LINER LT5520 1.3ghz to 2.3ghz high linearity upconverting mixer Datasheet

LT5520
1.3GHz to 2.3GHz
High Linearity
Upconverting Mixer
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FEATURES
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DESCRIPTIO
Wide RF Output Frequency Range: 1.3GHz
to 2.3GHz
15.9dBm Typical Input IP3 at 1.9GHz
On-Chip RF Output Transformer
No External LO or RF Matching Required
Single-Ended LO and RF Operation
Integrated LO Buffer: –5dBm Drive Level
Low LO to RF Leakage: – 41dBm Typical
Wide IF Frequency Range: DC to 400MHz
Enable Function with Low Off-State Leakage Current
Single 5V Supply
Small 16-Lead QFN Plastic Package
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APPLICATIO S
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Wireless Infrastructure
Cable Downlink Infrastructure
Point-to-Point Data Communications
High Linearity Frequency Conversion
The LT®5520 mixer is designed to meet the high linearity
requirements of wireless and cable infrastructure transmission applications. A high-speed, internally matched,
LO amplifier drives a double-balanced mixer core, allowing the use of a low power, single-ended LO source. An RF
output transformer is integrated, thus eliminating the
need for external matching components at the RF output,
while reducing system cost, component count, board area
and system-level variations. The IF port can be easily
matched to a broad range of frequencies for use in many
different applications.
The LT5520 mixer delivers 15.9dBm typical input 3rd
order intercept point at 1.9GHz with IF input signal levels
of –10dBm. The input 1dB compression point is typically
4dBm. The IC requires only a single 5V supply.
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATIO
5VDC
1µF
RF Output Power and Output IM3 vs
IF Input Power (Two Input Tones)
1000pF
39nH
10
BPF
IF
INPUT
220pF
VCC1
VCC2
VCC3
BIAS
100Ω
0
–10
10pF
4:1
IF +
RF +
IF –
RF –
15pF
220pF
PA
BPF
100Ω
RF
OUTPUT
POUT, IM3 (dBm/TONE)
EN
–20
–30
–40
–50
–60
–70
–80
GND
5pF
(OPTIONAL)
LO INPUT
–5dBm
LO+
85Ω
5pF
LO –
POUT
–90
–16
LT5520
IM3
PLO = –5dBm
fLO = 1760MHz
fIF1 = 140MHz
fIF2 = 141MHz
fRF = 1900MHz
TA = 25°C
–12
–4
0
–8
IF INPUT POWER (dBm/TONE)
4
5520 • F01b
5520 F01
Figure 1. Frequency Conversion in Wireless Infrastructure Transmitter
5520f
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LT5520
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PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
GND
TOP VIEW
16 15 14 13
LT5520EUF
12 GND
GND 1
IF + 2
11 RF +
17
IF – 3
10 RF –
9 GND
5
6
7
8
EN
VCC2
VCC3
GND 4
VCC1
Supply Voltage ....................................................... 5.5V
Enable Voltage ............................. –0.3V to (VCC + 0.3V)
LO Input Power (Differential) .............................. 10dBm
RF+ to RF – Differential DC Voltage...................... ±0.13V
RF Output DC Common Mode Voltage ......... –1V to VCC
IF Input Power (Differential) ............................... 10dBm
IF+, IF – DC Currents .............................................. 25mA
LO+ to LO– Differential DC Voltage .......................... ±1V
LO Input DC Common Mode Voltage ............ –1V to VCC
Operating Temperature Range .................–40°C to 85°C
Storage Temperature Range ................. – 65°C to 125°C
Junction Temperature (TJ).................................... 125°C
GND
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(Note 1)
LO+
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AXI U RATI GS
LO–
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ABSOLUTE
UF PART
MARKING
UF PACKAGE
16-LEAD (4mm × 4mm) PLASTIC QFN
EXPOSED PAD IS GND (PIN 17),
MUST BE SOLDERED TO PCB
5520
TJMAX = 125°C, θJA = 37°C/W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
PARAMETER
CONDITIONS
MIN
IF Input Frequency Range
TYP
MAX
UNITS
DC to 400
MHz
LO Input Frequency Range
900 to 2700
MHz
RF Output Frequency Range
1300 to 2300
MHz
1900MHz Application: VCC = 5VDC, EN = High, TA = 25°C, IF input = 140MHz at –10dBm, LO input = 1.76GHz at –5dBm, RF output
measured at 1900MHz, unless otherwise noted. Test circuit shown in Figure 2. (Notes 2, 3)
PARAMETER
CONDITIONS
MIN
IF Input Return Loss
ZO = 50Ω, with External Matching
20
dB
LO Input Return Loss
ZO = 50Ω
16
dB
RF Output Return Loss
ZO = 50Ω
20
dB
LO Input Power
TYP
MAX
–10 to 0
Conversion Gain
dBm
–1
Input 3rd Order Intercept
–10dBm/Tone, ∆f = 1MHz
Input 2nd Order Intercept
–10dBm, Single-Tone
UNITS
dB
15.9
dBm
45
dBm
LO to RF Leakage
–41
dBm
LO to IF Leakage
–35
dBm
4
dBm
Input 1dB Compression
IF Common Mode Voltage
Internally Biased
1.77
VDC
Noise Figure
Single Side Band
15
dB
DC ELECTRICAL CHARACTERISTICS
(Test Circuit Shown in Figure 2) VCC = 5VDC, EN = High , TA = 25°C (Note 3), unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Enable (EN) Low = Off, High = On
Turn-On Time (Note 4)
Turn-Off Time (Note 4)
Input Current
µs
2
µs
6
VENABLE = 5VDC
1
10
µA
5520f
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LT5520
DC ELECTRICAL CHARACTERISTICS
(Test Circuit Shown in Figure 2) VCC = 5VDC, EN = High , TA = 25°C (Note 3), unless otherwise noted.
PARAMETER
CONDITIONS
MIN
Enable = High (On)
TYP
MAX
UNITS
3
VDC
Enable = Low (Off)
0.5
VDC
Power Supply Requirements (VCC)
Supply Voltage
4.5 to 5.25
VDC
Supply Current
VCC = 5VDC
60
70
mA
Shutdown Current
EN = Low
1
100
µA
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: External components on the final test circuit are optimized for
operation at fRF = 1900MHz, fLO = 1.76GHz and fIF = 140MHz.
Note 3: Specifications over the –40°C to 85°C temperature range are
assured by design, characterization and correlation with statistical process
controls.
Note 4: Turn-On and Turn-Off times are based on the rise and fall times of
the RF output envelope from full power to –40dBm with an IF input power
of –10dBm.
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TYPICAL PERFOR A CE CHARACTERISTICS
Shutdown Current
vs Supply Voltage
Supply Current
vs Supply Voltage
1.0
66
0.9
TA = 85°C
SHUTDOWN CURRENT (µA)
SUPPLY CURRENT (mA)
64
62
TA = 25°C
60
58
TA = –40°C
56
54
52
50
4.0
(Test Circuit Shown in Figure 2)
0.8
0.7
0.6
TA = 85°C
0.5
0.4
0.3
0.2
TA = 25°C
TA = –40°C
0.1
4.25
4.5
4.75
5.0
SUPPLY VOLTAGE (V)
5.25
0
4.0
5.5
4.25
5.25
4.5
4.75
5.0
SUPPLY VOLTAGE (V)
5.5
5520 • GO2
5520 • GO1
VCC = 5VDC, EN = High, TA = 25°C, IF input = 140MHz at –10dBm, LO input = 1.76GHz at –5dBm, RF output measured at 1900MHz,
unless otherwise noted. For 2-tone inputs: 2nd IF input = 141MHz at –10dBm. (Test Circuit Shown in Figure 2.)
18
32
16 HIGH SIDE LO
SSB NF
IIP3 (dBm)
6
4
22
30
20
25
IIP3
20
LOW SIDE LO
15
HIGH SIDE LO
1500 1700 1900 2100 2300 2500
RF OUTPUT FREQUENCY (MHz)
5520 • GO3
–20
12
1300
–30
HIGH SIDE LO
–40
–50
LOW SIDE LO
10
14
–2
45
35
HIGH SIDE LO
24
16
LOW SIDE AND HIGH SIDE LO
–10
40
18
2
–4
1300
IIP2
26
8
0
LOW SIDE LO
28
10
GAIN
55
IIP2 (dBm)
GAIN, NF (dB)
12
LO-RF Leakage
vs RF Output Frequency
50
30
LOW SIDE LO
14
IIP3 and IIP2
vs RF Output Frequency
LO LEAKAGE (dBm)
Conversion Gain and SSB Noise
Figure vs RF Output Frequency
1500 1700 1900 2100 2300
RF OUTPUT FREQUENCY (MHz)
5
2500
5520 • GO4
–60
1300
1500 1700 1900 2100 2300
RF OUTPUT FREQUENCY (MHz)
2500
5520 • GO5
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LT5520
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TYPICAL PERFOR A CE CHARACTERISTICS
VCC = 5VDC, EN = High , TA = 25°C, IF input = 140MHz at –10dBm, LO input = 1.76GHz at –5dBm, RF output measured at 1900MHz,
unless otherwise noted. For 2-tone inputs: 2nd IF Input = 141MHz at –10dBm. (Test Circuit Shown in Figure 2.)
Conversion Gain and SSB Noise
Figure vs LO Input Power
50
18
45
16
40
14
35
TA = 85°C
SSB NF
10
GAIN (dB)
TA = –40°C
TA = 25°C
12
6
10
4
8
2
GAIN
TA = 25°C
6
TA = –40°C
0
–2
–4
–16
TA = 85°C
–12
–8
–4
0
LO INPUT POWER (dBm)
NF (dB)
8
–10
TA = 25°C
TA = 85°C
IIP2
30
25
20
IIP3
TA = 25°C, TA = –40°C
15
–30
TA = –40°C
–40
10
2
5
0
0
–16
–50
0
–8
–12
–4
LO INPUT POWER (dBm)
5520 • G06
–60
–16
4
RF Output Power and Output IM2 vs
IF Input Power (Two Input Tones)
10
10
40
–10
HIGH SIDE LO
30
25
IIP3
HIGH SIDE LO
15
LOW SIDE LO
–20
–30
0
TA = –40°C
TA = 85°C
TA = 25°C
POUT, IM2 (dBm/TONE)
0
POUT, IM3 (dBm/TONE)
IIP3, IIP2 (dBm)
LOW SIDE LO
45
20
POUT
–40
–50
–60
TA = –40°C
TA = 85°C
IM3
IM2
–70
0
–8
–12
–4
IF INPUT POWER (dBm/TONE)
–80
–16
4
–5
RETURN LOSS (dB)
–3
–10
–15
LO PORT
IF PORT
RF PORT
4
5520 • G12
0
500
1000 1500 2000
FREQUENCY (MHz)
25
3
IIP3
2
HIGH SIDE LO
3000
5520 • G13
20
15
LOW SIDE LO
10
GAIN
–1
2500
35
30
1
–25
0
–8
–4
IF INPUT POWER (dBm)
40
IIP2
4
0
–5
–12
HIGH SIDE LO
5
–20
–4
45
IIP3, IIP2 (dBm)
TA = 85°C
–2
6
GAIN (dB)
2
–6
–16
50
LOW SIDE LO
7
–1
4
8
3
TA = 25°C
0
–8
–12
–4
IF INPUT POWER (dBm/TONE)
Conversion Gain, IIP3 and IIP2
vs Supply Voltage
0
4
0
TA = 25°C
5520 • G11
IF, LO and RF Port Return Loss
vs Frequency
TA = –40°C
TA = 85°C
5520 • G10
Conversion Gain vs IF Input
Power (One Input Tone)
1
TA = –40°C
–50
–80
–90
–16
POUT
–40
5
4
TA = 25°C
–30
–60
5520 • G09
GAIN (dB)
TA = 85°C
–20
–70
0
–8
–12
–4
LO INPUT POWER (dBm)
TA = –40°C
–10
10
0
–16
4
5520 • G08
RF Output Power and Output IM3 vs
IF Input Power (Two Input Tones)
50
35
0
–8
–12
–4
LO INPUT POWER (dBm)
5520 • G07
IIP3 and IIP2 vs
LO Input Power
IIP2
TA = 85°C
TA = 25°C
TA = 85°C
4
4
–20
TA = –40°C
LO LEAKAGE (dBm)
20
14
IIP3, IIP2 (dBm)
16
12
LO-RF Leakage
vs LO Input Power
IIP3 and IIP2 vs
LO Input Power
–2
4.0
5
LOW SIDE AND HIGH SIDE LO
4.25
5.25
4.5
4.75
5.0
SUPPLY VOLTAGE (V)
0
5.5
5520 • G14
5520f
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LT5520
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PI FU CTIO S
GND (Pins 1, 4, 9, 12, 13, 16): Internal Grounds. These
pins are used to improve isolation and are not intended as
DC or RF grounds for the IC. Connect these pins to low
impedance grounds for best performance.
IF+, IF – (Pins 2, 3): Differential IF Signal Inputs. A differential signal must be applied to these pins through DC
blocking capacitors. The pins must be connected to ground
with 100Ω resistors (the grounds must each be capable of
sinking about 18mA). For best LO leakage performance,
these pins should be DC isolated from each other. An
impedance transformation is required to match the IF
input to the desired source impedance (typically 50Ω or
75Ω).
EN (Pin 5): Enable Pin. When the applied voltage is greater
than 3V, the IC is enabled. When the applied voltage is less
than 0.5V, the IC is disabled and the DC current drops to
about 1µA.
VCC1 (Pin 6): Power Supply Pin for the Bias Circuits.
Typical current consumption is about 2mA. This pin
should be externally connected to VCC and have appropriate RF bypass capacitors.
VCC2 (Pin 7): Power Supply Pin for the LO Buffer Circuits.
Typical current consumption is about 22mA. This pin
should have appropriate RF bypass capacitors as shown
in Figure 2. The 1000pF capacitor should be located as
close to the pins as possible.
VCC3 (Pin 8): Power Supply Pin for the Internal Mixer.
Typical current consumption is about 36mA. This pin
should be externally connected to VCC through an inductor. A 39nH inductor is used in Figure 2, though the value
is not critical.
RF –, RF+ (Pins 10, 11): Differential RF Outputs. One pin
may be DC connected to a low impedance ground to realize
a 50Ω single-ended output. No external matching components are required. A DC voltage should not be applied
across these pins, as they are internally connected through
a transformer winding.
LO+, LO – (Pins 14, 15): Differential Local Oscillator Inputs. The LT5520 works well with a single-ended source
driving the LO+ pin and the LO– pin connected to a low
impedance ground. No external matching components are
required. An internal resistor is connected across these
pins; therefore, a DC voltage should not be applied across
the inputs.
GROUND (Pin 17, Exposed Pad): DC and RF ground
return for the entire IC. This must be soldered to the
printed circuit board low impedance ground plane.
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BLOCK DIAGRA
BACKSIDE
GROUND GND
17
12
RF +
11
RF –
10
GND
9
GND 13
5pF
8 VCC3
HIGH SPEED
LO BUFFER
LO+ 14
10pF
DOUBLEBALANCED
MIXER
85Ω
LO – 15
6 VCC1
5pF
BIAS
GND 16
5 EN
7
1
2
3
4
VCC2
GND
IF +
IF –
GND
5520 BD
5520f
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LT5520
TEST CIRCUIT
LOIN
1760MHz
16
1 GND
GND
IFIN
140MHz
1
14
LO+
13
GND 12
GND
R1
C1
T1
2
5
2
IF +
4
3
C2
ER = 4.4
R2
RF
GND
0.018"
4
IF –
GND
EN
5
DC
GND
11
RF –
10
VCC1
VCC2
6
7
GND
VCC3
EN
0.062"
RF +
REF DES
VALUE
SIZE
PART NUMBER
C1, C2
220pF
0402
AVX 04023C221KAT2A
C3
15pF
0402
AVX 04023A150KAT2A
C4
1000pF
0402
AVX 04023A102KAT2A
C5
1µF
0603
Taiyo Yuden LMK107BJ105MA
L1
39nH
0402
Toko LL1005-FH39NJ
LT5520
C3
3
0.018"
15
LO –
RFOUT
1900MHz
9
R1, R2
8
L1
100Ω, 0.1%
0603
4:1
SM-22
T1
IRC PFC-W0603R-03-10R1-B
M/A-COM ETC4-1-2
VCC
C5
C4
5520 TC01
Figure 2. Test Schematic for the LT5520
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APPLICATIO S I FOR ATIO
The LT5520 consists of a double-balanced mixer, a highperformance LO buffer, and bias/enable circuits. The RF
and LO ports may be driven differentially; however, they
are intended to be used in single-ended mode by connecting one input of each pair to ground. The IF input ports
must be DC-isolated from the source and driven differentially. The IF input should be impedance-matched for the
desired input frequency. The LO input has an internal
broadband 50Ω match with return loss better than 10dB
at frequencies up to 3000MHz. The RF output band ranges
from 1300MHz to 2300MHz, with an internal RF transformer providing a 50Ω impedance match across the
band. Low side or high side LO injection can be used.
IF Input Port
The IF inputs are connected to the emitters of the doublebalanced mixer transistors, as shown in Figure 3. These
pins are internally biased and an external resistor must be
connected from each IF pin to ground to set the current
through the mixer core. The circuit has been optimized to
work with 100Ω resistors, which will result in approximately 18mA of DC current per side. For best LO leakage
performance, the resistors should be well matched; thus
resistors with 0.1%, tolerance are recommended. If LO
leakage is not a concern, then lesser tolerance resistors
can be used. The symmetry of the layout is also important
for achieving optimum LO isolation.
The capacitors shown in Figure 3, C1 and C2, serve two
purposes. They provide DC isolation between the IF+ and
IF – ports, thus preventing DC interactions that could
cause unpredictable variations in LO leakage. They also
improve the impedance match by canceling excess inductance in the package and transformer. The input capacitor
value required to realize an impedance match at desired
frequency, f, can be estimated as follows:
C1 = C2 =
1
(2πf)2 (LIN + LEXT )
where; f is in units of Hz, LIN and LEXT are in H, and C1, C2
are in farad. LIN is the differential input inductance of the
LT5520, and is approximately 1.67nH. LEXT represents the
combined inductances of differential external components and transmission lines. For the evaluation board
shown in Figure 10, LEXT = 4.21nH. Thus, for f = 140MHz,
the above formula gives C1 = C2 = 220pF.
5520f
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LT5520
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APPLICATIO S I FOR ATIO
100Ω
0.1%
C1
T1
4:1
IFIN
50Ω
LOIN
50Ω
18mA
14
5pF
LO+
220Ω
2
C3
VCC
VCC
3
C2
100Ω
0.1%
18mA
15
LT5520
85Ω
5pF
LO –
220Ω
LT5520
5520 F03
5520 F04
Figure 3. IF Input with External Matching
Figure 4. LO Input Circuit
Table 1 lists the differential IF input impedance and reflection coefficient for several frequencies. A 4:1 balun can be
used to transform the impedance up to about 50Ω.
Differential S11
Mag
Angle
Though the LO input is internally 50Ω matched, there may
be some cases, particularly at higher frequencies or with
different source impedances, where a further optimized
match is desired. Table 2 includes the single -ended input
impedance and reflection coefficient vs frequency for the
LO input for use in such cases.
Table 2. Single-Ended LO Input Impedance
Table 1. IF Input Differential Impedance
Frequency
(MHz)
Differential Input
Impedance
10
10.1 + j0.117
0.663
180
44
10.1 + j0.476
0.663
179
70
10.1 + j0.751
0.663
178
Frequency
(MHz)
Input
Impedance
Mag
Angle
140
10.2 + j1.47
0.663
177
1300
62.8 – j9.14
0.139
–30.9
170
10.2 + j1.78
0.663
176
1500
62.2 – j11.4
0.148
–37.1
240
10.2 + j2.53
0.663
174
1700
61.5 – j13.4
0.157
– 42.4
360
10.2 + j3.81
0.663
171
1900
60.0 – j15.2
0.164
– 48.9
500
10.2 + j5.31
0.663
167
2100
58.4 – j16.9
0.172
–54.7
2300
56.5 – j17.9
0.176
–60.4
2500
54.9 – j18.8
0.182
–65.1
2700
53.7 – j18.8
0.182
–68.5
LO Input Port
The simplified circuit for the LO buffer input is shown in
Figure 4. The LO buffer amplifier consists of high-speed
limiting differential amplifiers, optimized to drive the mixer
quad for high linearity. The LO + and LO – ports can be
driven differentially; however, they are intended to be
driven by a single-ended source. An internal resistor
connected across the LO + and LO – inputs provides a
broadband 50Ω impedance match. Because of the resistive match, a DC voltage at the LO input is not recommended. If the LO signal source output is not AC coupled,
then a DC blocking capacitor should be used at the LO
input.
S11
RF Output Port
An internal RF transformer, shown in Figure 5, reduces the
mixer-core impedance to provide an impedance of 50Ω
across the RF + and RF – pins. The LT5520 is designed and
tested with the outputs configured for single-ended operation, as shown in the Figure 5; however, the outputs can be
used differentially as well. A center-tap in the transformer
provides the DC connection to the mixer core and the
transformer provides DC isolation at the RF output. The
RF + and RF – pins are connected together through the
secondary windings of the transformer, thus a DC voltage
should not be applied across these pins.
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LT5520
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APPLICATIO S I FOR ATIO
The impedance data for the RF output, listed in Table 3, can
be used to develop matching networks for different load
impedances.
Table 3. Single-Ended RF Output Impedance
Frequency
(MHz)
Input
Impedance
Mag
Angle
1300
26.9 + j38.2
0.520
94.7
1500
44.2 + j35.7
0.359
78.4
1700
53.9 + j20.6
0.198
68.0
3
1900
49.5 + j7.97
0.080
88.9
2
14
2100
42.8 + j4.14
0.089
148
1
12
2300
38.9 + j5.41
0.139
151
2700
41.1 – j9.51
0.154
140
0.142
20
4
GAIN (dB)
38.7 + j7.78
5
18
LOW SIDE LO
IIP3
16
HIGH SIDE LO
0 GAIN
10
–1
8
LOW SIDE LO
–2
127
6
HIGH SIDE LO
–3
4
–4
2
–5
RF+
0
11
IIP3 (dBm)
2500
S11
The performance was evaluated with the input tuned for
each of these frequencies and the results are summarized
in Figures 6-8. The same IF input balun transformer was
used for all measurements. In each case, the LO input
frequency was adjusted to maintain an RF output frequency of 1900 MHz.
100
0
700
200 300 400 500 600
INPUT FREQUENCY (MHz)
5520 F06
Figure 6. Conversion Gain and IIP3
vs Tuned IF Input Frequency
VCC
RF–
LT5520
18
RFOUT
50Ω
PLO = –5dBm
5520 F05
Figure 5. RF Output Circuit
Operation at Different Input Frequencies
On the evaluation board shown in Figure 10, the input of
the LT5520 can be easily matched for different frequencies
by changing the input capacitors, C1 and C2. Table 4 lists
some actual values used at selected frequencies.
Table 4. Input Capacitor Values vs Frequency
17
NF (dB)
8
VCC
10
HIGH SIDE LO
16
15
LOW SIDE LO
PLO = 0dBm
14
13
0
100
200 300 400 500 600
INPUT FREQUENCY (MHz)
700
5520 F07
Frequency
(MHz)
Capacitance (C1, C2)
(pF)
70
820
140
220
240
68
480
18
650
12
Figure 7. SSB Noise Figure vs Tuned IF Input Frequency
5520f
8
LT5520
U
W
U
U
APPLICATIO S I FOR ATIO
Figures 6-8 illustrate the performance versus tuned IF
input frequency with both high side and low side LO
injection. Figure 6 shows the measured conversion gain
and IIP3. The noise figure is plotted in Figure 7 for LO
power levels of –5dBm and 0dBm. At lower input frequencies, the LO power level has little impact on noise figure.
However, for higher frequencies, an increased LO drive
level may be utilized to achieve better noise figure. The
single-tone IIP2 behavior is illustrated in Figure 8.
Low Frequency Matching of the RF Output Port
Without any external components on the RF output, the
internal transformer of the LT5520 provides a good 50Ω
impedance match for RF frequencies above approximately
1600MHz. At frequencies lower than this, the return loss
drops below 10dB and degrades the conversion gain. The
addition of a single 3.3pF capacitor in series with the RF
output improves the match at lower RF frequencies,
shifting the 10dB return loss point to about 1300MHz, as
demonstrated in Figure 9. This change also results in an
improvement of the conversion gain, as shown in
Figure 9.
60
0
LOW SIDE LO
50
–1
GAIN (dB)
IIP2 (dBm)
HIGH SIDE LO
30
20
COUT = 3.3pF
NO COUT
–5
GAIN
–10
–3
–4
RETURN LOSS
–15
–5
–6
–20
–7
10
–8
0
100
200 300 400 500 600
INPUT FREQUENCY (MHz)
700
5520 F08
Figure 8. IIP2 vs Tuned IF Input Frequency
COUT = 3.3pF
–9
1200 1400 1600 1800 2000
FREQUENCY (MHz)
RETURN LOSS (dB)
–2
40
0
0
1
NO COUT
2200
–25
2400
5520 F09
Figure 9. Conversion Gain and Return Loss vs Output Frequency
5520f
9
LT5520
U
W
U
U
APPLICATIO S I FOR ATIO
(10a) Top Layer Silkscreen
(10b) Top Layer Metal
Figure 10. Evaluation Board Layout
5520f
10
LT5520
U
PACKAGE DESCRIPTIO
UF Package
16-Lead Plastic QFN (4mm × 4mm)
(Reference LTC DWG # 05-08-1692)
BOTTOM VIEW—EXPOSED PAD
4.00 ± 0.10
(4 SIDES)
0.72 ±0.05
0.75 ± 0.05
R = 0.115
TYP
0.55 ± 0.20
15
16
PIN 1
TOP MARK
1
4.35 ± 0.05
2.15 ± 0.05
2.90 ± 0.05 (4 SIDES)
2.15 ± 0.10
(4-SIDES)
PACKAGE
OUTLINE
0.30 ±0.05
0.65 BCS
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
2
(UF) QFN 0802
0.200 REF
0.00 – 0.05
0.30 ± 0.05
0.65 BSC
NOTE:
1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WGGC)
2. ALL DIMENSIONS ARE IN MILLIMETERS
3. 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
4. EXPOSED PAD SHALL BE SOLDER PLATED
5520f
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.
11
LT5520
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
Infrastructure
LT5511
High Signal Level Upconverting Mixer
RF Output to 3GHz, 17dBm IIP3, Integrated LO Buffer
LT5512
DC-3GHz High Signal Level Downconverting Mixer
RF Input to 3GHz, 20dBm IIP3, Integrated LO Buffer
LT5515
1.5GHz to 2.5GHz Direct Conversion Quadrature Demodulator 20dBm IIP3,Integrated LO Quadrature Generator
LT5516
0.8GHz to 1.5GHz Direct Conversion Quadrature Demodulator 21.5dBm IIP3,Integrated LO Quadrature Generator
LT5522
600MHz to 2.7GHz High Signal Level Downconverting Mixer
4.5V to 5.25V Supply, 25dBm IIP3 at 900MHz, NF = 12.5dB,
50Ω Single-Ended RF and LO Ports
LT5504
800MHz to 2.7GHz RF Measuring Receiver
80dB Dynamic Range, Temperature Compensated, 2.7V to 6V Supply
LTC5505
RF Power Detectors with >40dB Dynamic Range
300MHz to 3GHz, Temperature Compensated, 2.7V to 5.5V Supply
LTC5507
100kHz to 1000MHz RF Power Detector
300MHz to 3GHz, Temperature Compensated, 2.7V to 5.5V Supply
LTC5508
300MHz to 7GHz RF Power Detector
44dB Dynamic Range, Temperature Compensated, SC70 Package
LTC5509
300MHz to 3GHz RF Power Detector
36dB Dynamic Range, Temperature Compensated, SC70 Package
LTC5532
300MHz to 7GHz Precision RF Power Detector
Precision VOUT Offset Control, Adjustable Gain and Offset
RF Power Detectors
RF Receiver Building Blocks
LT5500
1.8GHz to 2.7GHz Receiver Front End
1.8V to 5.25V Supply, Dual-Gain LNA, Mixer LO Buffer
LT5502
400MHz Quadrature IF Demodulator with RSSI
1.8V to 5.25V Supply, 70MHz to 400MHz IF, 84dB Limiting Gain,
90dB RSSI Range
LT5503
1.2GHz to 2.7GHz Direct IQ Modulator and
Upconverting Mixer
1.8V to 5.25V Supply, Four-Step RF Power Control,
120MHz Modulation Bandwidth
LT5506
500MHz Quadrature IF Demodulator with VGA
1.8V to 5.25V Supply, 40MHz to 500MHz IF, –4dB to 57dB
Linear Power Gain, 8.8MHz Baseband Bandwidth
LT5546
500MHz Ouadrature IF Demodulator with
VGA and 17MHz Baseband Bandwidth
1.8V to 5.25V Supply, 40MHz to 500MHz IF,
–7dB to 56dB Linear Power Gain
5520f
12
Linear Technology Corporation
LT/TP 1103 1K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2003