III
Measuring the RF Power in CDMA2000 and W-CDMA
High Power Amplifiers (HPAs)
Measuring VSWR and Gain in Wireless Systems
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AD8317 Material Declaration
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AD8317
Rev. B | Page 2 of 20
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Functional Block Diagram .............................................................. 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 5
ESD Caution .................................................................................. 5
Pin Configuration and Function Descriptions ............................. 6
Typical Performance Characteristics ............................................. 7
Theory of Operation ...................................................................... 10
Using the AD8317 .......................................................................... 11
Basic Connections ...................................................................... 11
Input Signal Coupling ................................................................ 11
Output Interface ......................................................................... 11
Setpoint Interface ....................................................................... 11
Temperature Compensation of Output Voltage ..................... 12
Measurement Mode ................................................................... 12
Setting the Output Slope in Measurement Mode .................. 13
Controller Mode ......................................................................... 13
Output Filtering .......................................................................... 15
Operation Beyond 8 GHz ......................................................... 15
Evaluation Board ............................................................................ 16
Die Information .............................................................................. 18
Outline Dimensions ....................................................................... 19
Ordering Guide .......................................................................... 19
REVISION HISTORY
3/08—Rev. A to Rev. B
Changes to Features .......................................................................... 1
Changes to General Description .................................................... 1
Changes to Measurement Mode Section ..................................... 12
Changes to Equation 12 ................................................................. 15
8/07—Rev. 0 to Rev. A
Changes to f = 8.0 GHz, ±1 dB Dynamic Range Parameter ....... 4
Changes to Table 2 ............................................................................ 6
Changes to Figure 20 ...................................................................... 10
Changes to Setpoint Interface Section and Figure 22 ................ 12
Changes Figure 27 .......................................................................... 13
Changes to Table 5 .......................................................................... 17
Added Die Information Section ................................................... 19
Changes to Ordering Guide .......................................................... 21
10/05—Revision 0: Initial Version
AD8317
Rev. B | Page 3 of 20
SPECIFICATIONS
VPOS = 3 V, CLPF = 1000 pF, TA = 25°C, 52.3 Ω termination resistor at INHI, unless otherwise noted.
Table 1.
Parameter Conditions Min Typ Max Unit
SIGNAL INPUT INTERFACE INHI (Pin 1)
Specified Frequency Range 0.001 10 GHz
DC Common-Mode Voltage VPOS − 0.6 V
MEASUREMENT MODE VOUT (Pin 5) shorted to VSET (Pin 4), sinusoidal
input signal
f = 900 MHz RTADJ = 18 kΩ
Input Impedance 1500||0.33 Ω||pF
±1 dB Dynamic Range TA = 25°C 50 dB
−40°C < TA < +85°C 46 dB
Maximum Input Level ±1 dB error −3 dBm
Minimum Input Level ±1 dB error −53 dBm
Slope1
−25 −22 −19.5 mV/dB
Intercept1
12 15 21 dBm
Output Voltage, High Power In PIN = −10 dBm 0.42 0.58 0.78 V
Output Voltage, Low Power In PIN = −40 dBm 1.00 1.27 1.40 V
f = 1.9 GHz RTADJ = 8 kΩ
Input Impedance 950||0.38 Ω||pF
±1 dB Dynamic Range TA = 25°C 50 dB
−40°C < TA < +85°C 48 dB
Maximum Input Level ±1 dB error −4.00 dBm
Minimum Input Level ±1 dB error −54 dBm
Slope1
−25 −22 −19.5 mV/dB
Intercept1
10 14 20 dBm
Output Voltage, High Power In PIN = −10 dBm 0.35 0.54 0.80 V
Output Voltage, Low Power In PIN = −35 dBm 0.75 1.21 1.35 V
f = 2.2 GHz RTADJ = 8 kΩ
Input Impedance 810||0.39 Ω||pF
±1 dB Dynamic Range TA = 25°C 50 dB
−40°C < TA < +85°C 47 dB
Maximum Input Level ±1 dB error −5 dBm
Minimum Input Level ±1 dB error −55 dBm
Slope1
−22 mV/dB
Intercept1
14 dBm
Output Voltage, High Power In PIN = −10 dBm 0.53 V
Output Voltage, Low Power In PIN = −40 dBm 1.20 V
f = 3.6 GHz RTADJ = 8 kΩ
Input Impedance 300||0.33 Ω||pF
±1 dB Dynamic Range TA = 25°C 42 dB
−40°C < TA < +85°C 40 dB
Maximum Input Level ±1 dB error −6 dBm
Minimum Input Level ±1 dB error −48 dBm
Slope1
−22 mV/dB
Intercept1
11 dBm
Output Voltage, High Power In PIN = −10 dBm 0.47 V
Output Voltage, Low Power In PIN = −40 dBm 1.16 V
AD8317
Rev. B | Page 4 of 20
Parameter Conditions Min Typ Max Unit
f = 5.8 GHz RTADJ = 500 Ω
Input Impedance 110||0.05 Ω||pF
±1 dB Dynamic Range TA = 25°C 50 dB
−40°C < TA < +85°C 48 dB
Maximum Input Level ±1 dB error −4 dBm
Minimum Input Level ±1 dB error −54 dBm
Slope1
−22 mV/dB
Intercept1
16 dBm
Output Voltage, High Power In PIN = −10 dBm 0.59 V
Output Voltage, Low Power In PIN = −40 dBm 1.27 V
f = 8.0 GHz RTADJ = open
Input Impedance 28||0.79 Ω||pF
±1 dB Dynamic Range TA = 25°C 44 dB
−40°C < TA < +85°C 35 dB
Maximum Input Level ±1 dB error −2 dBm
Minimum Input Level ±1 dB error −46 dBm
Slope2
−22 mV/dB
Intercept2
21 dBm
Output Voltage, High Power In PIN = −10 dBm 0.70 V
Output Voltage, Low Power In PIN = −40 dBm 1.39 V
OUTPUT INTERFACE VOUT (Pin 5)
Voltage Swing VSET = 0 V, RFIN = open VPOS − 0.1 V
V
SET = 1.7 V, RFIN = open 10 mV
Output Current Drive VSET = 0 V, RFIN = open 10 mA
Small Signal Bandwidth RFIN = −10 dBm, from CLPF to VOUT 140 MHz
Output Noise RFIN = 2.2 GHz, −10 dBm, fNOISE = 100 kHz,
CLPF = open
90 nV/√Hz
Fall Time Input level = no signal to −10 dBm, 90% to 10%,
CLPF = 8 pF
18 ns
Input level = no signal to −10 dBm, 90% to 10%,
CLPF = open, ROUT = 150 Ω
6 ns
Rise Time Input level = −10 dBm to no signal, 10% to 90%,
CLPF = 8 pF
20 ns
Input level = −10 dBm to no signal, 10% to 90%,
CLPF = open, ROUT = 150 Ω
10 ns
Video Bandwidth (or Envelope Bandwidth) 50 MHz
VSET INTERFACE VSET (Pin 4)
Nominal Input Range RFIN = 0 dBm, measurement mode 0.35 V
RFIN = −50 dBm, measurement mode 1.40 V
Logarithmic Scale Factor −45 dB/V
Input Resistance RFIN = −20 dBm, controller mode, VSET = 1 V 40 kΩ
TADJ INTERFACE TADJ (Pin 6)
Input Resistance TADJ = 0.9 V, sourcing 50 A 13 kΩ
Disable Threshold Voltage TADJ = open VPOS − 0.4 V
POWER INTERFACE VPOS (Pin 7)
Supply Voltage 3.0 5.5 V
Quiescent Current 18 22 30 mA
vs. Temperature −40°C ≤ TA ≤ +85°C 60 µA/°C
Disable Current TADJ = VPOS 200 µA
1 Slope and intercept are determined by calculating the best-fit line between the power levels of −40 dBm and −10 dBm at the specified input frequency.
2 Slope and intercept are determined by calculating the best-fit line between the power levels of −34 dBm and −16 dBm at 8.0 GHz.
AD8317
Rev. B | Page 5 of 20
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
Supply Voltage, VPOS 5.7 V
VSET Voltage 0 V to VPOS
Input Power (Single-Ended, Re: 50 Ω) 12 dBm
Internal Power Dissipation 0.73 W
θJA 55°C/W
Maximum Junction Temperature 125°C
Operating Temperature Range −40°C to +85°C
Storage Temperature Range −65°C to +150°C
Lead Temperature (Soldering, 60 sec) 260°C
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
AD8317
Rev. B | Page 6 of 20
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
1INHI
2
C
OMM
3CLPF
4VSET
8INLO
7VPOS
6TADJ
5VOUT
TOP VIEW
(Not to Scale)
AD8317
05541-002
Figure 2. Pin Configuration
Table 3. Pin Function Descriptions
Pin No. Mnemonic Description
1 INHI RF Input. Nominal input range of −50 dBm to 0 dBm, re: 50 Ω; ac-coupled RF input.
2 COMM Device Common. Connect to a low impedance ground plane.
3 CLPF Loop Filter Capacitor. In measurement mode, this capacitor sets the pulse response time and video bandwidth.
In controller mode, the capacitance on this node sets the response time of the error amplifier/integrator.
4 VSET Setpoint Control Input for Controller Mode or Feedback Input for Measurement Mode.
5 VOUT
Measurement and Controller Output. In measurement mode, VOUT provides a decreasing linear-in-dB
representation of the RF input signal amplitude. In controller mode, VOUT is used to control the gain of a VGA or
VVA with a positive gain sense (increasing voltage increases gain).
6 TADJ Temperature Compensation Adjustment. Frequency-dependent temperature compensation is set by connecting
a ground-referenced resistor to this pin.
7 VPOS Positive Supply Voltage: 3.0 V to 5.5 V.
8 INLO RF Common for INHI. AC-coupled RF common.
Paddle Internally connected to COMM; solder to a low impedance ground plane.
AD8317
Rev. B | Page 7 of 20
TYPICAL PERFORMANCE CHARACTERISTICS
VPOS = 3 V; TA = +25°C, −40°C, +85°C; CLPF = 1000 pF, unless otherwise noted. Black: +25°C; Blue: −40°C; Red: +85°C. Error is calculated
by using the best-fit line between PIN = −40 dBm and PIN = −10 dBm at the specified input frequency, unless otherwise noted
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
VOUT (V)
0.75
ERROR (dB)
–2.0
–1.5
0
0.5
1.0
1.5
2.0
–0.5
–1.0
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5
PIN (dBm)
05541-003
Figure 3. VOUT and Log Conformance vs. Input Amplitude at 900 MHz,
RTADJ = 18 kΩ
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
VOUT (V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5
PIN (dBm)
05541-004
Figure 4. VOUT and Log Conformance vs. Input Amplitude at 1.9 GHz,
RTADJ = 8 kΩ
05541-005
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5
0
0.25
0.50
0.75
1.00
1.25
1.50
1.75
P
IN
(dBm)
V
OUT
(V)
2.00
ERROR (dB)
–2.0
–1.5
0
0.5
1.0
1.5
2.0
–0.5
–1.0
Figure 5. VOUT and Log Conformance vs. Input Amplitude at 2.2 GHz,
RTADJ = 8 kΩ
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5
P
IN
(dBm)
05541-006
Figure 6. VOUT and Log Conformance vs. Input Amplitude at 3.6 GHz,
RTADJ = 8 kΩ
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5
P
IN
(dBm)
05541-007
Figure 7. VOUT and Log Conformance vs. Input Amplitude at 5.8 GHz,
RTADJ = 500 Ω
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5
P
IN
(dBm)
05541-008
Figure 8. VOUT and Log Conformance vs. Input Amplitude at 8.0 GHz,
RTADJ = Open, Error Calculated from PIN = −34 dBm to PIN = −16 dBm
AD8317
Rev. B | Page 8 of 20
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
P
IN
(dBm)
05541-009
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5 10
Figure 9. VOUT and Log Conformance vs. Input Amplitude at 900 MHz,
Multiple Devices, RTADJ = 18
0
0.25
0.50
1.00
1.25
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
2.00
1.50
1.75
P
IN
(dBm)
05541-010
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5 10
Figure 10. VOUT and Log Conformance vs. Input Amplitude at 1.9 GHz,
Multiple Devices, RTADJ = 8 kΩ
0
0.25
0.50
1.00
1.25
2.00
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
05541-011
P
IN
(dBm)
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5
1.75
1.50
Figure 11. VOUT and Log Conformance vs. Input Amplitude at 2.2 GHz,
Multiple Devices, RTADJ = 8 kΩ
–1.5
–1.0
–0.5
0
0.5
1.0
1.5
2.00
0
05541-012
P
IN
(dBm)
1.75
2.0
–2.0
ERROR (dB)
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5 10
V
OUT
(V)
0.25
0.50
0.75
1.00
1.25
1.50
Figure 12. VOUT and Log Conformance vs. Input Amplitude at 3.6 GHz,
Multiple Devices, RTADJ = 8 kΩ
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
P
IN
(dBm)
05541-013
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5 10
Figure 13. VOUT and Log Conformance vs. Input Amplitude at 5.8 GHz,
Multiple Devices, RTADJ = 500 Ω
0
0.25
0.50
1.00
1.25
1.50
2.00
V
OUT
(V)
0.75
–2.0
–1.5
0
0.5
1.0
1.5
2.0
ERROR (dB)
–0.5
–1.0
P
IN
(dBm)
05541-014
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5 10
1.75
Figure 14. VOUT and Log Conformance vs. Input Amplitude at 8.0 GHz,
Multiple Devices, RTADJ = Open,
Error Calculated from PIN = −34 dBm to PIN = −16 dBm
AD8317
Rev. B | Page 9 of 20
0
j2
j1
–j1
–j2
j0.5
–j0.5
j0.2
–j0.2
0.2 0.5 1 2
8000MHz
10000MHz 5800MHz
3600MHz
2200MHz
1900MHz
900MHz
100MHz
START FREQUENCY = 0.05GHz
STOP FREQUENCY = 10GHz
05541-015
Figure 15. Input Impedance vs. Frequency; No Termination Resistor on INHI
(Impedance De-Embedded to Input Pins), Z0 = 50 Ω
A Ch3 620mV
3
05541-017
Ch3 500mV Ch4 200mV M4.00µs
T 12.7560µs
4
Δ : 1.86V
@ : 1.69V
Figure 16. Power-On/Power-Off Response Time; VPOS = 3.0 V;
Input AC-Coupling Capacitors = 10 pF; CLPF = Open
CH1 200mV
05541-016
M20.0ns A CH1 1.40V
T 943.600ns
CH1 RISE
10.44ns
CH1 FALL
6.113ns
Figure 17. VOUT Pulse Response Time; Pulsed RF Input 0.1 GHz, −10 dBm;
CLPF = Open; RLOAD = 150 Ω
05541-018
1k 10k 100k 1M
10
100
1000
10000
10M
NOISE SPECTRAL DENSITY (nV/ Hz)
–20dBm
0dBm
–60dBm
RF OFF
–40dBm
FREQUENCY (Hz)
–10dBm
Figure 18. Noise Spectral Density of Output; CLPF = Open
05541-019
1k 10k 100k 1M
10
100
1000
10000
10M
NOISE SPECTRAL DENSITY (nV/ Hz)
FREQUENCY (Hz)
Figure 19. Noise Spectral Density of Output Buffer (from CLPF to VOUT);
CLPF = 0.1 μF
0
0.25
0.50
1.00
1.25
1.50
1.75
2.00
V
OUT
(V)
0.75
ERROR (dB)
–2.0
–1.5
0
0.5
1.0
1.5
2.0
–0.5
–1.0
–55 –45 –35 –25 –15 –5 5 15
P
IN
(dBm)
–65
3.3V
3.0V
3.6V
05541-020
Figure 20. Output Voltage Stability vs. Supply Voltage at 1.9 GHz
When VPOS Varies by 10%
AD8317
Rev. B | Page 10 of 20
THEORY OF OPERATION
The AD8317 is a 6-stage demodulating logarithmic amplifier,
specifically designed for use in RF measurement and power
control applications at frequencies up to 10 GHz. A block
diagram is shown in Figure 21. Sharing much of its design
with the AD8318 logarithmic detector/controller, the AD8317
maintains tight intercept variability vs. temperature over a 50 dB
range. Additional enhancements over the AD8318, such as a
reduced RF burst response time of 6 ns to 10 ns, 22 mA supply
current, and board space requirements of only 2 mm × 3 mm,
add to the low cost and high performance benefits of the AD8317.
GAIN
BIAS SLOPE
DET DET DET DET
INHI
INLO
IV
V
OU
T
VSET
CLPF
TADJ
V
POS
COMM
05541-021
IV
Figure 21. Block Diagram
A fully differential design, using a proprietary, high speed SiGe
process, extends high frequency performance. Input INHI receives
the signal with a low frequency impedance of nominally 500 Ω
in parallel with 0.7 pF. The maximum input with ±1 dB log-
conformance error is typically 0 dBm (re: 50 Ω). The noise
spectral density referred to the input is 1.15 nV/Hz, which is
equivalent to a voltage of 118 µV rms in a 10.5 GHz bandwidth
or a noise power of −66 dBm (re: 50 Ω). This noise spectral
density sets the lower limit of the dynamic range. However,
the low end accuracy of the AD8317 is enhanced by specially
shaping the demodulating transfer characteristic to partially
compensate for errors due to internal noise. The common pin,
COMM, provides a quality low impedance connection to the
printed circuit board (PCB) ground. The package paddle, which
is internally connected to the COMM pin, should also be grounded
to the PCB to reduce thermal impedance from the die to the PCB.
The logarithmic function is approximated in a piecewise fashion
by six cascaded gain stages. (For a more comprehensive expla-
nation of the logarithm approximation, see the AD8307 data
sheet.) The cells have a nominal voltage gain of 9 dB each and a
3 dB bandwidth of 10.5 GHz. Using precision biasing, the gain
is stabilized over temperature and supply variations. The overall
dc gain is high, due to the cascaded nature of the gain stages. An
offset compensation loop is included to correct for offsets
within the cascaded cells. At the output of each of the gain
stages, a square-law detector cell is used to rectify the signal.
The RF signal voltages are converted to a fluctuating differential
current having an average value that increases with signal level.
Along with the six gain stages and detector cells, an additional
detector is included at the input of the AD8317, providing a
50 dB dynamic range in total. After the detector currents are
summed and filtered, the following function is formed at the
summing node:
ID × log10(VIN/VINTERCEPT) (1)
where:
ID is the internally set detector current.
VIN is the input signal voltage.
VINTERCEPT is the intercept voltage (that is, when VIN = VINTERCEPT,
the output voltage would be 0 V, if it were capable of going to 0 V).
AD8317
Rev. B | Page 11 of 20
USING THE AD8317
BASIC CONNECTIONS
The AD8317 is specified for operation up to 10 GHz; as a result,
low impedance supply pins with adequate isolation between
functions are essential. A power supply voltage of between 3.0 V
and 5.5 V should be applied to VPOS. Power supply decoupling
capacitors of 100 pF and 0.1 µF should be connected close to
this power supply pin.
AD8317
1 2 3 4
8 7 6 5
SIGNAL
INPUT
V
OUT
C2
C1
C5
C4
47nF
47nF
100pF
V
S
(3.0
V
TO 5.5V)
INHI
INLO VPOS TADJ VOUT
COMM CLPF VSET
05541-022
0.1µF R2
0
R1
52.3
R4
0
1
1
SEE THE TEMPERATURE COMPENSATION OF OUTPUT VOLTAGE SECTION.
2
SEE THE OUTPUT FILTERING SECTION.
2
Figure 22. Basic Connections
The paddle of the LFCSP package is internally connected to
COMM. For optimum thermal and electrical performance, the
paddle should be soldered to a low impedance ground plane.
INPUT SIGNAL COUPLING
The RF input (INHI) is single-ended and must be ac-coupled.
INLO (input common) should be ac-coupled to ground.
Suggested coupling capacitors are 47 nF ceramic 0402-style
capacitors for input frequencies of 1 MHz to 10 GHz. The
coupling capacitors should be mounted close to the INHI and
INLO pins. The coupling capacitor values can be increased to
lower the high-pass cutoff frequency of the input stage. The
high-pass corner is set by the input coupling capacitors and the
internal 10 pF high-pass capacitor. The dc voltage on INHI and
INLO is approximately one diode voltage drop below VPOS.
05541-023
V
POS
2kA = 9dB
18.7k18.7k
CURRENT
gm
STAGE
INLO
INHI
OFFSET
COMP
5pF 5pF
FIRST
GAIN
STAGE
Figure 23. Input Interface
While the input can be reactively matched, in general, this is not
necessary. An external 52.3 Ω shunt resistor (connected on the
signal side of the input coupling capacitors, as shown in
Figure 22) combines with the relatively high input impedance to
give an adequate broadband 50 Ω match.
The coupling time constant, 50 × CC/2, forms a high-pass
corner with a 3 dB attenuation at fHP = 1/(2π × 50 × CC ), where
C1 = C2 = CC. Using the typical value of 47 nF, this high-pass
corner is ~68 kHz. In high frequency applications, fHP should be
as large as possible to minimize the coupling of unwanted low
frequency signals. In low frequency applications, a simple RC
network forming a low-pass filter should be added at the input
for similar reasons. This low-pass filter network should generally
be placed at the generator side of the coupling capacitors, thereby
lowering the required capacitance value for a given high-pass
corner frequency.
OUTPUT INTERFACE
The VOUT pin is driven by a PNP output stage. An internal
10 Ω resistor is placed in series with the output and the VOUT
pin. The rise time of the output is limited mainly by the slew
on CLPF. The fall time is an RC-limited slew given by the load
capacitance and the pull-down resistance at VOUT. There is an
internal pull-down resistor of 1.6 kΩ. A resistive load at VOUT
is placed in parallel with the internal pull-down resistor to
provide additional discharge current.
05541-024
+
0.8V 1200
400
10
V
OU
T
V
POS
CLPF
C
OMM
Figure 24. Output Interface
To reduce the fall time, VOUT should be loaded with a resistive
load of <1.6 kΩ. For example, with an external load of 150 Ω,
the AD8317 fall time is <7 ns.
SETPOINT INTERFACE
The VSET input drives the high impedance (40 kΩ) input of an
internal op amp. The VSET voltage appears across the internal
1.5 kΩ resistor to generate ISET. When a portion of VOUT is
applied to VSET, the feedback loop forces
−ID × log10(VIN/VINTERCEPT) = ISET (2)
If VSET = VOUT/2x, then ISET = VOUT/(2x × 1.5 kΩ).
The result is
VOUT = (−ID × 1.5 kΩ × 2x) × log10(VIN/VINTERCEPT)
05541-025
1.5k
I
SET
COMM
V
SET
V
SET
COMM
20k
20k
Figure 25. VSET Interface
AD8317
Rev. B | Page 12 of 20
The slope is given by
ID × 2x × 1.5 kΩ = −22 mV/dB × x
For example, if a resistor divider to ground is used to generate a
VSET voltage of VOUT/2, x = 2. The slope is set to −880 V/decade
or −44 mV/dB.
TEMPERATURE COMPENSATION OF OUTPUT
VOLTAGE
The primary component of the variation in VOUT vs. temperature,
as the input signal amplitude is held constant, is the drift of the
intercept. This drift is also a weak function of the input signal
frequency; therefore, provision is made for the optimization of
internal temperature compensation at a given frequency by
providing Pin TADJ.
COMM COMM
I
COMP
V
INTERNAL
TADJ
R
TADJ
05541-026
1.5k
AD8317
Figure 26. TADJ Interface
RTADJ is connected between TADJ and ground. The value of
this resistor partially determines the magnitude of an analog
correction coefficient, which is used to reduce intercept drift.
The relationship between output temperature drift and
frequency is not linear and cannot be easily modeled. As a
result, experimentation is required to choose the correct
TADJ resistor. Table 4 shows the recommended values for
some commonly used frequencies.
Table 4. Recommended RTADJ Values
Frequency Recommended RTADJ
50 MHz 18 kΩ
100 MHz 18 kΩ
900 MHz 18 kΩ
1.8 GHz 8 kΩ
1.9 GHz 8 kΩ
2.2 GHz 8 kΩ
3.6 GHz 8 kΩ
5.3 GHZ 500 Ω
5.8 GHz 500 Ω
8 GHz Open
MEASUREMENT MODE
When the VOUT voltage or a portion of the VOUT voltage is fed
back to the VSET pin, the device operates in measurement
mode. As seen in Figure 27, the AD8317 has an offset voltage,
a negative slope, and a VOUT measurement intercept at the high
end of its input signal range.
0
0.25
0.50
0.75
1.00
1.25
1.50
2.00
V
OUT
(V)
–1.5
–1.0
–0.5
0
0.5
1.0
1.5
2.0
–60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5 0 5 10 15
P
IN
(dBm)
05541-027
RANGE FOR
CALCULATION OF
SLOPE AND INTERCEPT
V
OUT
IDEAL
V
OUT
25°C
ERROR 25°C
1.75
INTERCEPT
Figure 27. Typical Output Voltage vs. Input Signal
The output voltage vs. input signal voltage of the AD8317 is
linear-in-dB over a multidecade range. The equation for this
function is
VOUT = X × VSLOPE/DEC × log10(VIN/VINTERCEPT) (3)
= X × VSLOPE/dB × 20 × log10(VIN/VINTERCEPT) (4)
where:
X is the feedback factor in VSET = VOUT/X.
VSLOPE/DEC is nominally −440 mV/decade, or −22 mV/dB.
VINTERCEPT is the x-axis intercept of the linear-in-dB portion of
the VOUT vs. PIN curve (see Figure 27).
VINTERCEPT is 2 dBV for a sinusoidal input signal.
An offset voltage, VOFFSET, of 0.35 V is internally added to
the detector signal, so that the minimum value for VOUT is
X × VOFFSET; therefore, for X = 1, the minimum VOUT is 0.35 V.
The slope is very stable vs. process and temperature variation.
When base-10 logarithms are used, VSLOPE/DECADE represents the
volts/decade. A decade corresponds to 20 dB; VSLOPE/DECADE/20 =
VSLOPE/dB represents the slope in volts/dB.
As noted in Equation 3 and Equation 4, the VOUT voltage has a
negative slope. This is also the correct slope polarity to control
the gain of many power amplifiers in a negative feedback con-
figuration. Because both the slope and intercept vary slightly
with frequency, it is recommended to refer to the Specifications
section for application-specific values for slope and intercept.
Although demodulating log amps respond to input signal
voltage, not input signal power, it is customary to discuss the
amplitude of high frequency signals in terms of power. In this
case, the characteristic impedance of the system, Z0, must be
known to convert voltages to their corresponding power levels.
The following equations are used to perform this conversion:
P [dBm] = 10 × log10(VRMS2/(Z0 × 1 mW)) (5)
P [dBV] = 20 × log10(VRMS/1 VRMS) (6)
P [dBm] = P [dBV] − 10 × log10(Z0 × 1 mW/1 VRMS2) (7)
AD8317
Rev. B | Page 13 of 20
For example, PINTERCEPT for a sinusoidal input signal expressed in
terms of dBm (decibels referred to 1 mW), in a 50 Ω system is
PINTERCEPT [dBm] =
PINTERCEPT [dBV] − 10 × log10(Z0 × 1 mW/1 VRMS2) =
2 dBV − 10 × log10(50 × 10−3) = 15 dBm (8)
For a square wave input signal in a 200 Ω system,
PINTERCEPT =
−1 dBV − 10 × log10[(200 Ω × 1 mW/1 VRMS2)] = 6 dBm
Further information on the intercept variation dependence
upon waveform can be found in the AD8313 and AD8307
data sheets.
SETTING THE OUTPUT SLOPE IN MEASUREMENT
MODE
To operate in measurement mode, VOUT must be connected
to VSET. Connecting VOUT directly to VSET yields the nominal
logarithmic slope of approximately −22 mV/dB. The output
swing corresponding to the specified input range is then approx-
imately 0.35 V to 1.7 V. The slope and output swing can be
increased by placing a resistor divider between VOUT and
VSET (that is, one resistor from VOUT to VSET and one
resistor from VSET to ground). The input impedance of VSET
is approximately 40 kΩ. Slope-setting resistors should be kept
below 20 kΩ to prevent this input impedance from affecting
the resulting slope. If two equal resistors are used (for example,
10 kΩ/10 kΩ), the slope doubles to approximately −44 mV/dB.
05541-028
VOUT
AD8317
–44mV/dB
VSET
10k
10k
Figure 28. Increasing the Slope
CONTROLLER MODE
The AD8317 provides a controller mode feature at the VOUT
pin. By using VSET for the setpoint voltage, it is possible for the
AD8317 to control subsystems, such as power amplifiers (PAs),
variable gain amplifiers (VGAs), or variable voltage attenuators
(VVAs), that have output power that increases monotonically
with respect to their gain control signal.
To operate in controller mode, the link between VSET and
VOUT is broken. A setpoint voltage is applied to the VSET
input, VOUT is connected to the gain control terminal of the
VGA, and the RF input of the detector is connected to the
output of the VGA (usually using a directional coupler and
some additional attenuation). Based on the defined relationship
between VOUT and the RF input signal when the device is in
measurement mode, the AD8317 adjusts the voltage on VOUT
(VOUT is now an error amplifier output) until the level at the
RF input corresponds to the applied VSET. When the AD8317
operates in controller mode, there is no defined relationship
between the VSET and the VOUT voltage; VOUT settles to a value
that results in the correct input signal level appearing at
INHI/INLO.
For this output power control loop to be stable, a ground-
referenced capacitor must be connected to the CLPF pin. This
capacitor, CFLT, integrates the error signal (in the form of a
current) to set the loop bandwidth and ensure loop stability.
Further details on control loop dynamics can be found in the
AD8315 data sheet.
05541-029
RFIN
VGA/VVA
GAIN
CONTROL
VOLTAGE
DIRECTIONAL
COUPLER
ATT ENUATOR
INHI
VSET
INLO
CLPF
VOUT
AD8317
52.3
47nF
C
FLT
47nF
DAC
Figure 29. Controller Mode
Decreasing VSET, which corresponds to demanding a higher
signal from the VGA, increases VOUT. The gain control voltage
of the VGA must have a positive sense. A positive control
voltage to the VGA increases the gain of the device.
The basic connections for operating the AD8317 in an auto-
matic gain control (AGC) loop with the ADL5330 are shown in
Figure 30. The ADL5330 is a 10 MHz to 3 GHz VGA. It offers a
large gain control range of 60 dB with ±0.5 dB gain stability.
This configuration is similar to Figure 29.
The gain of the ADL5330 is controlled by the output pin of the
AD8317. This voltage, VOUT, has a range of 0 V to near VPOS. To
avoid overdrive recovery issues, the AD8317 output voltage can
be scaled down using a resistive divider to interface with the 0 V
to 1.4 V gain control range of the ADL5330.
A coupler/attenuation of 21 dB is used to match the desired
maximum output power from the VGA to the top end of the
linear operating range of the AD8317 (approximately −5 dBm
at 900 MHz).
AD8317
Rev. B | Page 14 of 20
INLO
INHI
GAIN
OPLO
OPHI
DIRECTIONAL
COUPLER
ATT ENUATOR
VPSx COMx
ADL5330
+5
+5V
+5
COMM
VOUT VPOS
VSET INHI
INLOCLPF
AD8317
LOG AMP
DAC
RF OUTPUT
SIGNAL
4.12k
10k
SETPOINT
VOLTAGE
1nF
47nF
47nF
120nH
120nH
100pF
100pF
100pF
100pF
TADJ
18k
52.3
RF INPUT
SIGNAL
05541-030
Figure 30. AD8317 Operating in Controller Mode to Provide Automatic Gain Control Functionality in Combination with the ADL5330
Figure 31 shows the transfer function of the output power vs.
the setpoint voltage over temperature for a 900 MHz sine wave
with an input power of −1.5 dBm. Note that the power control
of the AD8317 has a negative sense. Decreasing VSET, which
corresponds to demanding a higher signal from the ADL5330,
increases gain.
The AGC loop is capable of controlling signals just under the
full 60 dB gain control range of the ADL5330. The performance
over temperature is most accurate over the highest power range,
where it is generally most critical. Across the top 40 dB range
of output power, the linear conformance error is well within
±0.5 dB over temperature.
–50
–40
–30
–10
0
10
20
30
OUTPUT POWER (dBm)
ERROR (dB)
–20
–4
–3
0
1
2
3
4
–1
–2
0.2 0.4 0.6 0.8 1.0 1.4 1.8
2.0
SETPOINT VOLTAGE (V)
1.61.2
05541-031
Figure 31. ADL5330 Output Power vs. AD8317 Setpoint Voltage, PIN = −1.5 dBm
For the AGC loop to remain in equilibrium, the AD8317 must
track the envelope of the ADL5330 output signal and provide
the necessary voltage levels to the ADL5330 gain control input.
Figure 32 shows an oscilloscope screenshot of the AGC loop
depicted in Figure 30. A 100 MHz sine wave with 50% AM
modulation is applied to the ADL5330. The output signal from
the VGA is a constant envelope sine wave with amplitude corre-
sponding to a setpoint voltage at the AD8317 of 1.5 V. Also
shown is the gain control response of the AD8317 to the
changing input envelope.
CH1 200mV
CH3 50.0mVA CH2 820mV
05541-032
M2.00ms
T 640.00µs
1
3
2
AM MODULATED INPUT
AD8317 OUTPUT
ADL5330 OUTPUT
Ch2 200mV
Figure 32. Oscilloscope Screenshot Showing an AM Modulated Input Signal
and the Response from the AD8317
AD8317
Rev. B | Page 15 of 20
Figure 33 shows the response of the AGC RF output to a pulse
on VSET. As VSET decreases from 1.7 V to 0.4 V, the AGC loop
responds with an RF burst. In this configuration, the input
signal to the ADL5330 is a 1 GHz sine wave at a power level
of −15 dBm.
05541-033
A CH1 2.48V
T 699.800µs
AD8317 VSET PULSE
ADL5330 OUTPUT
2
1
T
M10.0µsCH1 2.00V CH2 50mV
Figure 33. Oscilloscope Screenshot Showing
the Response Time of the AGC Loop
Response time and the amount of signal integration are con-
trolled by CFLT. This functionality is analogous to the feedback
capacitor around an integrating amplifier. Although it is
possible to use large capacitors for CFLT, in most applications,
values under 1 nF provide sufficient filtering.
Calibration in controller mode is similar to the method used
in measurement mode. A simple 2-point calibration can be
done by applying two known VSET voltages or DAC codes and
measuring the output power from the VGA. Slope and intercept
can then be calculated by:
Slope = (VSET1VSET2)/(POUT1POUT2) (9)
Intercept = POUT1VSET1/Slope (10)
VSETx = Slope × (POUTXIntercept) (11)
More information on the use of the ADL5330 in AGC applica-
tions can be found in the ADL5330 data sheet.
OUTPUT FILTERING
For applications in which maximum video bandwidth and,
consequently, fast rise time are desired, it is essential that the
CLPF pin be left unconnected and free of any stray capacitance.
The nominal output video bandwidth of 50 MHz can be reduced
by connecting a ground-referenced capacitor (CFLT) to the CLPF
pin, as shown in Figure 34. This is generally done to reduce
output ripple (at twice the input frequency for a symmetric
input waveform such as sinusoidal signals).
+4 VOUT
CLPF
AD8317
3.5pF
05541-037
I
LOG
C
FLT
1.5k
Figure 34. Lowering the Postdemodulation Bandwidth
CFLT is selected by
pF5.3
)k5.12(
1
××
=
BandwidthVideo
CFLT
π
(12)
The video bandwidth should typically be set to a frequency
equal to about one-tenth the minimum input frequency. This
ensures that the output ripple of the demodulated log output,
which is at twice the input frequency, is well filtered.
In many log amp applications, it may be necessary to lower
the corner frequency of the postdemodulation filter to achieve
low output ripple while maintaining a rapid response time to
changes in signal level. An example of a 4-pole active filter is
shown in the AD8307 data sheet.
OPERATION BEYOND 8 GHz
The AD8317 is specified for operation up to 8 GHz, but it provides
useful measurement accuracy over a reduced dynamic range of
up to 10 GHz. Figure 35 shows the performance of the AD8317
over temperature at 10 GHz when the device is configured as
shown in Figure 22. Dynamic range is reduced at this frequency,
but the AD8317 does provide 30 dB of measurement range
within ±3 dB of linearity error.
05541-038
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
–40 –35 –30 –25 –20 –15 –10 –5 0 5
P
IN
(dBm)
V
OUT
(V)
–5
–4
–3
–2
–1
0
1
2
3
4
5
ERROR (dB)
Figure 35. VOUT and Log Conformance vs. Input Amplitude at 10.0 GHz,
Multiple Devices, RTADJ = Open, CLPF = 1000 pF
Implementing an impedance match for frequencies beyond
8 GHz can improve the sensitivity of the AD8317 and measure-
ment range.
Operation beyond 10 GHz is possible, but part-to-part
variation, most notably in the intercept, becomes significant.
AD8317
Rev. B | Page 16 of 20
EVALUATION BOARD
Table 5. Evaluation Board (Rev. A) Configuration Options
Component Function Default Conditions
VPOS, GND Supply and Ground Connections. Not applicable
R1, C1, C2 Input Interface.
The 52.3 Ω resistor in Position R1 combines with the internal input impedance
of the AD8317 to give a broadband input impedance of about 50 Ω. C1 and C2
are dc-blocking capacitors. A reactive impedance match can be implemented
by replacing R1 with an inductor and C1 and C2 with appropriately valued
capacitors.
R1 = 52.3 Ω (Size 0402)
C1 = 47 nF (Size 0402)
C2 = 47 nF (Size 0402)
R5, R7 Temperature Compensation Interface.
The internal temperature compensation network is optimized for input signals
up to 3.6 GHz when R7 is 10 kΩ. This circuit can be adjusted to optimize
performance for other input frequencies by changing the value of the resistor
in Position R7. See Table 4 for specific RTADJ resistor values.
R5 = 200 Ω (Size 0402)
R7 = open (Size 0402)
R2, R3, R4, R6, RL, CL Output Interface—Measurement Mode.
In measurement mode, a portion of the output voltage is fed back to the VSET
pin via R2. The magnitude of the slope of the VOUT output voltage response
can be increased by reducing the portion of VOUT that is fed back to VSET. R6
can be used as a back-terminating resistor or as part of a single-pole, low-pass
filter.
R2 = 0 Ω (Size 0402)
R3 = open (Size 0402)
R4 = open (Size 0402)
R6 = 1 kΩ (Size 0402)
RL = CL = open (Size 0402)
R2, R3 Output Interface—Controller Mode.
In this mode, R2 must be open. In controller mode, the AD8317 can control the
gain of an external component. A setpoint voltage is applied to Pin VSET, the
value of which corresponds to the desired RF input signal level applied to the
AD8317 RF input. A sample of the RF output signal from this variable gain
component is selected, typically via a directional coupler, and applied to the
AD8317 RF input. The voltage at the VOUT pin is applied to the gain control of
the variable gain element. A control voltage is applied to the VSET pin. The
magnitude of the control voltage can optionally be attenuated via the voltage
divider comprising R2 and R3, or a capacitor can be installed in Position R3 to
form a low-pass filter along with R2.
R2 = open (Size 0402)
R3 = open (Size 0402)
C4, C5 Power Supply Decoupling.
The nominal supply decoupling consists of a 100 pF filter capacitor placed
physically close to the AD8317 and a 0.1 µF capacitor placed nearer to the
power supply input pin.
C4 = 0.1 µF (Size 0603)
C5 = 100 pF (Size 0402)
C3 Filter Capacitor.
The low-pass corner frequency of the circuit that drives the VOUT pin can be
lowered by placing a capacitor between CLPF and ground. Increasing this
capacitor increases the overall rise/fall time of the AD8317 for pulsed input
signals. See the Output Filtering section for more details.
C3 = 8.2 pF (Size 0402)
AD8317
1 2 3 4
8 7 6 5
R1
52.3
R7
OPEN
R2
0
C1
C2
C4
C5
47nF
47nF
0.1µF
100pF
V
POS
INHI
INLO VPOS TADJ VOUT
COMM CLPF VSET
05541-034
T
A
DJ
R5
200
R4
OPEN
VOUT_ALT
R3
OPEN
CL
OPEN
RL
OPEN
R6
1k
GND
RFIN
VSET
VOU
T
C3
8.2pF
Figure 36. Evaluation Board Schematic
AD8317
Rev. B | Page 17 of 20
05541-035
Figure 37. Component Side Layout
05541-036
Figure 38. Component Side Silkscreen
AD8317
Rev. B | Page 18 of 20
DIE INFORMATION
05541-039
BOND PAD STATISTICS
ALL MEASURMENTS IN MICRONS.
MINIMUM PASSIVATION OPENING: 59 × 59 MIN PAD PITCH: 89
DIE SIZE CALCULATION
ALL MEASURMENTS IN MICRONS.
DIEX (WIDTH OF DIE IN X DIRECTION) = 670
DIEY (WIDTH OF DIE IN Y DIRECTION) = 1325
DIE THICKNESS = 305 MICRONS
BALL BOND SHEAR STRENGTH SPECIFICATION: MINIMUM 15 GRAMS
1
2
2
3
4
5
6
7
8
Y
X
DB1
ADI AD8317
Figure 39. Die Outline Dimensions
Table 6. Die Pad Function Descriptions
Pin No. Mnemonic Description
1 INHI RF Input. Nominal input range of −50 dBm to 0 dBm, re: 50 Ω; ac-coupled RF input.
2, 2 COMM Device Common. Connect both pads to a low impedance ground plane.
3 CLPF Loop Filter Capacitor. In measurement mode, this capacitor sets the pulse response time and video
bandwidth. In controller mode, the capacitance on this node sets the response time of the error
amplifier/integrator.
4 VSET Setpoint Control Input for Controller Mode or Feedback Input for Measurement Mode.
5 VOUT
Measurement and Controller Output. In measurement mode, VOUT provides a decreasing linear-in dB
representation of the RF input signal amplitude. In controller mode, VOUT is used to control the gain of
a VGA or VVA with a positive gain sense (increasing voltage increases gain).
6 TADJ Temperature Compensation Adjustment. Frequency-dependent temperature compensation is set by
connecting a ground-referenced resistor to this pin.
7 VPOS Positive Supply Voltage: 3.0 V to 5.5 V.
8 INLO RF Common for INHI. AC-coupled RF common.
DB1 COMM Device Common. Connect to a low impedance ground plane.
AD8317
Rev. B | Page 19 of 20
031207-A
OUTLINE DIMENSIONS
0.30
0.23
0.18
SEATING
PLANE 0.20 REF
0.80 MAX
0.65 TYP
1.00
0.85
0.80
1.89
1.74
1.59
0.50 BSC
0.60
0.45
0.30
0.55
0.40
0.30
0.15
0.10
0.05
0.25
0.20
0.15
BOTTOM VIEW
41
58
3.25
3.00
2.75
1.95
1.75
1.55
2.95
2.75
2.55
PIN 1
INDI
C
ATOR
2.25
2.00
1.75
TOP VIEW
0.05 MAX
0.02 NOM
12° MAX
EXPOSEDPAD
Figure 40. 8-Lead Lead Frame Chip Scale Package [LFCSP_VD]
2 mm × 3 mm Body, Very Thin, Dual Lead
(CP-8-1)
Dimensions shown in millimeters
ORDERING GUIDE
Model Temperature Range Package Description Package Option Branding
AD8317ACPZ-R71
−40°C to +85°C 8-Lead LFCSP_VD, 7” Tape and Reel CP-8-1 Q1
AD8317ACPZ-R21
−40°C to +85°C 8-Lead LFCSP_VD, 7” Tape and Reel CP-8-1 Q1
AD8317ACPZ-WP1
−40°C to +85°C 8-Lead LFCSP_VD, Waffle Pack CP-8-1 Q1
AD8317ACHIPS −40°C to +85°C Die
AD8317-EVALZ1
Evaluation Board
1 Z = RoHS Compliant Part.
AD8317
Rev. B | Page 20 of 20
NOTES
©2005–2008 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D05541-0-3/08(B)