LINER LT5570 Ultrafastâ ¢ 7ns response time 15ghz rf power detector with comparator Datasheet

LTC5564
UltraFast™ 7ns Response
Time 15GHz RF Power
Detector with Comparator
DESCRIPTION
FEATURES
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Temperature Compensated Schottky RF Peak Detector
Wide Input Frequency Range: 600MHz to 15GHz†
Wide Input Power Range: –24dBm to 16dBm
7ns Typical Response Time
75MHz Demodulation Bandwidth
Programmable Gain Settings for Improved Sensitivity
Adjustable Amplifier Output Offset Voltage
High Speed Comparator with Latch Enable: 9ns
Typical Response Time
16-Lead 3mm × 3mm QFN Package
APPLICATIONS
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RF Signal Presence Detectors for: 802.11a, 802.11b,
802.11g, 802.15, Optical Data Links, Wireless Data
Modems, Wireless and Cable Infrastructure
5.8GHz ISM Band Radios
MMDS Microwave Links
PA Power Supply Envelope Tracking Control
Fast Alarm
RF Power Monitor
Envelope Detector
Ultra-Wideband Radio
Radar Detector
The LTC®5564 is a precision, RF power detector for applications in the 600MHz to 15GHz frequency range. The
LTC5564 operates with input power levels from –24dBm
to 16dBm.
A temperature compensated Schottky diode peak detector,
gain-selectable operational amplifier, and fast comparator
are combined in a small 16-lead 3mm × 3mm QFN package.
The RF input signal is peak detected and then sensed by
both a comparator and amplifier. The comparator provides
a 9ns response time to input levels exceeding VREF along
with a latch enable/disable function. The gain selectable
operational amplifier provides a 350V/µs slew rate and
75MHz of demodulation bandwidth to the analog output.
VOUTADJ and VREF pins allow for the adjustment of VOUT
offset and VCOMP switch point voltages, respectively.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
UltraFast is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners.
†Higher frequency operation is achievable with reduced performance. Consult the factory for
more information.
TYPICAL APPLICATION
Demo Board Schematic Optimized for 15GHz
VCC
15GHz
RFIN
10pF
17
2.2pF
0.5pF
1
2
3
4
16
100pF
15
14
13
NC VCCRF VREF VCOMP
RFIN
VCCA
NC
VCCP
LTC5564
VOUT
GND
NC
GND
LEN VOUTADJ G0
5
LEN
6
VCOMP
VCC
12
10
68Ω
9 100pF
G1
7
8
10k
10k
G1
G0
VOUTADJ
10k
10pF
11
1000pF
VOUT
VOUT OUTPUT VOLTAGE (mV)
1000pF
VOUT vs Input Power 2.7GHz
VREF
3400
3200 VCC = 5V
3000 TA = 25°C
2800
2600
GAIN8
2400
2200
GAIN4
2000
1800
1600
1400
GAIN1
1200
1000
800
600
GAIN2
400
200
0
–24 –20 –16 –12 –8 –4 0 4 8 12 16
RFIN POWER (dBm)
5564 TA01b
5564 F05
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LTC5564
PIN CONFIGURATION
Supply Voltages
VCCRF = VCCA = VCCP.............................................5.8V
RFIN Voltage for VCCRF ≤ 5.5V.....................(VCCRF ± 2V)
RFIN Power ..........................................................16dBm
ICOMP, IVOUT.......................................................... ±10mA
VOUTADJ, VREF, VCOMP, VOUT, G0, G1, LEN....–0.3V to VCC
Operating Temperature Range (Note 2)....–40°C to 85°C
Max Junction Temperature................................... 125°C
Storage Temperature Range................... –65°C to 150°C
VCOMP
VREF
VCCRF
NC
TOP VIEW
16 15 14 13
RFIN 1
12 VCCA
NC 2
11 VCCP
17
GND
GND 3
10 VOUT
9 NC
5
6
7
8
G0
G1
GND 4
LEN
(Note 1)
VOUTADJ
ABSOLUTE MAXIMUM RATINGS
UD PACKAGE
16-LEAD (3mm × 3mm) PLASTIC QFN
TJMAX = 125°C, θJA = 68°C/W, θJC = 7.5°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LTC5564IUD#PBF
LTC5564IUD#TRPBF
LFRF
16-Lead (3mm × 3mm) Plastic QFN
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. Supply voltage = VCCRF = VCCA = VCCP = 5V, GAIN1, CLOAD = 10pF,
no RF input signal, unless otherwise noted.
PARAMETER
CONDITIONS
Supply Voltage
MIN
l
TYP
3.0
Supply Current
MAX
5.5
44
UNITS
V
mA
Amplifier Characteristics
VOUT Output Offset
Supply Voltage = 5V, No RFIN
GAIN1
GAIN2
GAIN4
GAIN8
Supply Voltage = 3.3V, No RFIN
GAIN1
GAIN2
GAIN4
GAIN8
l
l
195
195
290
295
315
360
395
395
mV
mV
mV
mV
l
l
185
185
280
280
290
315
385
385
mV
mV
mV
mV
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LTC5564
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. Supply voltage = VCCRF = VCCA = VCCP = 5V, GAIN1, CLOAD = 10pF,
no RF input signal, unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
VOUT Slew Rate Rise/Fall
Supply Voltage = 5V, VOUT 10% to 90%, ∆VOUT = 1.1V (Note 3)
GAIN1, Pin = 10dBm to 16dBm
GAIN2, Pin = 4dBm
GAIN4, Pin = –2dBm
GAIN8, Pin = –8dBm
350/70
185/70
120/70
50/50
V/µs
V/µs
V/µs
V/µs
Supply Voltage = 3.3V, VOUT 10% to 90%, ∆VOUT = 1.1V (Note 3)
GAIN1, Pin = 10dBm to 16dBm
GAIN2, Pin = 4dBm
GAIN4, Pin = –2dBm
GAIN8, Pin = –8dBm
325/70
185/70
120/70
50/50
V/µs
V/µs
V/µs
V/µs
75
52
35
15
MHz
MHz
MHz
MHz
Demodulation Bandwidth
(Notes 4, 5)
GAIN1, VOUT = 500mV
GAIN2, VOUT = 500mV
GAIN4, VOUT = 500mV
GAIN8, VOUT = 500mV
VOUTADJ Input Range
GAIN1 ∆VOUT = ±100mV (Note 5)
VOUT Load Capacitance
(Note 5)
VOUT Output Current
Sourcing, RL = 2k
VOUT Response Time
Supply Voltage = 5V, RFIN Step to 50% VOUT (Note 3)
GAIN1, Pin = 10dBm to 16dBm
GAIN2, Pin = 4dBm
GAIN4, Pin = –2dBm
GAIN8, Pin = –8dBm
7.0
9.0
11.0
14.0
ns
ns
ns
ns
Supply Voltage = 3.3V, RFIN Step to 50% VOUT (Note 3)
GAIN1, Pin = 10dBm to 16dBm
GAIN2, Pin = 4dBm
GAIN4, Pin = –2dBm
GAIN8, Pin = –8dBm
7.1
9.0
11.0
14.0
ns
ns
ns
ns
VOUT Output Voltage Swing
0/225
mV
10
1.7
Supply Voltage = 3V
pF
mA
1.4
V
Comparator Characteristics
Comparator Response Time
10dBm to 16dBm RFIN Step to VCOMP 50% (Note 3)
Comparator Hysteresis
IVREF Input Current
9
ns
10
mV
–2.3
µA
0.6 to 15
GHz
RF Characteristics
RFIN Frequency Range
(Note 6)
RFIN AC Input Resistance
Frequency = 1000MHz, Power Level = 0dBm
RFIN Input Shunt Capacitance
Frequency = 1000MHz, Power Level = 0dBm
RFIN Input Power Range
(Note 6)
135
Ω
0.77
pF
–24 to 16
dBm
Digital I/O
LEN VIL/VIH
0.8
VCCA – 0.8
V
G0 VIL/VIH
0.8
VCCA – 0.8
V
G1 VIL/VIH
0.8
VCCA – 0.8
V
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC5564 is guaranteed functional within the operating
temperature range from –40°C to 85°C.
Note 3: RFIN step from no power to stated level.
Note 4: See typical curve for bandwidth vs output voltage.
Note 5: See Applications Information section.
Note 6: Specification is guaranteed by design and not 100% tested in
production.
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LTC5564
TYPICAL PERFORMANCE CHARACTERISTICS
Demodulation Bandwidth
30 VOUT = 500mV
VOUT –3dB CROSSOVER (MHz)
20
GAIN (dB)
10
0
–10
–20
–30
–40
–50
0.01
GAIN8
GAIN4
GAIN2
GAIN1
0.1
VOUT Pulse Response, PIN = 8dBm
Demodulation Bandwidth vs VOUT
80
GAIN1
70
GAIN2
60
50
GAIN4
40
VOUT
500mV/DIV
ASK MODULATED RF
INPUT SIGNAL START
30
20
GAIN8
VCC = 5V
ASK MODULATION FREQUENCY 2.7GHz
GAIN1
10
1
10
FREQUENCY (MHz)
100
0
200
1000
85°C
250
300
350
25°C
400
–40°C
450
10ns/DIV
500
5564 G03
VOUT (mV)
5564 G01
5564 G02
VOUT Pulse Response = –10dBm
400
VOUT Offset vs Temperature
GAIN1
VOUT Offset vs Supply Voltage
350
GAIN8
GAIN4
GAIN2
GAIN1
310
VOUT (mV)
VOUT (mV)
ASK MODULATED RF
INPUT SIGNAL START
300
VCC = 5V
ASK MODULATION FREQUENCY 2.7GHz
GAIN1
AVERAGE
290
270
–3 STDEV
250
250
5564 G04
10ns/DIV
3 STDEV
330
350
VOUT
50mV/DIV
VCC = 5V
3.5
3
4
4.5
VCC (V)
5
230
–40
5.5
–20
20
40
0
TEMPERATURE (°C)
60
5564 G05
410
VCC = 5V
390
3 STDEV
310
VOUT (mV)
VOUT (mV)
330
AVERAGE
290
590
3 STDEV
540
370
490
350
440
330
AVERAGE
310
290
–3 STDEV
–20
20
40
0
TEMPERATURE (°C)
80
5565 G07
230
–40
390
3 STDEV
AVERAGE
340
240
–3 STDEV
250
60
VCC = 5V
290
270
270
250
–40
VCC = 5V
VOUT Offset vs Temperature
GAIN8
VOUT (mV)
350
5565 G06
VOUT Offset vs Temperature
GAIN4
VOUT Offset vs Temperature
GAIN2
80
–3 STDEV
190
–20
20
40
0
TEMPERATURE (°C)
60
80
5565 G08
140
–40
–20
20
40
0
TEMPERATURE (°C)
60
80
5565 G09
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LTC5564
TYPICAL PERFORMANCE CHARACTERISTICS
GAIN1, GAIN2
GAIN4, GAIN8
46
3600
VCC = 5V
GAIN1
4400
4000
VOUT OUTPUT VOLTAGE (mV)
2400
2000
40
1600
1200
38
36
800
–40°C
25°C
85°C
400
3.5
4
4.5
VCC (V)
5
5.5
5564 G10
VOUT vs Input Power 2.7GHz
2000
1600
1200
800
0
–10 –8 –6 –4 –2 0 2 4 6 8 10 12 14 16
RFIN POWER (dBm)
5564 G25
VOUT OUTPUT VOLTAGE (mV)
2800
–40°C
2800
2400
2000
VOUT vs Input Power 5.8GHz
VCC = 5V
GAIN1
2400
–40°C
2000
25°C
25°C
1600
1600
85°C
1200
1200
800
85°C
800
400
400
0
–10 –8 –6 –4 –2 0 2 4 6 8 10 12 14 16
RFIN POWER (dBm)
0
–10 –8 –6 –4 –2 0 2 4 6 8 10 12 14 16
RFIN POWER (dBm)
5564 G12
5564 G13
VOUT vs Input Power 10GHz
1600
VCC = 5V
GAIN1
TA = 25°C
1400
VOUT OUTPUT VOLTAGE (mV)
VOUT OUTPUT VOLTAGE (mV)
VOUT OUTPUT VOLTAGE (mV)
VCC = 5V
3200 GAIN1
VOUT vs Input Power 8GHz
2000
2400
3200
3600
5564 G11
2400
2800
5564 G24
VOUT vs Input Power 2.7GHz
3400
3200 VCC = 5V
3000 TA = 25°C
2800
2600
GAIN8
2400
2200
GAIN4
2000
1800
1600
1400
GAIN1
1200
1000
800
600
GAIN2
400
200
0
–24 –20 –16 –12 –8 –4 0 4 8 12 16
RFIN POWER (dBm)
3200
400
0
–10 –8 –6 –4 –2 0 2 4 6 8 10 12 14 16
RFIN INPUT POWER (dBm)
VOUT OUTPUT VOLTAGE (mV)
3
VCC = 5V
GAIN1
TA = 25°C
3600
2800
42
34
VOUT vs Input Power 1.9GHz
4800
3200
44
ICC (mA)
VOUT vs Input Power 700MHz
4000
VOUT OUTPUT VOLTAGE (mV)
Supply Current vs Supply Voltage
48
1200
1600
VCC = 5V
GAIN1
TA = 25°C
1000
1200
800
400
800
600
400
200
0
–10 –8 –6 –4 –2 0 2 4 6 8 10 12 14 16
RFIN INPUT POWER (dBm)
5564 G26
0
–24 –20 –16 –12 –8 –4 0 4
RFIN POWER (dBm)
8
12 16
5564 G27
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LTC5564
TYPICAL PERFORMANCE CHARACTERISTICS
VOUT vs Input Power 10GHz
VOUT vs Input Power 12GHz
1800
VCC = 5V
GAIN1
1600
GAIN8
3600
VOUT OUTPUT VOLTAGE (mV)
VOUT OUTPUT VOLTAGE (mV)
VCC = 5V
4400 T = 25°C
A
4000
1400
GAIN4
3200
1000
GAIN1
2400
–40°C
1200
GAIN2
2800
1000
2000
1600
1200
800
VOUT OUTPUT VOLTAGE (mV)
4800
25°C
800
600
85°C
400
800
VOUT vs Input Power 15GHz
VCC = 5V
GAIN1
TA = 25°C
600
400
200
400
0
–24 –20 –16 –12 –8 –4 0 4
RFIN POWER (dBm)
8
0
–10 –8 –6 –4 –2 0 2 4 6 8 10 12 14 16
RFIN POWER (dBm)
12 16
5564 G28
2800
Comparator Rising Edge
Threshold vs Frequency
2000
VCC = 5V
TA = 25°C
FREQUENCY = 2.7GHz
VCC = 5V
TA = 25°C
RFIN = 10dBm
1800
1600
RISING EDGE VREF (mV)
RISING THRESHOLD VOLTAGE (mV)
3200
5564 G29
5564 G14
Comparator Threshold Voltage
vs RF Input Power
3600
0
–10 –8 –6 –4 –2 0 2 4 6 8 10 12 14 16
RFIN INPUT POWER (dBm)
2400
1400
2000
1200
1600
1000
1200
VREF RISING
800
800
600
400
0
–10
–6
–2
2
6
10
RFIN POWER (dBm)
14
400
18
0
8000
12000
4000
FREQUENCY (MHz)
5564 G15
35
5564 G16
GAIN1 VOUT/RFIN Histogram
25
GAIN2 VOUT/RFIN Histogram
20
PERCENT OF UNITS (%)
PERCENT OF UNITS (%)
30
25
20
15
10
15
10
5
5
0
16000
1.32 1.33 1.34 1.35 1.36 1.37 1.38 1.39 1.40 1.41
GAIN (V/V)
5564 G17
0
2.710
2.750
2.790 2.830
GAIN (V/V)
2.870
2.910
5564 G18
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LTC5564
TYPICAL PERFORMANCE CHARACTERISTICS
GAIN4 VOUT/RFIN Histogram
GAIN8 VOUT/RFIN Histogram
20
GAIN2/GAIN1 Histogram
45
12
40
10
5
PERCENT OF UNITS (%)
PERCENT OF UNITS (%)
15
8
6
4
2
5.52
5.6
5.68
5.76
GAIN (V/V)
5.84
0
11.425 11.625 11.825 12.025 12.225 12.425
GAIN (V/V)
5.92
35
30
25
20
15
10
5
5564 G19
0
1.925
1.945
1.965 1.985
GAIN2/GAIN1
2.005
2.025
5564 G21
5564 G20
GAIN8/GAIN4 Histogram
GAIN4/GAIN2 Histogram
40
15
35
30
PERCENT OF UNITS (%)
0
PERCENT OF UNITS (%)
PERCENT OF UNITS (%)
10
25
20
15
10
10
5
5
0
1.980
2.005
2.030 2.055
GAIN4/GAIN2
2.080
2.105
5564 G22
0
2.045
2.065
2.085 2.105
GAIN8/GAIN4
2.125
2.145
5564 G23
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LTC5564
PIN FUNCTIONS
RFIN (Pin 1): RF Input Voltage. A coupling capacitor must
be used to connect to the RF signal source. This pin has
an internal 250Ω termination, an internal Schottky diode
detector and an internal 8pF reservoir capacitor.
G0, G1 (Pins 7, 8): Amplifier Gain Selection. Logic low or
high levels on the G0 and G1 pins will change the internal
amplifier gain, bandwidth and slew rate characteristics. See
the Applications Information section for gain setting codes.
NC (Pins 2, 9, 16): No Connect. These pins should be left
unconnected by the user for best RF performance.
VOUT (Pin 10): Detector Amplifier Output.
GND (Pins 3, 4, Exposed Pad Pin 17): These pins should
be tied to system ground. See Applications Information
for best practices.
VCCP (Pin 11): High Current Power Supply Pin.
VCCA (Pin 12): Analog Power Supply Pin.
VCOMP (Pin 13): Comparator Output.
LEN (Pin 5): Comparator Latch Enable Input. VCOMP will be
latched when LEN is high and transparent when LEN is low.
VREF (Pin 14): Comparator Negative Input. Apply an external reference voltage to this pin.
VOUTADJ (Pin 6): Amplifier Output Offset Adjust. When left
floating, the VOUT pin of the amplifier will be at its nominal
quiescent output offset value. See the Applications Information section for adjustment range.
VCCRF (Pin 15): RF Power Supply Pin.
SIMPLIFIED BLOCK DIAGRAM
VCCRF
RFIN
VCCA
VCCP
250Ω
8pF
80µA
1.2k
VP
VBIAS
LEN
+
–
VCOMP
+
–
VREF
VOUTADJ 1.7k
1.6k
200Ω
200Ω
+
–
VOUT
PROGRAMMABLE
FEEDBACK ARRAY
5564 F01
PINS 3, 4,
EXPOSED PAD PIN 17
G1
G0
Figure 1. Simplified Block Diagram
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LTC5564
APPLICATIONS INFORMATION
Operation
The LTC5564 is a fast RF detector with a high speed
amplifier and comparator. This product integrates these
functions to provide RF detection over frequencies ranging
from 600MHz to 15GHz. These functions include an RF
Schottky peak detector, internally compensated operational
amplifier, and a comparator as shown in Figure 1. The
LTC5564 has selectable amplifier gains, amplifier output
offset adjustment and comparator latch enable capabilities.
Amplifier
The high speed amplifier offers four gain settings and
is capable of driving a 1.7mA load with an output swing
range of approximately 295mV to VCC – 1.6V. See Table 1
for gain setting operation.
The VOUTADJ pin provides output DC offset adjustment
to satisfy various interface requirements. Setting VOUT
to 500mV also provides the maximum demodulation
bandwidth in each gain mode. See Electrical and Typical
Performance Characteristics curve. See Table 1 for the
typical VOUTADJ voltage for the desired VOUT DC output
offset in each gain setting.
RF Detector
The internal temperature compensated Schottky diode
peak detector converts the RF input signal to a low
frequency signal. The detector demonstrates excellent
efficiency and linearity over a wide range of input power
levels. The Schottky diode is nominally biased at 180µA
and drives a parallel reservoir capacitor-resistor network
of 8pF and 1.2k.
Comparator
The high speed comparator compares the external reference voltage on the VREF pin to the internal signal voltage
VP from the peak detector and produces the output logic
signal VCOMP . VP is the internal comparator positive input
as shown in Figure 1.
LEN provides latch enable/disable functionality as shown
in Figure 2.
Table 1. Gain Mode and Typical VOUTADJ Operation
PIN
G1
G0
GAIN MODE
DESCRIPTION
REQUIRED VOUTADJ FOR A GIVEN DC OUTPUT OFFSET
GND
GND
GAIN1
Minimum Gain Setting (VOUT/RFIN ≈ 1.5dB)
VOUTADJ = 0.95 • VOUT – 0.174
GND
VCCA
GAIN2
VOUT/RFIN Increased 6dB
VOUTADJ = (VOUT – 0.07)/2.10
VCCA
GND
GAIN4
VOUT/RFIN Increased 12dB
VOUTADJ = (VOUT + 0.05)/3.16
VCCA
VCCA
GAIN8
VOUT/RFIN Increased 18dB
VOUTADJ = (VOUT + 0.25)/5.26
Note: Valid range for VOUT ≈ 0.195V ≤ VOUT ≤ VCC – 1.6
LEN
VREF
VP
VCOMP
5564 F02
VOUT
TRANSPARENT
VOUT
LATCHED
VOUT
TRANSPARENT
Figure 2. LTC5564 Comparator Latch Enable Function
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LTC5564
APPLICATIONS INFORMATION
Propagation Delay, Slew Rate and Response Time
Loading, Bypass Capacitors and Board Layout
The LTC5564 has been designed for high slew rate operation. For RF input power levels of 10dBm to 16dBm
and a GAIN1 setting, the internal amplifier will slew at
350V/µs. In a given gain setting slew rate will be maximized
for larger input power levels. Slew rate will degrade with
smaller RFIN amplitude signals or when the amplifier gain
is increased. See Electrical Characteristics.
The LTC5564 has been designed to directly drive a capacitive load of 10pF at VOUT. When driving a capacitive load
greater than 10pF a series resistance should be added
between VOUT and the load to maintain good stability. This
resistance should be placed as close to VOUT as possible.
See Table 2 for typical series resistor values for various
capacitive loads.
The LTC5564 has been designed to function as a positive
peak detector. Consequently, the device responds to a
rising signal at the RF detector input much more rapidly
than a falling signal. Correspondingly, the rising edge of
VOUT transitions much more rapidly than the falling edge
transitions as shown in Figure 3.
Table 2. Typical Series Resistor Values for VOUT
Capacitive Loading
When operating in unity gain with a 10dBm to 16dBm RF
input signal, the propagation delay to fifty percent ∆VOUT
is approximately 7.0ns.
The operational amplifier has been internally compensated
to provide 75MHz bandwidth with VOUT = 500mV and a
GAIN1 mode setting. With no RF input the output offset
will be approximately 290mV. Lowering the output offset
will degrade bandwidth performance. See the Typical
Performance Characteristics.
R SERIES
0Ω
11pF to 20pF
40Ω
21pF to 100pF
68Ω
Greater Than 100pF
100Ω
Good layout practice and proper use of bypass capacitors
will improve circuit performance and reduce the possibility
of measurement error. Bypass capacitors should be used
for pins VCCRF, VCCA, VCCP, VOUTADJ and VREF. Bypass
capacitors should be connected as close to the LTC5564
as possible. All ground return path lengths and ohmic
losses should be minimized. See Figure 5 in the Applications Information section for the demo board schematic
showing these bypass capacitances.
The LTC5564 return path for all supply currents is through
the Pin 17 exposed pad. A high resistance path from the
Pin 17 exposed pad to power supply ground will cause
a VOUT output offset error. Board layout and connections
that minimize ohmic losses from the Pin 17 exposed pad
to power supply ground will reduce this error. Measurements being made relative to LTC5564 ground should be
made as close to the Pin 17 exposed pad to reduce errors.
VOUT
500mV/DIV
ASK MODULATED RF
INPUT SIGNAL START
VCC = 5V
ASK MODULATION FREQUENCY 2.7GHz
GAIN1
10ns/DIV
CLOAD
Up to 10pF
5564 F03
Figure 3. VOUT Pulse Response, PIN = 8dBm
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10
LTC5564
APPLICATIONS INFORMATION
Applications
In addition to power detection, the LTC5564 may be used
as a demodulator for AM and ASK modulated signals.
Depending on the application the RSSI may be split into
two branches to provide AC-coupled data (e.g., audio) and
a DC-coupled RSSI output for signal strength measurement and AGC.
The LTC5564 can be used as a self-standing signal strength
measurement receiver for a wide range of input signals
from –24dBm to 16dBm and frequencies from 600MHz
to 15GHz.
47pF
1
FROM RF MATCHING
NETWORK/ANTENNA
11
15
VCC
1000pF
10pF
12
3, 4, 17
RFIN
VCCP
10
VOUT
VCCRF
VCCA
DETECT
VOLTAGE
LTC5564
GND
8
G1
VCOMP LEN VREF
13
+
5
G0
14
7
µC
DETECT
OVERVOLTAGE
EVENT
5564 F04
Figure 4. 600MHz to 15GHz Power Detector
VCC
1000pF
15GHz
RFIN
10pF
17
2.2pF
0.5pF
1
2
3
4
16
15
14
13
NC VCCRF VREF VCOMP
RFIN
VCCA
NC
VCCP
LTC5564
VOUT
GND
NC
GND
LEN VOUTADJ G0
5
LEN
VREF
100pF
6
VCOMP
VCC
12
10
68Ω
9 100pF
1000pF
VOUT
G1
7
8
10k
10k
G1
G0
VOUTADJ
10k
10pF
11
5564 F05
Figure 5. Demo Board Schematic Optimized for 15GHz
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11
LTC5564
PACKAGE DESCRIPTION
UD Package
16-Lead Plastic QFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1691)
0.70 ±0.05
3.50 ± 0.05
1.45 ± 0.05
2.10 ± 0.05 (4 SIDES)
PACKAGE OUTLINE
0.25 ±0.05
0.50 BSC
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
3.00 ± 0.10
(4 SIDES)
BOTTOM VIEW—EXPOSED PAD
PIN 1 NOTCH R = 0.20 TYP
OR 0.25 × 45° CHAMFER
R = 0.115
TYP
0.75 ± 0.05
15
PIN 1
TOP MARK
(NOTE 6)
16
0.40 ± 0.10
1
1.45 ± 0.10
(4-SIDES)
2
(UD16) QFN 0904
0.200 REF
0.00 – 0.05
NOTE:
1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WEED-2)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON THE TOP AND BOTTOM OF PACKAGE
0.25 ± 0.05
0.50 BSC
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12
LTC5564
REVISION HISTORY
REV
DATE
DESCRIPTION
PAGE NUMBER
A
02/11
Replaced and renamed Typical Application drawing
1
Added new curves to Typical Performance Characteristics
5, 6
Revised Figure 5
11
5564fa
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
13
LTC5564
TYPICAL APPLICATION
600MHz to 15GHz RF Power Detector
33pF
RF INPUT
RFIN
VOUTADJ
VCCA
VOUT
VCCRF
VCC
1000pF
10pF
VCCP
LTC5564
GND
G1
VCOMP LEN VREF
G0
+
µC
5564 TA02
RELATED PARTS
PART NUMBER DESCRIPTION
Schottky Peak Detectors
LTC5505
RF Power Detectors with >40dB Dynamic Range
LTC5507
100kHz to 1000MHz RF Power Detector
LTC5508
300MHz to 7GHz RF Power Detector
LTC5509
300MHz to 3GHz RF Power Detector
LTC5530
300MHz to 7GHz Precision RF Power Detector
LTC5531
300MHz to 7GHz Precision RF Power Detector
LTC5532
300MHz to 7GHz Precision RF Power Detector
LTC5536
Precision 600MHz to 7GHz RF Power Detector
with Fast Comparator Output
RF Log Detectors
LT5534
50MHz to 3GHz Log RF Power Detector with
60dB Dynamic Range
®
LT 5537
Wide Dynamic Range Log RF/IF Detector
LT5538
75dB Dynamic Range 3.8GHz Log RF Power Detector
RMS Detectors
LT5570
60dB Dynamic Range RMS Detector
LTC5581
6GHz RMS Power Detector, 40dB Dynamic Range
LTC5587
10MHz to 6GHz RMS Detector with Digitized Output
LTC5582
10GHz, 57dB Dynamic Range RMS Detector
LTC5583
6GHz, Matched Dual RMS Detector Measures VSWR
COMMENTS
300MHz to 3GHz, Temperature Compensated, 2.7V to 6V Supply
100kHz to 1GHz, Temperature Compensated, 2.7V to 6V Supply
44dB Dynamic Range, Temperature Compensated, SC70 Package
36dB Dynamic Range, Low Power Consumption, SC70 Package
Precision VOUT Offset Control, Shutdown, Adjustable Gain
Precision VOUT Offset Control, Shutdown, Adjustable Offset
Precision VOUT Offset Control, Adjustable Gain and Offset
25ns Response Time, Comparator Reference Input, Latch Enable Input,
–26dBm to +12dBm Input Range
±1dB Output Variation Over Temperature, 38ns Response Time,
Log Linear Response
Low Frequency to 1GHz, 83dB Log Linear Dynamic Range
±0.8dB Accuracy Over Temperature
40MHz to 2.7GHz, ±0.5dB Accuracy Over Temperature
±1dB Accuracy Over Temperature, Log Linear Response, 1.4mA at 3.3V
40dB Dynamic Detection Range, Integrated 12-Bit Serial Output ADC,
±1dB Accuracy Over Temperature
40MHz to 10GHz Operation, ±0.5dB Linearity Single-Ended RF Output—
Requires No External Balun Transformer
Up to 60dB Dynamic Range, ±0.5dB Accuracy Over Temperature,
40dB Channel-to-Channel Isolation with Single-Ended RF Inputs
5564fa
14 Linear Technology Corporation
LT 0311 REV A • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2010
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