LT5557
1
5557fc
Typical applicaTion
DescripTion
400MHz to 3.8GHz 3.3V
Active Downconverting Mixer
The LT
®
5557 active mixer is optimized for high linearity,
wide dynamic range downconverter applications. The
IC includes a high speed differential LO buffer amplifier
driving a double-balanced mixer. Broadband, integrated
transformers on the RF and LO inputs provide single-ended
50Ω interfaces. The differential IF output allows convenient
interfacing to differential IF filters and amplifiers, or is
easily matched to drive a single-ended 50Ω load, with or
without an external transformer.
The RF input is internally matched to 50Ω from 1.6GHz
to 2.3GHz, and the LO input is internally matched to 50Ω
from 1GHz to 5GHz. The frequency range of both ports
is easily extended with simple external matching. The IF
output is partially matched and usable for IF frequencies
up to 600MHz.
The LT5557’s high level of integration minimizes the total
solution cost, board space and system-level variation.
High Signal Level Downmixer for Multi-Carrier Wireless Infrastructure
FeaTures
applicaTions
n Wide RF Frequency Range: 400MHz to 3.8GHz*
n High Input IP3: 25.6dBm at 900MHz
24.7dBm at 1950MHz
23.7dBm at 2.6GHz
n Conversion Gain: 3.3dB at 900MHz
2.9dB at 1950MHz
n –3dBm LO Drive Level
n Low LO Leakage
n
Low Noise Figure: 10.6dB at 900MHz
11.7dB at 1950MHz
n Low Power: 3.3V/269mW
n 50Ω Single-Ended RF and LO Ports
n Very Few External Components
n 16-Lead (4mm × 4mm) QFN Package
n Cellular, CDMA, WCDMA, TD-SCDMA and UMTS
Infrastructure
n WiMAX
n Wireless Infrastructure Receiver
n Wireless Infrastructure PA Linearization
n 900MHz/2.4GHz/3.5GHz WLAN
Conversion Gain, IIP3, SSB NF and
LO Leakage vs RF Frequency
BIAS
EN
RF
IF+
IF–
100nH
100nH
4.7pF
150nH
IF
OUTPUT
240MHz
RF
INPUT
VCC2 VCC1
LO INPUT
–3dBm (TYP)
1nF 1µF
1nF
4.7pF
3.3V
5557 TA01a
LT5557
GND
RF FREQUENCY (MHz)
1700
GC (dB), NF (dB), IIP3 (dBm)
LO LEAKAGE (dBm)
10
22
24
26
1900 2100
5557 TA01b
6
18
14
8
20
2
4
16
12
40
20
10
0
30
60
50
1800 2000 2200
LOW SIDE LO
IF = 240MHz
PLO = –3dBm
TA = 25°C
VCC = 3.3V
IIP3
SSB NF
GC
LO-IF
LO-RF
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective
owners.\*Operation over a wider frequency range is possible with reduced performance.
Consult factory for information and assistance.
LT5557
2
5557fc
absoluTe MaxiMuM raTings
Supply Voltage (VCC1, VCC2, IF+, IF–) ..........................4V
Enable Voltage .................................–0.3V to VCC + 0.3V
LO Input Power (380MHz to 4.2GHz) ................. +10dBm
LO Input DC Voltage ............................... –1V to VCC + 1V
RF Input Power (400MHz to 3.8GHz) ................. +15dBm
Continuous RF Input Power
(400MHz to 3.8GHz) .......................................... +12dBm
RF Input DC Voltage ............................................... ±0.1V
Operating Temperature Range .................–40°C to 85°C
Storage Temperature Range .................. –65°C to 125°C
Junction Temperature (TJ) .................................... 125°C
(Note 1)
Dc elecTrical characTerisTics
PARAMETER CONDITIONS MIN TYP MAX UNITS
Power Supply Requirements (VCC)
Supply Voltage 2.9 3.3 3.9 V
Supply Current VCC1 (Pin 7)
VCC2 (Pin 6)
IF+ + IF– (Pin 11 + Pin 10)
Total Supply Current
25.1
3.3
53.2
81.6
60
92
mA
mA
mA
mA
Enable (EN) Low = Off, High = On
Shutdown Current EN = Low 100 µA
Input High Voltage (On) 2.7 V
Input Low Voltage (Off) 0.3 V
EN Pin Input Current EN = 3.3V DC 53 90 µA
Turn-ON Time 1.6 µs
Turn-OFF Time 1.6 µs
VCC = 3.3V, EN = High, TA = 25°C, unless otherwise specified. Test
circuit shown in Figure 1. (Note 3)
ac elecTrical characTerisTics
Test circuit shown in Figure 1. (Notes 2, 3)
PARAMETER CONDITIONS MIN TYP MAX UNITS
RF Input Frequency Range No External Matching (Midband)
With External Matching (Low Band or High Band)
400 1600 to 2300
3800 MHz
MHz
LO Input Frequency Range No External Matching
With External Matching
380 1000 to 4200 MHz
MHz
IF Output Frequency Range Requires Appropriate IF Matching 0.1 to 600 MHz
RF Input Return Loss ZO = 50Ω, 1600MHz to 2300MHz (No External Matching) >12 dB
pin conFiguraTion
16 15 14 13
5 6 7 8
TOP VIEW
17
UF PACKAGE
16-LEAD (4mm × 4mm) PLASTIC QFN
9
10
11
12
4
3
2
1NC
NC
RF
NC
GND
IF+
IF–
GND
NC
LO
NC
NC
EN
VCC2
VCC1
NC
TJMAX = 125°C, θJC = 8°C/W, θJA = 37°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
CAUTION: This part is sensitive to electrostatic discharge
(ESD). It is very important that proper ESD precautions
be observed when handling the LT5557.
LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE
LT5557EUF#PBF LT5557EUF#TRPBF 5557 16-Lead (4mm × 4mm) 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/
orDer inForMaTion
LT5557
3
5557fc
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: 450MHz and 900MHz performance measured with external LO
and RF matching. 2600MHz and 3600MHz performance measured with
external RF matching. See Figure 1 and Applications Information.
Standard Downmixer Application: VCC = 3.3V, EN = High, TA = 25°C, PRF = –6dBm (–6dBm/tone for 2-tone IIP3 tests, ∆f = 1MHz), fLO
= fRF – fIF, PLO = –3dBm (0dBm for 450MHz and 900MHz tests), IF output measured at 240MHz, unless otherwise noted. Test circuit
shown in Figure 1. (Notes 2, 3, 4)
PARAMETER CONDITIONS MIN TYP MAX UNITS
Conversion Gain RF = 450MHz, IF = 70MHz, High Side LO
RF = 900MHz, IF = 140MHz
RF = 1750MHz
RF = 1950MHz
RF = 2150MHz
RF = 2600MHz, IF = 360MHz
RF = 3600MHz, IF = 450MHz
2.9
3.3
3.0
2.9
2.9
2.5
1.7
dB
dB
dB
dB
dB
dB
dB
Conversion Gain vs Temperature TA = –40°C to 85°C, RF = 1950MHz –0.0217 dB/°C
Input 3rd Order Intercept RF = 450MHz, IF = 70MHz, High Side LO
RF = 900MHz, IF = 140MHz
RF = 1750MHz
RF = 1950MHz
RF = 2150MHz
RF = 2600MHz, IF = 360MHz
RF = 3600MHz, IF = 450MHz
24.1
25.6
25.5
24.7
24.3
23.7
23.5
dBm
dBm
dBm
dBm
dBm
dBm
dBm
Single-Sideband Noise Figure RF = 450MHz, IF = 70MHz, High Side LO
RF = 900MHz, IF = 140MHz
RF = 1750MHz
RF = 1950MHz
RF = 2150MHz
RF = 2600MHz, IF = 360MHz
RF = 3600MHz, IF = 450MHz
12.7
10.6
11.3
11.7
12.8
13.2
15.4
dB
dB
dB
dB
dB
dB
dB
LO to RF Leakage fLO = 380MHz to 1600MHz
fLO = 1600MHz to 4000MHz
≤–50
≤–45
dBm
dBm
LO to IF Leakage fLO = 380MHz to 2200MHz
fLO = 2200MHz to 4000MHz
≤–42
≤–38
dBm
dBm
RF to LO Isolation fRF = 400MHz to 1700MHz
fRF = 1700MHz to 3800MHz
>50
>42
dB
dB
RF to IF Isolation fRF = 400MHz to 2300MHz
fRF = 2300MHz to 3800MHz
>41
>37
dB
dB
2RF-2LO Output Spurious Product
(fRF = fLO + fIF/2)
900MHz: fRF = 830MHz at –6dBm, fIF = 140MHz
1950MHz: fRF = 1830MHz at –6dBm, fIF = 240MHz
–61
–53
dBc
dBc
3RF-3LO Output Spurious Product
(fRF = fLO + fIF/3)
900MHz: fRF = 806.67MHz at –6dBm, fIF = 140MHz
1950MHz: fRF = 1790MHz at –6dBm, fIF = 240MHz
–83
–70
dBc
dBc
Input 1dB Compression RF = 450MHz, IF = 70MHz, High Side LO
RF = 900MHz, IF = 140MHz
RF = 1950MHz
RF = 2600MHz, IF = 360MHz
RF = 3600MHz, IF = 450MHz
10.0
8.8
8.8
8.6
9.1
dBm
dBm
dBm
dBm
dBm
Note 3: The LT5557 is guaranteed functional over the –40°C to 85°C
operating temperature range.
Note 4: SSB Noise Figure measurements performed with a small-signal
noise source and bandpass filter on RF input, and no other RF signal
applied.
ac elecTrical characTerisTics
PARAMETER CONDITIONS MIN TYP MAX UNITS
LO Input Return Loss ZO = 50Ω, 1000MHz to 5000MHz (No External Matching) >10 dB
IF Output Impedance Differential at 240MHz 529Ω||2.6pF R||C
LO Input Power 1200MHz to 4200MHz
380MHz to 1200MHz
–8
–5
–3
0
2
5
dBm
dBm
Test circuit shown in Figure 1. (Notes 2, 3)
LT5557
4
5557fc
Typical perForMance characTerisTics
Conversion Gain and IIP3
vs Temperature (Low Side LO)
Conversion Gain and IIP3
vs Temperature (High Side LO)
1950MHz Conversion Gain, IIP3
and NF vs Supply Voltage
1750MHz Conversion Gain, IIP3
and NF vs LO Power
1950MHz Conversion Gain, IIP3
and NF vs LO Power
2150MHz Conversion Gain, IIP3
and NF vs LO Power
Conversion Gain, IIP3 and NF
vs RF Frequency
LO Leakage and RF Isolation vs
LO and RF Frequency
Supply Current vs Supply Voltage
VCC = 3.3V, Test circuit shown in Figure 1.
Midband (no external RF/LO matching) 240MHz IF output, PRF = –6dBm (–6dBm/tone for 2-tone IIP3 tests, ∆f = 1MHz), PLO = –3dBm,
unless otherwise noted.
RF FREQUENCY (GHz)
1.6
GC (dB), NF (dB), IIP3 (dBm)
14
22
26
2.0
5557 G01
10
6
12
18
24
20
16
8
4
21.7 1.8 1.9 2.32.1 2.2
TA = 25°C
IF = 240MHz
GC
IIP3
SSB NF
LOW SIDE LO
HIGH SIDE LO
LO/RF FREQUENCY (GHz)
1.2
LO LEAKAGE (dBm)
RF ISOLATION (dB)
–40
–30
2.4
5557 G02
–50
–60 1.5 1.8 2.1 2.7
–20
35
45
25
15
55
RF-LO
RF-IF
LO-IF
LO-RF TA = 25°C
PLO = –3dBm
SUPPLY VOLTAGE (V)
2.9
SUPPLY CURRENT (mA)
83
85
87
3.7
5557 G03
81
79
82
84
86
80
78
77 3.1 3.3 3.5 3.9
85°C
60°C
25°C
–10°C
–40°C
TEMPERATURE (°C)
–50
GC (dB), IIP3 (dBm)
13
21
27
50
5557 G04
9
5
11
17
25
23
19
15
7
3
1–25 025 10075
IF = 240MHz
IIP3
1750MHz
1950MHz
2150MHz
GC
TEMPERATURE (°C)
–50
GC (dB), IIP3 (dBm)
13
21
27
50
5557 G05
9
5
11
17
25
23
19
15
7
3
1–25 025 10075
IF = 240MHz
IIP3
1750MHz
1950MHz
2150MHz
GC
SUPPLY VOLTAGE (V)
2.9
GC (dB), NF (dB), IIP3 (dBm)
12
20
26
3.7
5557 G06
8
4
10
16
24
22
18
14
6
2
03.1 3.3 3.5 3.9
LOW SIDE LO
IF = 240MHz
IIP3
SSB NF
–40°C
25°C
85°C
GC
LO INPUT POWER (dBm)
–9
GC (dB), NF (dB), IIP3 (dBm)
13
21
27
–1
5557 G07
9
5
11
17
25
23
19
15
7
3
1–7 –5 –3 31
IIP3
GC
LOW SIDE LO
IF = 240MHz
SSB NF
–40°C
25°C
85°C
LO INPUT POWER (dBm)
–9
GC (dB), NF (dB), IIP3 (dBm)
12
20
26
–1
5557 G08
8
4
10
16
24
22
18
14
6
2
0–7 –5 –3 31
IIP3
GC
LOW SIDE LO
IF = 240MHz
SSB NF
–40°C
25°C
85°C
LO INPUT POWER (dBm)
–9
GC (dB), NF (dB), IIP3 (dBm)
12
20
26
–1
5557 G09
8
4
10
16
24
22
18
14
6
2
0–7 –5 –3 31
IIP3
GC
LOW SIDE LO
IF = 240MHz
SSB NF
–40°C
25°C
85°C
LT5557
5
5557fc
Typical perForMance characTerisTics
Conversion Gain Distribution
at 1950MHz
IIP3 Distribution at 1950MHz
SSB Noise Figure Distribution
at 1950MHz
Conversion Gain, IIP3 and NF
vs RF Frequency
450MHz Conversion Gain,
IIP3 and NF vs LO Power
LO Leakage vs LO Frequency
450MHz and 900MHz Applications
IF Output Power, IM3 and IM5
vs RF Input Power (2 Input Tones)
IFOUT, 2 × 2 and 3 × 3 Spurs
vs RF Input Power (Single Tone)
2 × 2 and 3 × 3 Spurs
vs LO Power (Single Tone)
VCC = 3.3V, Test circuit shown in Figure 1.
Midband (no external RF/LO matching) 240MHz IF output, PRF = –6dBm (–6dBm/tone for 2-tone IIP3 tests, ∆f = 1MHz), PLO = –3dBm,
unless otherwise noted.
450MHz application (with external RF/LO matching) 70MHz IF output, PRF = –6dBm (–6dBm/tone for 2-tone IIP3 tests,
∆f = 1MHz), high side LO at 0dBm, unless otherwise noted.
RF INPUT POWER (dBm/TONE)
–18
–100
OUTPUT POWER/TONE (dBm)
–80
–60
–40
–20
–12 –9–15 –6 –3
5557 G10
0
0
–90
–70
–50
–30
–10
10
IFOUT
TA = 25°C
RF1 = 1949.5MHz
RF2 = 1950.5MHz
LO = 1710MHz
IM3 IM5
RF INPUT POWER (dBm)
–15
OUTPUT POWER (dBm)
–65
–5
5
15
–9 –3 0
5557 G11
–85
–25
–45
–75
–15
–95
–35
–55
–12 –6 63 9 12
IFOUT
(RF = 1950MHz)
2RF-2LO
(RF = 1830MHz)
3RF-3LO
(RF = 1790MHz)
TA = 25°C
LO = 1710MHz
IF = 240MHz
LO INPUT POWER (dBm)
–9
RELATIVE SPUR LEVEL (dBc)
–65
–60
–55
–3 1
5557 G12
–70
–75
–80 –7 –5 –1
–50
–45
–40
3
2RF-2LO
(RF = 1830MHz)
3RF-3LO
(RF = 1790MHz)
TA = 25°C
LO = 1710MHz
IF = 240MHz
PRF = –6dBm
CONVERSION GAIN (dB)
2.6
DISTRIBUTION (%)
25
30
35
3.2
5557 G25
15
02.7 2.8 2.9 3.0 3.1
40
20
10
5
TA = 25°C
LOW SIDE LO
IF = 240MHz
IIP3 (dBm)
23
0
DISTRIBUTION (%)
5
15
20
25
35
24
5557 G26
10
30
27 28
25 26
85°C
25°C
–40°C
LOW SIDE LO
IF = 240MHz
SSB NOISE FIGURE (dB)
11.0
DISTRIBUTION (%)
18
24
30
11.8
5557 G27
12
6
15
21
27
9
3
011.2 11.4 11.6 12.0 12.2
TA = 25°C
LOW SIDE LO
IF = 240MHz
RF FREQUENCY (MHz)
400
GC (dB), NF (dB), IIP3 (dBm)
10
22
24
26
450
5557 G13
6
4
18
14
8
20
2
16
12
425 475 500
HIGH SIDE LO
TA = 25°C
IF = 70MHz
IIP3
SSB NF
GC
LO INPUT POWER (dBm)
–6
GC (dB), NF (dB), IIP3 (dBm)
9
21
23
25
–2 24
5557 G14
5
3
17
13
7
19
1
15
11
–4 06
IIP3
GC
HIGH SIDE LO
IF = 70MHz
SSB NF
–40°C
25°C
85°C
LO FREQUENCY (MHz)
400
LO LEAKAGE (dBm)
–50
–45
1200
5557 G15
–55
–60 600 800 1000
–35
–40
TA = 25°C
PLO = 0dBm
LO-RF
LO-IF
450MHz
APPLICATION
900MHz
APPLICATION
LT5557
6
5557fc
Typical perForMance characTerisTics
Conversion Gain, IIP3 and SSB
NF vs RF Frequency
2.6GHz Conversion Gain, IIP3 and
NF vs LO Power
LO Leakage and RF Isolation
vs LO and RF Frequency
Conversion Gain, IIP3 and SSB
NF vs RF Frequency
3.6GHz Conversion Gain, IIP3 and
SSB NF vs LO Power
LO Leakage and RF Isolation
vs LO and RF Frequency
Conversion Gain, IIP3 and NF
vs RF Frequency
900MHz Conversion Gain, IIP3
and NF vs LO Power
IFOUT, 2 × 2 and 3 × 3 Spurs
vs RF Input Power (Single Tone)
VCC = 3.3V, Test circuit shown in Figure 1.
900MHz application (with external RF/LO matching), 140MHz IF output, PRF = –6dBm (–6dBm/tone for 2-tone IIP3 tests, ∆f = 1MHz),
low side LO at 0dBm, unless otherwise noted.
2.3GHz to 2.7GHz application (with external RF matching) 360MHz IF output, PRF = –6dBm (–6dBm/tone for 2-tone IIP3 tests,
∆f = 1MHz), PLO = –3dBm, unless otherwise noted.
3.3GHz to 3.8GHz application (with external RF matching) 450MHz IF output, PRF = –6dBm (–6dBm/tone for 2-tone IIP3 tests,
∆f = 1MHz), low side LO at –3dBm, unless otherwise noted.
RF FREQUENCY (MHz)
750
GC (dB), NF (dB), IIP3 (dBm)
14
22
28
950
5557 G16
10
6
12
18
26
24
20
16
8
4
2800 850 900 10501000
LOW SIDE LO
TA = 25°C
IF = 140MHz
IIP3
SSB NF
GC
LO INPUT POWER (dBm)
GC (dB), NF (dB), IIP3 (dBm)
13
27
5557 G17
9
5
11
17
19
21
23
25
15
7
3
1
LOW SIDE LO
IF = 140MHz
IIP3
SSB NF
GC
–40°C
25°C
85°C
RF INPUT POWER (dBm)
–15
OUTPUT POWER (dBm)
–75
–15
5
–5
15
–9 –3 0
5557 G18
–35
–55
–85
–25
–95
–45
–65
–12 –6 63 9 12
IFOUT
(RF = 900MHz)
2RF-2LO
(RF = 830MHz)
3RF-3LO
(RF = 806.67MHz)
TA = 25°C
LO = 760MHz
IF = 140MHz
RF FREQUENCY (GHz)
2.3
GC (dB), NF (dB), IIP3 (dBm)
12
20
26
5557 G19
8
4
10
16
24
22
18
14
6
2
02.4 2.5 2.6 2.7
TA = 25°C
GC
IIP3
SSB NF
LOW SIDE LO
HIGH SIDE LO
LO INPUT POWER (dBm)
–9
GC (dB), NF (dB), IIP3 (dBm)
12
20
26
–1
5557 G20
8
4
10
16
24
22
18
14
6
2
0–7 –5 –3 31
LOW SIDE LO
IIP3
SSB NF
GC
–40°C
25°C
85°C
LO/RF FREQUENCY (GHz)
LO LEAKAGE (dBm)
RF ISOLATION (dB)
5557 G21
1.9
–60
–50
–40
–30
–20
5
15
25
35
45
2.1 2.3 2.5 2.7 2.9 3.1
RF-LO
RF-IF
LO-IF
LO-RF
RF FREQUENCY (GHz)
3.3
GC (dB), NF (dB), IIP3 (dBm)
8
20
22
24
3.5 3.7
5557 G22
4
16
12
6
18
0
2
14
10
3.4 3.6 3.8
TA = 25°C
GC
IIP3
SSB NF
LO INPUT POWER (dBm)
–9
GC (dB), NF (dB), IIP3 (dBm)
8
20
22
24
–5 –1 1
5557 G23
4
2
16
12
6
18
0
14
10
–7 –3 3
IIP3
SSB NF
GC
–40°C
25°C
85°C
LO/RF FREQUENCY (GHz)
2.8
LO LEAKAGE (dBm)
RF ISOLATION (dB)
–50
–40
3.6
5557 G24
–60
–70 3.0 3.2 3.4 3.8
–30
35
45
25
15
55
RF-LO
RF-IF
LO-IF
LO-RF
LT5557
7
5557fc
pin FuncTions
NC (Pins 1, 2, 4, 8, 13, 14, 16): Not Connected Internally.
These pins should be grounded on the circuit board for
the best LO-to-RF and LO-to-IF isolation.
RF (Pin 3): Single-Ended Input for the RF Signal. This pin
is internally connected to the primary side of the RF input
transformer, which has low DC resistance to ground. If
the RF source is not DC blocked, then a series blocking
capacitor must be used. The RF input is internally matched
from 1.6GHz to 2.3GHz. Operation down to 400MHz or
up to 3.8GHz is possible with simple external matching.
EN (Pin 5): Enable Pin. When the input enable voltage is
higher than 2.7V, the mixer circuits supplied through Pins
6, 7, 10 and 11 are enabled. When the input voltage is less
than 0.3V, all circuits are disabled. Typical input current
is 53µA for EN = 3.3V and 0µA when EN = 0V. The EN pin
should not be left floating. Under no conditions should
the EN pin voltage exceed VCC + 0.3V, even at start-up.
VCC2 (Pin 6): Power Supply Pin for the Bias Circuits.
Typical current consumption is 3.3mA. This pin should
be externally connected to the VCC1 pin and decoupled
with 1000pF and 1µF capacitors.
VCC1 (Pin 7): Power Supply Pin for the LO Buffer Circuits.
Typical current consumption is 25.1mA. This pin should
be externally connected to the VCC2 pin and decoupled
with 1000pF and 1µF capacitors.
GND (Pins 9, 12): Ground. These pins are internally con-
nected to the backside ground for improved isolation.
They should be connected to the RF ground on the circuit
board, although they are not intended to replace the primary
grounding through the backside contact of the package.
IF–, IF+ (Pins 10, 11): Differential Outputs for the IF
Signal. An impedance transformation may be required to
match the outputs. These pins must be connected to VCC
through impedance matching inductors, RF chokes or a
transformer center tap. Typical current consumption is
26.6mA each (53.2mA total).
LO (Pin 15): Single-Ended Input for the Local Oscillator
Signal. This pin is internally connected to the primary side
of the LO transformer, which is internally DC blocked. An
external blocking capacitor is not required. The LO input
is internally matched from 1GHz to 5GHz. Operation down
to 380MHz is possible with simple external matching.
Exposed Pad (Pin 17): Circuit Ground Return for the En-
tire IC. This must be soldered to the printed circuit board
ground plane.
block DiagraM
15
7
11
3
65
10
DOUBLE-BALANCED
MIXER
LIMITING
AMPLIFIERS
LO
VCC2
VCC1
VCC1
EN
IF+
12
GND
17
EXPOSED
PAD
IF–
9
GND
5557 BD
BIAS
RF
VREF
REGULATOR
LT5557
8
5557fc
TesT circuiTs
Figure 1. Standard Downmixer Test Schematic—Transformer-Based Bandpass IF Matching (240MHz IF)
IFOUT
240MHz
5557 F01
16 15 14 13
5 6 7 8
12
11
10
9
NC NC
GND
GND
EN
EN
VCC2 VCC1
NC
RF
LO NC
NC
1
2
3
4NC
NC
IF+
IF–
RFIN
LOIN
T1
C4
ZO
50Ω
C1 C2
C3
3
VCC (2.9V to 3.9V)
LT5557
L4
C5
C5
3.9pF
RFIN
L5
3.6nH
L (mm)
LOWPASS MATCH
FOR 450MHz, 900MHz
AND 3.6GHz RF
EXTERNAL MATCHING
FOR LO BELOW 1GHz
*HIGHPASS MATCH
FOR 2.6GHz RF
RF
GND
GND
BIAS
εR = 3.7
0.015"
0.015"
0.062"
2
1
4
6
• •
APPLICATION RF MATCH LO MATCH IF MATCH
RF LO IF L C5 L4 C4 L1 C3
450MHz High Side 70MHz 6.5mm 12pF 10nH 8.2pF 270nH 15pF
900MHz Low Side 140MHz 1.7mm 3.9pF 2.7nH 3.9pF 180nH 3.9pF
2.6GHz 360MHz HIGHPASS* – – 47nH 1.2pF
3.6GHz 450MHz 2.9mm 1pF – – 39nH –
L1
DC1131A
BOARD
STACK-UP
(NELCO N4000-13)
Figure 2. Downmixer Test Schematic—Discrete IF Balun Matching (240MHz IF)
IFOUT
240MHz
5557 F02
16 15 14 13
5 6 7 8
12
11
10
9
NC NC
GND
GND
EN
EN
VCC2 VCC1
NC
RF
LO NC
NC
1
2
3
4
EXTERNAL MATCHING
FOR LO BELOW 1GHz
NC
NC
IF+
IF–
RFIN
LOIN
L1
L2
L3
C4
ZO
50Ω
C1 C2
C6
C3
C7
DISCRETE
IF BALUN
VCC (2.9V to 3.9V)
LT5557
L4
C5
L (mm)
LOWPASS MATCH
FOR 450MHz, 900MHz
AND 3.6GHz RF
RF
GND
GND
BIAS
εR = 4.4
0.018"
0.018"
0.062"
DC910A
BOARD
STACK-UP
(FR-4)
REF DES VALUE SIZE PART NUMBER REF DES VALUE SIZE PART NUMBER
C1, C3 1000pF 0402 AVX 04025C102JAT L4, C4, C5 0402 See Applications Information
C2 1µF 0603 AVX 0603ZD105KAT L1, L2 100nH 0603 Toko LL1608-FSLR10J
C6, C7 4.7pF 0402 AVX 04025A4R7CAT L3 150nH 0603 Toko LL1608-FSLR15J
REF DES VALUE SIZE PART NUMBER REF DES VALUE SIZE PART NUMBER
C1 1000pF 0402 AVX 04025C102JAT L4, C4, C5 0402 See Applications Information
C2 1µF 0603 AVX 0603ZD105KAT L1 82nH 0603 Toko LLQ1608-F82NG
C3 2.2pF 0402 AVX 04025A2R2BAT T1 8:1 Mini-Circuits TC8-1+
LT5557
9
5557fc
applicaTions inForMaTion
Introduction
The LT5557 consists of a high linearity double-balanced
mixer, RF buffer amplifier, high speed limiting LO buffer
amplifier and bias/enable circuits. The RF and LO inputs
are both single ended. The IF output is differential. Low
side or high side LO injection can be used.
Two evaluation circuits are available. The standard evalua-
tion circuit, shown in Figure 1, incorporates transformer-
based IF matching and is intended for applications that
require the highest dynamic range and the widest IF
bandwidth. The second evaluation circuit, shown in Fig-
ure 2, replaces the IF transformer with a discrete IF balun
for reduced solution cost and size. The discrete IF balun
delivers higher conversion gain, but slightly degraded IIP3
and noise figure, and reduced IF bandwidth.
RF Input Port
The mixer’s RF input, shown in Figure 3, consists of an
integrated transformer and a high linearity differential
amplifier. The primary terminals of the transformer are
connected to the RF input (Pin 3) and ground. The sec-
ondary side of the transformer is internally connected to
the amplifier’s differential inputs. The DC resistance of the
primary is 4.2Ω. If the RF source has DC voltage present,
then a coupling capacitor must be used in series with
the RF input pin.
The RF input is internally matched from 1.6GHz to 2.3GHz,
requiring no external components over this frequency
range. The input return loss, shown in Figure 4a, is typi-
cally 12dB at the band edges. The input match at the lower
band edge can be optimized with a series 3.9pF capacitor
at Pin 3, which improves the 1.6GHz return loss to greater
than 25dB. Likewise, the 2.3GHz match can be improved
to greater than 25dB with a series 1.5nH inductor. A
series 2.7nH/2.2pF network will simultaneously optimize
the lower and upper band edges and expand the RF input
bandwidth to 1.2GHz-2.5GHz. Measured RF input return
losses for these three cases are also plotted in Figure 4a.
Alternatively, the input match can be shifted as low as
400MHz or up to 3800MHz by adding a shunt capacitor
(C5) to the RF input. A 450MHz input match is realized with
C5 = 12pF, located 6.5mm away from Pin 3 on the evalua-
tion board’s 50Ω input transmission line. A 900MHz input
match requires C5 = 3.9pF, located at 1.7mm. A 3.6GHz
input match is realized with C5 = 1pF, located at 2.9mm.
Figure 3. RF Input Schematic
(4a) Series Reactance Matching
(4b) Series Shunt Matching
Figure 4. RF Input Return Loss with
and without External Matching
RFIN ZO = 50Ω
L = L (mm)
C5
RF
5557 F03
RFIN C5
L5
LOWPASS MATCH
FOR 450MHz, 900MHz
and 3.6GHz RF
HIGHPASS MATCH
FOR 2.6GHz RF
AND WIDEBAND RF
TO
MIXER
3
FREQUENCY (GHz)
0.2
–30
RF PORT RETURN LOSS (dB)
–25
–20
–15
–10
1.2 2.2 3.2 4.2
5557 F04a
–5
0
0.7 1.7 2.7 3.7
SERIES 2.7nH
AND 2.2pF
NO EXT MATCH
SERIES 1.5nH
SERIES 3.9pF
FREQUENCY (GHz)
0.2
–30
RF PORT RETURN LOSS (dB)
–25
–20
–15
–10
1.2 2.2 3.2 4.2
5557 F04b
–5
0
0.7 1.7 2.7 3.7
450MHz
L = 6.5mm
C5 = 12pF
2.6GHz
SERIES 3.9pF
SHUNT 3.6nH
3.6GHz
L = 2.9mm
C5 = 1pF
900MHz
L = 1.7mm
C5 = 3.9pF
NO EXT
MATCH
LT5557
10
5557fc
applicaTions inForMaTion
This series transmission line/shunt capacitor matching to-
pology allows the LT5557 to be used for multiple frequency
standards without circuit board layout modifications. The
series transmission line can also be replaced with a series
chip inductor for a more compact layout.
Input return losses for the 450MHz, 900MHz, 2.6GHz
and 3.6GHz applications are plotted in Figure 4b. The
input return loss with no external matching is repeated
in Figure 4b for comparison. The 2.6GHz RF input match
uses the highpass matching network shown in Figures 1
and 3 with C5 = 3.9pF and L5 = 3.6nH. The highpass in-
put matching network is also used to create a wideband
or dual-band input match. For example, with C5 = 3.3pF
and L5 = 10nH, the RF input is matched from 800MHz to
2.2GHz, with optimum matching in the 800MHz to 1.1GHz
and 1.6GHz to 2.2GHz bands, simultaneously.
RF input impedance and S11 versus frequency (with no
external matching) are listed in Table 1 and referenced
to Pin 3. The S11 data can be used with a microwave
circuit simulator to design custom matching networks
and simulate board level interfacing to the RF input filter.
Table 1. RF Input Impedance vs Frequency
FREQUENCY
(MHz)
INPUT
IMPEDANCE
S11
MAG ANGLE
50 4.6 + j2.3 0.832 174.7
300 9.1 + j11.2 0.706 153.8
450 12.0 + j14.5 0.639 145.8
600 14.7 + j17.4 0.588 138.7
900 20.5 + j23.3 0.506 123.4
1300 34.4 + j30.3 0.380 97.5
1700 59.6 + j23.8 0.229 55.8
1950 69.2 + j2.8 0.163 6.9
2200 59.2 – j18.1 0.184 –53.5
2450 41.5 – j24.5 0.274 –94.2
2700 28.3 – j21.3 0.374 –120.3
3000 19.0 – j13.5 0.481 –145.5
3300 13.9 – j5.1 0.568 –167.3
3600 10.8 + j3.4 0.645 171.9
3900 9.4 + j12.3 0.700 151.4
LO Input Port
The mixer’s LO input, shown in Figure 5, consists of an
integrated transformer and high speed limiting differential
amplifiers. The amplifiers are designed to precisely drive
the mixer for the highest linearity and the lowest noise
figure. An internal DC blocking capacitor in series with the
transformer’s primary eliminates the need for an external
blocking capacitor.
The LO input is internally matched from 1GHz to 5GHz.
The input match can be shifted down, as low as 750MHz,
with a single shunt capacitor (C4) on Pin 15. One exam-
ple is plotted in Figure 6 where C4 = 2.7pF produces a
750MHz to 1GHz match.
LO input matching below 750MHz requires the series
inductor (L4)/shunt capacitor (C4) network shown in
Figure 5. Two examples are plotted in Figure 6, where L4
= 2.7nH/C4 = 3.9pF produces a 650MHz to 830MHz match
and L4 = 10nH/C4 = 8.2pF produces a 460MHz to 560MHz
match. The evaluation boards do not include pads for L4,
so the circuit trace needs to be cut near Pin 15 to insert
L4. A low cost multilayer chip inductor is adequate for L4.
Figure 5. LO Input Schematic
Figure 6. LO Input Return Loss
LOIN
C4
L4 LO
VCC2
LIMITER
VREF
5557 F05
EXTERNAL
MATCHING
FOR LO < 1GHz TO
MIXER
15
REGULATOR
LO FREQUENCY (GHz)
0.3
L4 = 10nH
C4 = 8.2pF
L4 = 2.7nH
C4 = 3.9pF L4 = 0
C4 = 2.7pF
–30
LO PORT RETURN LOSS (dB)
–10
0
1 5
5557 G06
–20
NO EXT
MATCH
LT5557
11
5557fc
applicaTions inForMaTion
The optimum LO drive is –3dBm for LO frequencies above
1.2GHz, although the amplifiers are designed to accom-
modate several dB of LO input power variation without
significant mixer performance variation. Below 1.2GHz,
0dBm LO drive is recommended for optimum noise figure,
although –3dBm will still deliver good conversion gain
and linearity.
Custom matching networks can be designed using the port
impedance data listed in Table 2. This data is referenced
to the LO pin with no external matching.
Table 2. LO Input Impedance vs Frequency
FREQUENCY
(MHz)
INPUT
IMPEDANCE
S11
MAG ANGLE
50 10.0 – j326 0.991 –17.4
300 8.5 – j41.9 0.820 –99.2
500 11.8 – j10.1 0.632 –155.9
700 18.8 + j10.9 0.474 151.8
900 35.0 + j27.4 0.350 100.8
1200 72.9 + j19.3 0.241 31.3
1500 70.0 – j12.6 0.196 –26.1
1800 55.0 – j17.0 0.167 –64.3
2200 47.8 – j9.7 0.102 –97.2
2600 53.6 – j1.9 0.039 –26.8
3000 66.7 + j0.7 0.143 2.1
3500 82.1 – j13.9 0.263 –17.4
4000 69.0 – j30.1 0.290 –43.5
4500 43.7 – j13.2 0.154 –107.5
5000 36.4 + j19.8 0.271 111.6
IF Output Port
The IF outputs, IF+ and IF–, are internally connected to the
collectors of the mixer switching transistors (see Figure 7).
Both pins must be biased at the supply voltage, which
can be applied through the center tap of a transformer or
through matching inductors. Each IF pin draws 26.6mA
of supply current (53.2mA total). For optimum single-
ended performance, these differential outputs should
be combined externally through an IF transformer or a
discrete IF balun circuit. The standard evaluation board
(see Figure 1) includes an IF transformer for impedance
transformation and differential to single-ended transfor-
mation. A second evaluation board (see Figure 2) realizes
the same functionality with a discrete IF balun circuit.
The IF output impedance can be modeled as 560Ω in
parallel with 2.6pF at low frequencies. An equivalent small-
signal model (including bondwire inductance) is shown
in Figure 8. Frequency-dependent differential IF output
impedance is listed in Table 3. This data is referenced
to the package pins (with no external components) and
includes the effects of IC and package parasitics. The IF
output can be matched for IF frequencies as low as several
kHz or as high as 600MHz.
Table 3. IF Output Impedance vs Frequency
FREQUENCY (MHz)
DIFFERENTIAL OUTPUT
IMPEDANCE (RIF || XIF)
1 560 || – j63.7k (2.6pF)
70 556 || – j870 (2.6pF)
140 551 || – j440 (2.6pF)
190 523 || – j320 (2.6pF)
240 529 || – j254 (2.6pF)
300 509 || – j200 (2.66pF)
360 483 || – j163 (2.7pF)
450 448 || – j125 (2.83pF)
600 396 || – j92 (2.88pF)
Two methods of differential to single-ended IF matching
are described:
• Transformer-basedbandpass
• DiscreteIFbalun
Figure 7. IF Output with External Matching
Figure 8. IF Output Small-Signal Model
11
10
IF+
L1
8:1
5557 F07
IF–
VCC
C3 VCC
IFOUT
50Ω
11
10
IF+
0.7nH
0.7nH
5557 F08
IF–
RSCSRIF || XIF
LT5557
12
5557fc
applicaTions inForMaTion
Transformer-Based Bandpass IF Matching
The standard evaluation board (shown in Figure 1) uses
an L-C bandpass IF matching network, with an 8:1 trans-
former connected across the IF pins. The L-C network
maximizes mixer performance at the desired IF frequency.
The transformer performs impedance transformation and
provides a single-ended 50Ω output.
The value of L1 is calculated as:
L1 = 1/[(2πfIF)2•CIF]
where CIF is the sum of C3 and the internal IF capacitance
(listed in Table 3). The value of C3 is selected such that L1
falls on a standard value, while satisfying the desired IF
bandwidth. The IF bandwidth can be estimated as:
BWIF = 1/(2πREFFCIF)
where REFF, the effective IF resistance when loaded with
the transformer and inductor loss, is approximately 200Ω.
Below 40MHz, the magnitude of the internal IF reactance
is relatively high compared to the internal resistance. In
this case, L1 (and C3) can be eliminated, and the 8:1
transformer alone is adequate for IF matching.
The LT5557 was characterized with IF frequencies of
70MHz, 140MHz, 240MHz, 360MHz and 450MHz. The
values of L1 and C3 used for these frequencies are tabu-
lated in Figure 1 and repeated in Figure 9. In all cases,
L1 is a high-Q 0603 wire-wound chip inductor, for high-
est conversion gain. Low cost multilayer chip inductors
can be substituted, with a slight reduction in conversion
gain. The measured IF output return losses are plotted in
Figure 9.
Discrete IF Balun Matching
For many applications, it is possible to replace the IF
transformer with the discrete IF balun shown in Figure 2.
The values of L1, L2, C6 and C7 are calculated to realize
a 180 degree phase shift at the desired IF frequency and
provide a 50Ω single-ended output, using the following
equations. Inductor L3 is calculated to cancel the internal
2.6pF capacitance. L3 also supplies bias voltage to the IF+
pin. Low cost multilayer chip inductors are adequate for
L1, L2 and L3. C3 is a DC blocking capacitor.
L1, L2 =
RIF •ROUT
ωIF
C6,C7 =1
ωIF •RIF •ROUT
L3 =
XIF
ωIF
Figure 9. IF Output Return Loss with
Transformer-Based Bandpass Matching
IF FREQUENCY (MHz)
50
A: 70MHz, L1 = 270nH, C3 = 15pF
B: 140MHz, L1 = 180nH, C3 = 3.9pF
C: 240MHz, L1 = 82nH, C3 = 2.2pF
D: 360MHz, L1 = 47nH, C3 = 1.2pF
E: 450MHz, L1 = 39nH, C3 = 0pF
–30
IF PORT RETURN LOSS (dB0
–20
–10
0
150 250 350 450
5557 G09
550
A
B
CD E
LT5557
13
5557fc
applicaTions inForMaTion
These equations give a good starting point, but it is usually
necessary to adjust the component values after building
and testing the circuit. The final solution can be achieved
with less iteration by considering the parasitics of L3 in
the above calculations. Specifically, the effective parallel
resistance of L3 (calculated from the manufacturer’s Q
data) will reduce the value of RIF, which in turn influ-
ences the calculated values of L1 (= L2) and C6 (= C7).
Also, the effective parallel capacitance of L3 (taken from
the manufacturers SRF data) must be considered, since
it is in parallel with XIF (from Table 3). Frequently, the
calculated value for L1 does not fall on a standard value
for the desired IF. In this case, a simple solution is to load
the IF output with a high value external chip resistor in
parallel with L3, which reduces the value of RIF, until L1
is a standard value.
Discrete IF balun element values for four common IF fre-
quencies (190MHz, 240MHz, 360MHz and 450MHz) are
listed in Table 4. The 190MHz application circuit uses a
3.3k resistor in parallel with L3 as previously described.
The corresponding measured IF output return losses are
shown in Figure 10. Typical conversion gain, IIP3 and LO-IF
leakage, versus RF input frequency for all four examples is
shown in Figure 11. Typical conversion gain, IIP3 and noise
figure versus IF output frequency is shown in Figure 12.
Compared to the transformer-based IF matching technique,
this network delivers approximately 1dB higher conver-
sion gain (since the IF transformer loss is eliminated),
though noise figure and IIP3 are degraded slightly. The
most significant performance difference, as shown in
Figure 12, is the limited IF bandwidth available from the
discrete approach. For low IF frequencies, the absolute
bandwidth is small, whereas higher IF frequencies offer
wider bandwidth.
Table 5. Discrete IF Balun Element Values (ROUT = 50Ω)
IF FREQUENCY
(MHz)
L1, L2
C6, C7
L3
190 120nH 6.0pF 270nH || 3.3kΩ
240 100nH 4.7pF 150nH
360 56nH 3.0pF 82nH
450 47nH 2.2pF 47nH
Differential IF Output Matching
Figure 10. IF Output Return Losses with Discrete Balun Matching
Figure 11. Conversion Gain, IIP3 and LO-IF Leakage
vs RF Input Frequency and IF Output Frequency
(in MHz) Using Discrete IF Balun Matching
Figure 12. Conversion Gain, IIP3 and SSB NF vs IF Output
Frequency Using Discrete IF Balun Matching
IF FREQUENCY (MHz)
50
–30
IF PORT RETURN LOSS (dB)
–20
–10
0
150 250 350 450
5557 F10
550
190 MHz
240 MHz
360 MHz
450 MHz
RF INPUT FREQUENCY (MHz)
1700
GC (dB), IIP3 (dBm)
LO-IF LEAKAGE (dBm)
8
22
24
26
1900 2100
5557 F11
4
18
14
12
6
20
2
16
10
–60
–10
–30
–40
–20
–70
–50
1800 2000 2200
LOW SIDE LO (–3dBm)
TA = 25°C
LO-IF
IIP3
GC
190IF
240IF
360IF
450IF
IF OUTPUT FREQUENCY (MHz)
150
GC (dB), NF (dB), IIP3 (dBm)
10
22
24
26
250 350 400
5557 F12
6
18
14
8
20
2
4
16
12
200 300 450 500
RF = 1950MHz
LOW SIDE LO (–3dBm)
TA = 25°C
SSB NF
IIP3
GC
190IF
240IF
360IF
450IF
LT5557
14
5557fc
applicaTions inForMaTion
For fully differential IF architectures, the mixer’s IF outputs
can be matched directly into a SAW filter or IF amplifier,
thus eliminating the IF transformer. One example is shown
in Figure 13, where the mixer’s 500Ω differential output
resistance is matched into a 100Ω differential SAW filter
using the tapped-capacitor technique. Inductors L1 and
L2 form the inductive portion of the matching network,
cancel the internal 2.6pF capacitance, and supply DC bias
current to the mixer core. Capacitors C6 through C9 are
the capacitive portion of the matching, and perform the
impedance step-down.
The calculations for tapped-capacitor matching are cov-
Enable Interface
Figure 14 shows a simplified schematic of the EN pin
interface. The voltage necessary to turn on the LT5557
is 2.7V. To disable the chip, the enable voltage must be
less than 0.3V. If the EN pin is allowed to float, the chip
will tend to remain in its last operating state. Thus, it is
not recommended that the enable function be used in this
manner. If the shutdown function is not required, then the
EN pin should be connected directly to VCC.
The voltage at the EN pin should never exceed the power
supply voltage (VCC) by more than 0.3V. If this should
occur, the supply current could be sourced through the
EN pin ESD diode, potentially damaging the IC.
Figure 13. Differential IF Matching Using
the Tapped-Capacitor Technique
Figure 14. Enable Input Circuit
IF
AMP
SAW
FILTER
L1
C1 C2
IF+
IF–L2
C6
C7
C8
C9
SUPPLY
DECOUPLING
VCC
5557 F13
LT5557
22k
EN
VCC2
5557 F14
5
ered in the literature, and are not repeated here. Other
differential matching options include lowpass, highpass
and bandpass. The choice depends on the system per-
formance goals, IF frequency, IF bandwidth and filter
(or amplifier) input impedance. Contact the factory for
applications assistance.
LT5557
15
5557fc
Figure 15. Standard Evaluation Board Layout (DC1131A) Figure 16. Discrete IF Evaluation Board Layout (DC910A)
applicaTions inForMaTion
LT5557
16
5557fc
package DescripTion
4.00 ± 0.10
(4 SIDES)
NOTE:
1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WGGC)
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
PIN 1
TOP MARK
(NOTE 6)
0.55 ± 0.20
1615
1
2
BOTTOM VIEW—EXPOSED PAD
2.15 ± 0.10
(4-SIDES)
0.75 ± 0.05 R = 0.115
TYP
0.30 ± 0.05
0.65 BSC
0.200 REF
0.00 – 0.05
(UF16) QFN 10-04
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
0.72 ±0.05
0.30 ±0.05
0.65 BSC
2.15 ± 0.05
(4 SIDES)
2.90 ± 0.05
4.35 ± 0.05
PACKAGE
OUTLINE
PIN 1 NOTCH
R = 0.20 TYP
OR 0.35 × 45°
CHAMFER
UF Package
16-Lead Plastic QFN (4mm × 4mm)
(Reference LTC DWG # 05-08-1692)
LT5557
17
5557fc
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
revision hisTory
REV DATE DESCRIPTION PAGE NUMBER
C 6/11 Revised title and Features
Revised Absolute Maximum Ratings, Pin Configuration, DC Electrical Characteristics, AC Electrical Characteristics,
and Note 3
Updated Related Parts list
1
2, 3
18
(Revision history begins at Rev C)
LT5557
18
5557fc
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com
LINEAR TECHNOLOGY CORPORATION 2006
LT 0611 REV C • PRINTED IN USA
relaTeD parTs
PART NUMBER DESCRIPTION COMMENTS
Infrastructure
LT5512 1kHz to 3GHz High Signal Level Active Mixer 20dBm IIP3 from 30MHz to 900MHz, Integrated LO Buffer, HF/VHF/UHF Optimized
LT5514 Ultralow Distortion, IF Amplifier/ADC Driver
with Digitally Controlled Gain
850MHz Bandwidth, 47dBm OIP3 at 100MHz, 10.5dB to 33dB Gain Control Range
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
LT5517 40MHz to 900MHz Quadrature Demodulator 21dBm IIP3, Integrated LO Quadrature Generator
LT5519 0.7GHz to 1.4GHz High Linearity Upconverting Mixer 17.1dBm IIP3 at 1GHz, Integrated RF Output Transformer with 50Ω Matching,
Single-Ended LO and RF Ports Operation
LT5520 1.3GHz to 2.3GHz High Linearity Upconverting Mixer 15.9dBm IIP3 at 1.9GHz, Integrated RF Output Transformer with 50Ω Matching,
Single-Ended LO and RF Ports Operation
LT5521 10MHz to 3700MHz High Linearity
Upconverting Mixer
24.2dBm IIP3 at 1.95GHz, NF = 12.5dB, 3.15V to 5.25V Supply, Single-Ended
LO Port Operation
LT5522 400MHz 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
LT5525 High Linearity, Low Power Downconverting Mixer Single-Ended 50Ω RF and LO Ports, 17.6dBm IIP3 at 1900MHz, ICC = 28mA
LT5526 High Linearity, Low Power Downconverting Mixer 3V to 5.3V Supply, 16.5dBm IIP3, 100kHz to 2GHz RF, NF = 11dB, ICC = 28mA,
–65dBm LO-RF Leakage
LT5527 400MHz to 3.7GHz, 5V High Signal Level
Downconverting Mixer
23.5dBm IIP3 at 1.9GHz, NF = 12.5dB, Single-Ended RF and LO Ports
LT5528 1.5GHz to 2.4GHz High Linearity Direct I/Q
Modulator
21.8dBm OIP3 at 2GHz, –159dBm/Hz Noise Floor, 50Ω Interface at All Ports
LT5568 600MHz to 1.2GHz High Linearity Direct I/Q
Modulator
22.9dBm OIP3, –160.3dBm/Hz Noise Floor, –46dBc Image Rejection,
–43dBm Carrier Leakage
LT C
®
5569 300MHz to 4GHz 3.3V Dual Active
Downconverting Mixer
2dB Gain, 26.8dBm IIP3, 11.7dB NF at 1950MHz
RF Power Detectors
LTC5505 RF Peak Detectors with >40dB Dynamic Range 300MHz to 3GHz, Temperature Compensated, –32dBm to 12dBm
LTC5507 100kHz to 1000MHz RF Peak Power Detector 100kHz to 1GHz, Temperature Compensated, –34dBm to 14dBm
LTC5508 300MHz to 7GHz RF Peak Power Detector 44dB Dynamic Range, Temperature Compensated, SC70 Package,
–32dBm to 12dBm
LTC5509 300MHz to 3GHz RF Peak Power Detector 36dB Dynamic Range, Low Power Consumption, SC70 Package, –30dBm to 6dBm
LTC5530 300MHz to 7GHz Precision RF Peak Power Detector Precision VOUT Offset Control, Shutdown, Adjustable Gain, –32dBm to 10dBm
LTC5531 300MHz to 7GHz Precision RF Peak Power Detector Precision VOUT Offset Control, Shutdown, Adjustable Offset, –32dBm to 10dBm
LTC5532 300MHz to 7GHz Precision RF Peak Power Detector Precision VOUT Offset Control, Adjustable Gain and Offset,
±35mV Offset Voltage Tolerence
LTC5533 300MHz to 11GHz Dual Precision RF Peak Detector –32dBm to 12dBm, Adjustable Offset, 45dB Channel-to-Channel Isolation
LT5534 50MHz to 3GHz RF Log Detector with 60dB
Dynamic Range
±1dB Output Variation Over Temperature, 38ns Response Time
LTC5536 Precision 600MHz to 7GHz RF Peak Detector
with Fast Comparator Output
25ns Response Time, Comparator Reference Input, Latch Enable Input,
–26dBm to +12dBm Input Range
LT5537 90dB Dynamic Range RF Log Detector LF to 1GHz, –79dBm to 12dBm, Very Low Tempco
Low Voltage RF Building Block
LT5546 500MHz Quadrature Demodulator with VGA and
17MHz Baseband Bandwidth
17MHz Baseband Bandwidth, 40MHz to 500MHz IF, 1.8V to 5.25V Supply, –7dB to
56dB Linear Power Gain
