LINER LT5500EGN

LT5500
1.8GHz to 2.7GHz
Receiver Front End
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DESCRIPTIO
FEATURES
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The LT®5500 is a receiver front end IC designed for low
voltage operation. The chip contains a low noise amplifier
(LNA), a Mixer and an LO buffer. The IC is designed to
operate over a power supply voltage range from 1.8V to
5.25V.
1.8V to 5.25V Supply
Dual LNA Gain Setting: +13.5dB/–14dB at 2.5GHz
Double-Balanced Mixer
Internal LO Buffer
LNA Input Internally Matched
Low Supply Current: 23mA
Low Shutdown Current: 2µA
24-Lead Narrow SSOP Package
The LNA can be set to either high gain or low gain mode.
At 2.5GHz, the high gain mode provides 13.5dB gain and
a noise figure (NF) of 4dB. The LNA in low gain mode
provides –14dB gain and an IIP3 of + 8dBm at 2.5GHz.
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APPLICATIO S
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The mixer has 5dB of conversion gain and an IIP3 of
– 2.5dBm at 2.5GHz, with –10dBm LO input power.
IEEE 802.11 and 802.11b DSSS and FHSS
High Speed Wireless LAN
Wireless Local Loop
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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TYPICAL APPLICATIO
GAIN
SELECT
ENABLE
100pF
100pF
LT5500
EN
RF INPUT
FILTER
2V
L4
LO –
LNA_GND
LO +
2V
C4
C17
L3
LO INPUT
VCC
100pF
×4
1nF
LO
MIX_GND
RF
MIX_IN
IF
IF +
L5
•
L7
C23
INTERSTAGE
FILTER
5.8
13.8
5.6
13.7
5.4
13.6
5.2
13.5
5.0
13.4
4.8
13.3
4.6
13.2
4.4
13.1
4.2
13.0
1.5
2
2.5
3
3.5
4
4.5
5
5.5
4.0
VCC (V)
T2
8:1
IF OUTPUT
IF –
L9
6.0
fRF = 2.5GHz
13.9 TA = 25°C
MIXER CONVERSION GAIN (dB)
GND
14.0
L2
LNA_OUT
LNA GAIN (dB)
LNA_IN
RF
INPUT
1µF
LNA Gain (High Gain Mode)
and Mixer Conversion Gain
100pF
×2
GS
•
5500 TA02
2V
100pF
5500 F01
Figure 1. 2.5GHz Receiver. Interstage Filter is Optional
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LT5500
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ABSOLUTE MAXIMUM RATINGS
PACKAGE/ORDER I FOR ATIO
(Note 1)
Power Supply Voltage ........................................... 5.5V
LNA RF Input Power ............................................ 5dBm
Mixer RF Input Power ........................................ 10dBm
LO Input Power (Note 2) ................................... 10dBm
All Other Pins ......................................................... 5.5V
Operating Ambient
Temperature Range ............................... – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
ORDER PART
NUMBER
TOP VIEW
EN
1
24 GS
VCC
2
23 GND
LNA_IN
3
22 LNA_OUT
GND
4
21 VCC
LNA_GND
5
20 GND
LNA_GND
6
19 LO –
LNA_GND
7
18 LO +
LNA_GND
8
VCC
9
17 VCC
16 GND
MIX_GND 10
GND 11
IF + 12
LT5500EGN
15 MIX_IN
14 GND
13 IF –
GN PACKAGE
24-LEAD PLASTIC SSOP
TJMAX = 150°C, θJA = 85°C/W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
(Test circuit shown in Figure 3 for 1.8GHz application) VCC = 3V DC,
LNA: fLNA_IN = 1.8GHz, Mixer: fMIX_IN = 1.8GHz, fLO = 1.52GHz, PLO = –10dBm, TA = 25°C, unless otherwise noted. (Notes 3, 4)
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
LNA High Gain: EN = 1.35V, GS = 1.35V
Frequency Range (Note 3)
Forward Gain
15.5
Reverse Gain (Isolation)
1.8 to 2.7
GHz
18.5
dB
–39
dB
Noise Figure
Terminated 50Ω Source
2.5
dB
Input Return Loss
No External Matching
10.5
dB
Output Return Loss
With External Matching
15
dB
–24
dBm
–12
dBm
1.8 to 2.7
GHz
Input 1dB Compression
Input 3rd Order Intercept
Two Tone Test, ∆f = 2MHz
–18
LNA Low Gain: EN = 1.35V, GS = 0.3V
Frequency Range (Note 4)
Forward Gain
–10
dB
Reverse Gain (Isolation)
–13
–34
dB
Noise Figure
16.5
Input 1dB Compression
Input 3rd Order Intercept
Two Tone Test, ∆f = 2MHz
4.5
dB
0
dBm
9
dBm
1.8 to 2.7
GHz
8.5
dB
Mixer: EN = 1.35V, GS = 1.35V
RF Frequency Range (Note 4)
Conversion Gain
SSB Noise Figure
5.5
Terminated 50Ω Source
Input P1dB
Input 3rd Order Intercept
Two Tone Test, ∆f = 2MHz
–6
7.5
dB
–13
dBm
– 2.5
dBm
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LT5500
ELECTRICAL CHARACTERISTICS
(Test circuit shown in Figure 3 for 1.8GHz application) VCC = 3V DC,
LNA: fLNA_IN = 1.8GHz, Mixer: fMIX_IN = 1.8GHz, fLO = 1.52GHz, PLO = –10dBm, TA = 25°C, unless otherwise noted. (Notes 3, 4)
SYMBOL
PARAMETER
LO Frequency Range (Note 4)
IF Frequency Range (Note 3)
LO-IF Isolation
LO-RF Isolation
RF-LO Isolation
CONDITIONS
Matching Required
Matching Required
MIN
TYP
MAX
0.01 to 3.15
10 to 450
36
36
40
UNITS
GHz
MHz
dB
dB
dB
(Test circuit shown in Figure 3 for 2.5GHz application) VCC = 3V DC, LNA: fLNA_IN = 2.5GHz, Mixer: fMIX_IN = 2.5GHz, fLO = 2.22GHz,
PLO = –10dBm, TA = 25°C, unless otherwise noted.
SYMBOL PARAMETER
LNA High Gain: EN = 1.35V, GS = 1.35V
Forward Gain
Reverse Gain (Isolation)
Noise Figure
Input Return Loss
Output Return Loss
Input 1dB Compression
Input 3rd Order Intercept
LNA Low Gain: EN = 1.35V, GS = 0.3V
Forward Gain
Reverse Gain (Isolation)
Noise Figure
Input 1dB Compression
Input 3rd Order Intercept
Mixer: EN = 1.35V, GS = 1.35V
Conversion Gain
SSB Noise Figure
Input P1dB
Input 3rd Order Intercept
LO-IF Isolation
LO-RF Isolation
RF-LO Isolation
CONDITIONS
MIN
TYP
MAX
UNITS
Two Tone Test, ∆f = 2MHz
13.5
–35
4
12
15
–15
–3.5
dB
dB
dB
dB
dB
dBm
dBm
Two Tone Test, ∆f = 2MHz
–14
–39
19
–1
8
dB
dB
dB
dBm
dBm
5
9.5
–11
– 2.5
33
37
32
dB
dB
dBm
dBm
dB
dB
dB
Terminated 50Ω Source
No External Matching
With External Matching
Terminated 50Ω Source
Two Tone Test, ∆f = 2MHz
VCC = 3V DC, TA = 25°C (Note 4)
SYMBOL PARAMETER
Power Supply
VCC
Supply Voltage
ICC HG
Rx High Gain Mode
ICC LG
Rx Low Gain Mode
ICC Off
Shutdown Current
IEN
Enable Current
IGS
Gain Select Current
CONDITIONS
MIN
EN = 1.35V, GS = 1.35V
EN = 1.35V, GS = 0.3V
EN = 0.3V, GS = 0.3V
EN = 1.35V (Note 5)
GS = 1.35V (Note 6)
Note 1: Absolute Maximum Ratings are those values beyond which the life of
the device may be impaired.
Note 2: LO Absolute Maximum Ratings apply for each LO pin separately.
Note 3: Component values listed in Figure 3 for 1.8GHz evaluation board were
used to guarantee 1.8GHz performance.
TYP
1.8 to 5.25
23
18
2
21
21
MAX
33
31
25
UNITS
V
mA
mA
µA
µA
µA
Note 4: Specifications over the –40°C to 85°C operating temperature range
are assured by design, characterization and correlation with statistical process
controls.
Note 5: When EN ≤ 0.3V, enable current is <10µA.
Note 6: When GS ≤ 0.3V, gain select current is <10µA.
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TYPICAL PERFOR A CE CHARACTERISTICS
0
20
–40°C, 1.8GHz
–2
25°C, 1.8GHz
–4
18
IIP3 (dBm)
16
15
14
4.5
–40°C, 2.5GHz
–8
–40°C, 1.8GHz
–10
25°C, 1.8GHz
–12
85°C, 1.8GHz
–14
–40°C, 2.5GHz
–16
85°C, 2.5GHz
13
12
1.5
2.5 3 3.5 4 4.5
SUPPLY VOLTAGE (V)
5
1.5
5.5
2
3 3.5
2.5
4 4.5
SUPPLY VOLTAGE (V)
5
19.5
IIP3 (dBm)
–40°C, 2.5GHz
85°C, 2.5GHz
25°C, 1.8GHz
25°C, 2.5GHz
8
–13.0
–40°C, 1.8GHz
6
25°C, 2.5GHz
–14.0
–14.5
1.5
2
2.5 3 3.5 4 4.5
SUPPLY VOLTAGE (V)
5
4
1.5
5.5
2
4 4.5
2.5 3 3.5
SUPPLY VOLTAGE (V)
5500 G04
85°C, 1.8GHz
25°C, 2.5GHz
6
1.8GHz
2.5
3.5
4.5
SUPPLY VOLTAGE (V)
5.5
5500 G06
Mixer SSB Noise Figure
vs Supply Voltage
TA = 25°C
2.5GHz
9.5
85°C, 2.5GHz
–1
85°C, 1.8GHz
25°C, 2.5GHz
–2
25°C, 1.8GHz
–3
–40°C, 2.5GHz
5
5
5.5
5500 G07
8.5
8.0
1.8GHz
7.5
–5
–6
1.5
9.0
–40°C, 1.8GHz
–40°C, 2.5GHz
85°C, 2.5GHz
4 4.5
2.5 3 3.5
SUPPLY VOLTAGE (V)
17.0
10.0
–4
2
17.5
0
25°C, 1.8GHz
IIP3 (dBM)
CONVERSION GAIN (dB)
1
–40°C, 1.8GHz
7
18.0
16.0
1.5
5.5
2
8
18.5
Mixer IIP3 vs Supply Voltage and
Temperature
10
9
2.5GHz
5500 G05
Mixer Conversion Gain vs Supply
Voltage and Temperature
4
1.5
5
TA = 25°C
16.5
–40°C, 2.5GHz
85°C, 2.5GHz
NOISE FIGURE (dB)
GAIN (dB)
–11.5
NOISE FIGURE (dB)
10
25°C, 1.8GHz
5.5
19.0
85°C, 1.8GHz
–11.0
5
LNA Noise Figure vs Supply
Voltage (Low Gain Mode)
12
85°C, 1.8GHz
4 4.5
2.5 3 3.5
SUPPLY VOLTAGE (V)
2
5500 G03
–40°C, 1.8GHz
–13.5
1.8GHz
2.0
1.5
5.5
LNA IIP3 vs Supply Voltage and
Temperature (Low Gain Mode)
–10.0
–12.5
3.0
5500 G02
LNA Gain vs Supply Voltage and
Temperature (Low Gain Mode)
–12.0
3.5
–18
5500 G01
–10.5
2.5GHz
2.5
–20
2
TA = 25°C
4.0
85°C, 2.5GHz
–6
85°C, 1.8GHz
17
25°C, 2.5GHz
25°C, 2.5GHz
NOISE FIGURE (dB)
19
GAIN (dB)
LNA Noise Figure vs Supply
Voltage (High Gain Mode)
LNA IIP3 vs Supply Voltage and
Temperature (High Gain Mode)
LNA Gain vs Supply Voltage and
Temperature (High Gain Mode)
2
2.5 3 3.5 4 4.5
SUPPLY VOLTAGE (V)
5
5.5
5500 G08
7.0
1.5
2
4 4.5
2.5 3 3.5
SUPPLY VOLTAGE (V)
5
5.5
5500 G09
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TYPICAL PERFOR A CE CHARACTERISTICS
Mixer SSB Noise Figure
vs LO Power
Mixer IIP3 vs LO Power
9
–1.0
8
–1.2
1.8GHz
15
IF = 280MHz
VCC = 3V
TA = 25°C
–1.4
7
13
4
3
NOISE FIGURE (dB)
2.5GHz
5
–1.8
–2.0
1.8GHz
–2.2
–2.4
2
1
0
0
–30
–5
–15
–20
–10
P(LO) (dBm)
LNA Input Return Loss
vs Supply Voltage
18
RF = 2.5GHz
14 TA = 25°C
9
8
12
10
8
3.5
6
–50
5.5
VCC (V)
12
6
1.5
100
0
50
TEMPERATURE (°C)
ICC vs Supply Voltage
(Low Gain Mode)
26
85°C
25
23
85°C
24
ICC (mA)
ICC (mA)
16
5.5
28
27
10
4.5
5500 G15
29
12
3.5
2.5
VCC (V)
31
LOW GAIN
LOW GAIN
14
ICC vs Supply Voltage
(High Gain Mode)
HIGH GAIN
RETURN LOSS (dB)
16
5500 G14
RF = 2.5GHz
VCC = 3V
14
HIGH GAIN
18
8
5500 G13
LNA Output Return Loss
vs Temperature
–30
10
LOW GAIN
4.5
–25
RF = 2.5GHz
22 TA = 25°C
LOW GAIN
2.5
–20
–15
P(LO) (dBm)
20
14
7
6
1.5
–10
24
RETURN LOSS (dB)
RETURN LOSS (dB)
RETURN LOSS (dB)
10
–5
LNA Output Return Loss
vs Supply Voltage
HIGH GAIN
11
0
5500 G11
RF = 2.5GHz
VCC = 3V
16
HIGH GAIN
12
18
7
–30
LNA Input Return Loss
vs Temperature
15
20
–25
5500 G12
5500 G10
13
2.5GHz
10
1.8GHz
–3.0
–25
11
8
–2.8
–10
–15
–20
P(LO) (dBm)
–5
0
12
9
2.5GHz
–2.6
IF = 280MHz
VCC = 3V
TA = 25°C
IF = 280MHz
VCC = 3V
TA = 25°C
14
–1.6
6
IIP3 (dBm)
CONVERSION GAIN (dB)
Mixer Conversion Gain
vs LO Power
25°C
22
20
25°C
21
18
19
16
17
14
–40°C
8
–40°C
6
–50
50
0
TEMPERATURE (°C)
100
15
1.5
2.5
3.5
4.5
5.5
VCC (V)
5500 G16
12
1.5
2.5
3.5
4.5
5.5
VCC (V)
5500 G17
5500 G18
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LT5500
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PIN FUNCTIONS
EN (Pin 1): Enable Pin. A voltage less than 0.3V (Logic Low)
disables the part. An input greater than 1.35V (Logic High)
enables the part. This pin should be bypassed to ground with
a 100pF capacitor. To shut down the part, this pin and GS
(Pin 24) must be logic low. Voltage on this pin should not
exceed VCC nor fall below ground.
The output can be taken differentially or transformed into
a single ended output, depending on user preference and
performance requirements.
VCC (Pins 2, 9, 17, 21): Power Supply Pins. See Figure 6
for recommended power supply bypassing.
LO +, LO – (Pins 18, 19): LO Input Pins. These pins are
used to provide the LO drive to the mixer. The signal can
be provided either single ended or differentially. These
pins are internally biased to VCC – 0.2V and must be AC
coupled.
LNA_IN (Pin 3): LNA Input Pin. The LT5500 has better
than 10dB input return loss from 1.8GHz to 2.7GHz. This
pin is internally biased to 0.8V and must be AC coupled.
GND (Pin 4, 11, 14, 16, 20, 23): Ground Pins. These pins
should be connected directly to ground.
LNA_GND (Pins 5, 6, 7, 8): LNA Ground Pins. These pins
control the gain of the LNA. At higher frequencies, these
pins must be connected directly to ground to maximize the
gain.
MIX_GND (Pin 10): Mixer Ground Pin. To optimize the
performance of the mixer, a 4.7nH inductor to ground is
required for this pin.
IF +, IF – (Pins 12, 13): Intermediate Frequency (IF) Mixer
Output Pins. These pins must be inductively tied to VCC.
MIX_IN (Pin 15): Mixer RF Input. This pin is internally
biased to 0.83V and must be AC coupled. An external
matching network is necessary to match to a 50Ω system.
LNA_OUT (Pin 22): The Output Pin for the LNA. An
external matching network is necessary to match to a 50Ω
system. This pin must be DC coupled to the power supply.
GS (Pin 24): Gain Select Pin. This pin is used to select
between high gain and low gain modes. High gain mode is
selected when an input voltage greater than 1.35V (Logic
High) is applied to this pin. Low gain mode is selected
when the applied voltage is less than 0.3V (Logic Low).
This pin should be bypassed to ground with a 100pF
capacitor. To shut down the part, this pin must be logic
low. Voltage on this pin should not exceed VCC nor fall
below ground.
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LT5500
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BLOCK DIAGRA
1 EN
3
4, 11, 14, 16, 20, 23
5
6
7
8
2, 9, 17, 21
LT5500
GS 24
BIAS
LNA_IN
LNA_OUT 22
GND
LNA_GND
LO – 19
LO + 18
VCC
LO
10 MIX_GND
RF
MIX_IN 15
IF
IF +
IF –
12
13
5500 BD
Figure 2. LT5500 Block Diagram
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APPLICATIONS INFORMATION
The LT5500 consists of an LNA, a Mixer, an LO buffer and
the associated bias circuitry. The chip is designed to be
compatible with IEEE802.11b wireless local area network
(WLAN), MMDS and other wireless applications. The LNA
and Mixer are designed to operate over an input frequency
range of 1.8GHz to 2.7GHz with a supply voltage of 1.8V
to 5.25V. The Mixer IF output frequency range is typically
10MHz to 450MHz with proper matching. The typical LO
drive is –10dBm. The LO buffer operation is broadband.
LNA
The LNA has two modes of operation: high gain and low
gain. In the high gain mode, the LNA is a cascode
amplifier. Package inductance is used to achieve better
than 10dB input return loss over the entire frequency
range. The input of the LNA must be AC coupled. The
linearity of the high gain mode of the LNA can be increased by adding inductance to LNA_GND. This will
reduce the gain and improve input return loss while
having little impact on the low gain mode. In low gain
mode, the LNA uses a capacitively coupled diode and a
resistively degenerated cascode to attenuate the incoming signal and maintain a moderate VSWR. The LNA
output is an open collector, and the matching circuit
requires a shunt inductor connected to the power supply
to provide the bias current. The component configuration
for matching and example component values are listed in
Figure 3. If it is desirable to reduce the gain further and
simultaneously broaden the LNA bandwidth, an additional shunt resistor to the power supply can be added to
the output to reduce the output quality factor (Q).
The LT5500 is designed to allow an interstage bandpass
filter to be introduced between the output of the LNA and
the input of the Mixer. If such an interstage filter is
unnecessary, the output of the LNA can be connected to
the Mixer input through a blocking capacitor and small
value resistor.
Mixer
The Mixer consists of a single-ended input differential pair
followed by a double-balanced mixer cell. The input matching configuration for the Mixer is shown in Figure 3. The
Mixer uses a 4.7nH external inductance to act as a high
frequency current source at the MIX_GND pin. Example
component values for matching the mixer input are tabulated in Figure 3.
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LT5500
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APPLICATIONS INFORMATION
GAIN
100pF SELECT
ENABLE 100pF
VCC
100pF
100pF
EN
LT5500
BIAS
GS
L4
LNA_IN
L2
LNA_OUT
RF OUT
RF INPUT
GND
APPLICATION DEPENDENT
COMPONENT VALUES
2.5GHz
RF INPUT 1.8GHz
2.7nH
4.7nH
L4
4.7nH
12nH
L2
1.8nH
4.7nH
L3
220pF
220pF
C4
10pF
10pF
C17
2.7nH
5.6nH
L9
1.5pF
1.8pF
C23
280MHz IF OUTPUT
L7
15nH
T1
TC8-1 MINI-CIRCUITS
C4
LO –
LNA_GND
LO +
VCC
C17
L3
LO INPUT
VCC
*
LO
MIX_GND
RF
L9
MIX_IN
IF
IF +
L5
4.7nH
T1
IF OUTPUT
•
L7
•
MIXER RF
INPUT
C23
IF –
VCC
C2
100pF
*REFER TO FIGURE 6 FOR POWER SUPPLY
PINS BYPASSING RECOMMENDATION
5500 F03
Figure 3. Simplified Test Schematic for 1.8GHz and 2.5GHz Applications
An IF transformer can be used to create a single-ended
output. The additional discrete components necessary to
achieve a 50Ω match are tabulated in Figure 3. Alternatively, the discrete solution shown in Figure 4 can be used
to perform differential to single-ended conversion. For
best LO and RF signal suppression at the IF output, a
transformer should be used. If it is desirable to reduce the
gain of the mixer, a resistor between the IF outputs can be
used.
12
IF +
LT5500
IF –
19
LO –
100pF
C14
50Ω
IF OUTPUT
The LO inputs can be driven either differentially or single
ended. A single-ended configuration is shown along with
example component values in Figure 3. Optionally, the LO
can be driven differentially as shown in Figure 5.
13
VCC
L11
L10
LO Buffer
IF OUTPUT 280MHz
L10, L11
27nH
C12
3.3pF
C14
2.2pF
TX1
4:1
LO INPUT
LT5500
LO +
L3
18
5500 F05
C12
5500 F04
Figure 4. Alternative Mixer IF Output Matching
LO INPUT 2.22GHz
L3
3.3nH
TX1
TOKO-BF4
Figure 5. Optional Transformer-Based Differential LO Drive
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LT5500
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APPLICATIONS INFORMATION
Modes of Operation
evaluation of both transformer based and discrete component based matching.
The LT5500 has three operating modes:
1. Shutdown
2. LNA High Gain
3. LNA Low Gain
For shutdown, the EN pin and the GS pin must be at logic
Low. Logic Low is defined as a control voltage below 0.3V.
LNA High gain mode requires that both EN and GS pins be
at logic High. Logic High is defined as a control voltage
above 1.35V. LNA Low gain mode requires that the EN pin
be at logic High and that the GS pin be at logic Low. Mixer
operation is independent of the GS pin. The Mixer is
enabled when the EN pin is at logic High.
Table 1: Mode Selection
EN
GS
LNA
MIXER
High
High
High Gain
On
High
Low
Low Gain
On
Low
Low
Shutdown
Shutdown
Evaluation Board
Figure 6 shows the circuit schematic of the evaluation
board. Each signal terminal of the evaluation board has
provisions for three matching components in a T-formation. In practice, two or fewer components are needed to
achieve the match. In the case of the LNA input, no external
components are necessary if the band select filter provides the necessary AC coupling. Otherwise AC coupling
must be provided. A similar consideration applies to the
Mixer input pin. The LO terminal of the evaluation board
was designed to permit evaluation of both single ended
and differential matching configurations. The differential
configuration anticipates the use of a transformer. Similarly, the IF output board layout was designed to permit
The evaluation board employs primarily 0402 surface
mount components, particularly near the signal paths. All
surface mount inductors must have a high self-resonance
frequency. The component values necessary for 1.8GHz
and 2.5GHz applications are tabulated in Figure 3.
RF Layout Tips
• Use 50Ω impedance transmission lines up to the matching networks. Use of ground planes is a must, particularly beneath the IC.
• Keep the matching networks as close to the pins as
possible.
• Surface mount 0402 outline (or smaller) parts are
recommended to minimize parasitic capacitances and
inductances.
• Improve LO isolation and maximize component density
by putting the LO signal trace on the bottom of the
board. This permits either the matching components or
an interstage filter to be placed directly between the
LNA output and the Mixer input.
• Place bypass capacitors to ground in close proximity to
the pull-up inductors on the LNA and Mixer outputs to
improve component behavior and assure a good smallsignal ground.
• VCC lines must be decoupled with low impedance,
broadband capacitors to prevent instability. The capacitors should be placed as close as possible to the VCC
pins.
• Avoid use of long traces whenever possible. Long RF
traces in particular lead to signal radiation, degraded
isolation and higher losses.
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LT5500
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APPLICATIONS INFORMATION
VCC2
R1
5.1k
E1
R2
5.1k
VCC1
E2
4
3
C2
1µF
2
J2
LNA_IN
R3 0Ω R4 0Ω
C6
1µF
3
4
5
6
7
C9
100pF
8
9
10
L5
4.7nH
11
12
1
2
C24
100pF
C22
100pF
C25
100pF
C3
100pF
1
SW1
EN
VCC
GS
LT5500
LNA_IN
GND
GND
LNA_OUT
VCC
LNA_GND
GND
LNA_GND
LO–
LNA_GND
LO
+
LNA_GND
VCC
VCC
MIX_GND
GND
IF +
GND
MIX_IN
GND
IF –
VCC1
24
L4
2.7nH L2
4.7nH
VCC1
23
22
C16
8.2pF
J1
LNA_OUT
21
20
19 C4 220pF
C17
10pF
C5 100pF
18
C8 1µF
R6
0Ω
J3
LO_IN
L3
1.8nH
17
C10 100pF
16
15
14
L6
2.7nH
13
C28
1.5pF
3 T1 4
2
C13
1nF
C1
100pF
C15
100pF
1•
R5
0Ω
•6
L7
15nH
J5
MIX_IN
J6
IF_OUT
E4
E5
5500 F06
Figure 6. 2.5GHz Evaluation Circuit Schematic
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APPLICATIONS INFORMATION
Figure 7. Component Side Silkscreen of Evaluation Board
Figure 8. Component Side Layout of Evaluation Board
Figure 9. RF Ground (Layer 2) Layout of Evaluation Board
Figure 10. Routing (Layer 3) Layout of Evaluation Board
Figure 11. Bottom Side Silkscreen of Evaluation Board
Figure 12. Bottom Side Layout of Evaluation Board
5500f
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
LT5500
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PACKAGE DESCRIPTION
GN Package
24-Lead Plastic SSOP (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1641)
.337 – .344*
(8.560 – 8.738)
.033
(0.838)
REF
24 23 22 21 20 19 18 17 16 15 1413
.045 ±.005
.229 – .244
(5.817 – 6.198)
.254 MIN
.150 – .157**
(3.810 – 3.988)
.150 – .165
1
.0165 ± .0015
2 3
4
5 6
7
8
9 10 11 12
.0250 TYP
RECOMMENDED SOLDER PAD LAYOUT
.015 ± .004
× 45°
(0.38 ± 0.10)
.007 – .0098
(0.178 – 0.249)
.053 – .068
(1.351 – 1.727)
.004 – .0098
(0.102 – 0.249)
0° – 8° TYP
.016 – .050
(0.406 – 1.270)
.008 – .012
(0.203 – 0.305)
NOTE:
1. CONTROLLING DIMENSION: INCHES
INCHES
2. DIMENSIONS ARE IN
(MILLIMETERS)
3. DRAWING NOT TO SCALE
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
.0250
(0.635)
BSC
GN24 (SSOP) 0502
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PART NUMBER
DESCRIPTION
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300MHz to 7GHz RF Power Detector
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300MHz to 3GHz RF Power Detector
36dB Dynamic Range, SC70 Package
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LT5512
High Signal Level Downconverting Mixer
DC-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 Mixer
25dBm IIP3 at 900MHz, 21.5dBm IIP3 at 1.9GHz, Single-Ended 50Ω
Matched RF and LO Ports, Integrated LO Buffer
LTC5532
300MHz to 7GHz Precision RF Power Detector
Precision VOUT Offset Control, Adjustable Gain and Offset Voltage
ThinSOT is a trademark of Linear Technology Corporation.
5500f
12
Linear Technology Corporation
LT/TP 0305 1K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2005