Philips
Semiconductors
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
INTEGRATED CIRCUITS
Product specification
Supersedes data of 2000 Feb 11
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2
2000 Mar 13
853-2189 23308
DESCRIPTION
The SA2421 transceiver is a combined lownoise amplifier, receive
mixer, transmit mixer and LO buffer IC designed using a 20 GHz f
T
BiCMOS process, QUBiC2, for highperformance lowpower
communication systems for 2.42.5 GHz applications. The LNA has
a 3.2 dB noise figure at 2.45 GHz with 14.3 dB gain and an IP3
intercept of 3 dBm at the input. The widedynamicrange receive
mixer has a 11.2 dB noise figure and an input IP3 of +2.5 dBm at
2.45 GHz. The nominal current drawn from a single 3 V supply is
34 mA in transmit mode and 20 mA in receive mode. The SA2421
differs from the SA2420 by removal of the LO doubler and LO
switch. The LNA reverse isolation is improved, and a separate pin is
allocated for the transmit output.
FEATURES
Low current consumption: 34 mA nominal transmit mode and
20 mA nominal receive mode
High system power gain: 24 dB (LNA + Mixer) at 2.45 GHz
Excellent gain stability versus temperature and supply voltage
Separate Rx IN and Tx OUT pins
Wide IF range: 50500 MHz
10dBm typical LO input power
Improved LNA reverse isolation S12
TSSOP24 package
PIN CONFIGURATION
1
2
3
4
5
6
7
8
9
10
11
12
13
14
24
23
22
21
20
19
18
17
16
15
DH Package
ATTEN SW
Tx OUT
GND
Rx IN
GND
GND
GND
LNA OUT
V
CC
GND
GND
Rx IF OUT
GND
LOP
LNA IN
GND
GND
Rx IF OUT
Tx IF IN
Tx IF IN
Tx/Rx
LOM
V
CC
LO
CHIP EN
SR01756
Figure 1.
Pin configuration
APPLICATIONS
IEEE 802.11 (WLAN)
2.45 GHz ISM band
ORDERING INFORMATION
DESCRIPTION
TEMPERATURE RANGE
ORDER CODE
DWG #
24-Pin Plastic Thin Shrink Small Outline Package (Surface-mount, TSSOP)
40
C to +85
C
SA2421DH
SOT355-1
BLOCK DIAGRAM
4
3
2
1
5
24
23
22
21
20
7
6
10
9
8
19
18
17
16
15
Tx/Rx
GND
LOP
GND
V
CC
Rx IN
GND
ATTEN
SW
CHIP
EN
GND
GND
LNA
OUT
GND
LNA
GND
GND
12
11
14
13
LOM
LO
Tx OUT
GND
V
CC
LNA
IN
Rx IF
OUT
Rx IF
OUT
Tx IF
IN
Tx IF
IN
RX
RX
TX
LO
BUFFER
BPF
PRE-DRIVER
ATTENUATOR
SR01757
X1
Figure 2.
SA2421 block diagram
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
3
ABSOLUTE MAXIMUM RATINGS
SYMBOL
PARAMETER
RATING
UNITS
V
CC
Supply voltage
0.3 to +6
V
V
IN
Voltage applied to any pin
0.3 to (V
CC
+ 0.3)
V
P
D
Power dissipation, T
amb
= 25
C (still air)
24-Pin Plastic TSSOP
555
mW
T
JMAX
Maximum operating junction temperature
150
C
P
MAX
Maximum power (RF/IF/LO pins)
+20
dBm
T
STG
Storage temperature range
65 to +150
C
NOTES:
1. Transients exceeding these conditions may damage the product.
2. Maximum dissipation is determined by the operating ambient temperature and the thermal resistance, and absolute maximum ratings may
impact product reliability
JA
: 24-Pin TSSOP
= 117
C/W
3. IC is protected for ESD voltages up to 2000 V, human body model.
RECOMMENDED OPERATING CONDITIONS
SYMBOL
PARAMETER
RATING
UNITS
V
CC
Supply voltage
2.7 to 5.5
V
T
amb
Operating ambient temperature range
40 to +85
C
DC ELECTRICAL CHARACTERISTICS
V
CC
= +3V, T
amb
= 25
C; unless otherwise stated.
SYMBOL
PARAMETER
TEST CONDITIONS
LIMITS
UNITS
SYMBOL
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNITS
I
CCTX
Total supply current, Transmit
Tx/Rx = Hi
22
34
42
mA
I
CCRX
Total supply current, Receive
Tx/Rx mode = Lo,
LNA = Hi gain
14
20
26
mA
I
CC OFF
Power down mode
Tx/Rx = GND
Atten SW = V
CC
Enable = GND
10
A
V
LNA-IN
LNA input voltage
Receive mode
0.855
V
V
LO GHz
LO buffer DC input voltage
Tx/Rx = Lo
0.1
V
CC
V
V
TX IF
Tx Mixer input voltage
Tx/Rx = Hi
1.7
V
V
TX IFB
Tx Mixer input voltage
Tx/Rx = Hi
1.7
V
I
S
Input bias current
Logic 1
6
A
I
BIAS
Input bias current
Logic 0
0
A
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
4
AC ELECTRICAL CHARACTERISTICS
V
CC
= +3 V, T
amb
= 25
C; LO
IN
= 10 dBm @ 2.1 GHz; f
RF
= 2.45 GHz; unless otherwise stated.
SYMBOL
PARAMETER
TEST CONDITIONS
LIMITS
UNITS
SYMBOL
PARAMETER
TEST CONDITIONS
MIN
3
TYP
+3
MAX
UNITS
f
RF
RF frequency range
3
2.4
2.45
2.5
GHz
f
IF
IF frequency range
3
300
350
400
MHz
LNA High gain mode (In = Pin 2; Out = 23)
S
21
Amplifier gain
LNA gain = Hi
13.3
14.3
15.3
dB
S
12
Amplifier reverse isolation
LNA gain = Hi
32
dB
S
11
Amplifier input match
1
LNA gain = Hi
10
dB
S
22
Amplifier output match
1
LNA gain = Hi
9
dB
ISO
Isolation: LO
X
to LNA
IN
LNA gain = Hi
43
dB
P
-1dB
Amplifier input 1dB gain compression
LNA gain = Hi
15
dBm
IP3
Amplifier input third order intercept
f
1
- f
2
= 1 MHz,
LNA gain = Hi
4.5
3.2
1.9
dBm
NF
Amplifier noise figure (50
)
LNA gain = Hi
3.1
3.2
3.3
dB
LNA High Overload Mode (low gain mode)
S
21
Amplifier gain
LNA gain = Low
18.5
19.4
20.3
dB
S
12
Amplifier reverse isolation
LNA gain = Low
26
dB
S
11
Amplifier input match
1
LNA gain = Low
8
dB
S
22
Amplifier output match
1
LNA gain = Low
8
dB
ISO
Isolation: LO
X
to LNA
IN
LNA gain = Low
45
dB
P
-1dB
Amplifier input 1dB gain compression
LNA gain = Low
2
dBm
IP3
Amplifier input third order intercept
f
1
f
2
= 1 MHz,
LNA gain = Low
18
dBm
NF
Amplifier noise figure (50
)
LNA gain = Low
18.5
dB
Rx Mixer (Rx IN = Pin 19, IF = Pins 5 and 6, LO = Pin 10 or 12, P
LO
= 10 dBm)
PG
C
Power conversion gain into 50
:
matched to 50
W
using external balun
circuitry.
f
S
= 2.45 GHz,
f
LO
= 2.1 GHz,
f
IF
= 350 MHz
9.5
10
10.5
dB
S
11RF
Input match at RF (2.45 GHz)
1
11
dB
NF
M
SSB noise figure (2.45 GHz) (50
)
9.8
11.2
12.5
dB
P
-1dB
Mixer input 1 dB gain compression
10.5
dBm
IP3
Input third order intercept
f
1
f
2
= 1MHz
1.8
2.2
2.6
dBm
Rx Mixer Spurious Components (P
IN
= P
-1dB
)
P
RF-IF
RF feedthrough to IF
4
C
L
= 2 pF per side
-35
dBc
P
LO-IF
LO feedthrough to IF
5
C
L
= 2 pF per side
-32
dBc
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
5
AC ELECTRICAL CHARACTERISTICS (continued)
SYMBOL
PARAMETER
TEST CONDITIONS
LIMITS
UNITS
SYMBOL
PARAMETER
TEST CONDITIONS
MIN
3
TYP
+3
MAX
UNITS
Tx Mixer (Tx OUT = Pin 17, IF = Pins 7 and 8, LO = Pin 10 or 12, P
LO
= 10 dBm)
PG
C
Power conversion gain: R
L
= 50
R
S
= 50
f
S
= 2.45 GHz,
f
LO
= 2.1 GHz,
f
IF
= 350 MHz
22.5
23
23.5
dB
S
11RF
Output match at RF (2.45 GHz)
1
10
dB
NF
M
SSB noise figure (2.45 GHz) (50
)
10.9
11.2
11.5
dB
P
-1dB
Output 1dB gain compression
4.2
dBm
IP3
Output third order intercept
f
1
f
2
= 1 MHz
10.1
12.2
14.3
dBm
Tx Mixer Spurious Components (P
OUT
= P
1dB
)
P
IF-RF
IF feedthrough to RF
4
50
dBc
P
LO-RF
LO feedthrough to RF
5
22
dBc
P
IMAGE-RF
Image feedthrough to RF
6
20
dBc
LO Buffer
P
LO IN
LO drive level
15
10
5
dBm
S
11-LO
Mixer input match (LO = 2.1 GHz)
10
dB
f
LOG
LOG frequency range
3
1.9
2.1
2.3
GHz
Switching
2
t
Rx-Tx
Receive-to-transmit switching time
1
s
t
Tx-Rx
Transmit-to-Receive switching time
1
s
t
POWER UP
Chip enable time
1
s
t
PWR DWN
Chip disable time
1
s
NOTES:
1. With simple external matching
2. With 50 pF coupling capacitors on all RF and IF parts
3. This part has been optimized for the stated frequency range. Operation outside this frequency range may yield performance other than
specified in this datasheet.
4. Measured 5dB lower than 1dB compression point, with typical output matching network.
5. Measured at 1dB compression point.
6. With typical output matching network (no image reject mixer is used).
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
6
Table 1.
Truth Table
Chip-En
ATT-SW
T
X
R
X
Mode
LNA Gain
R
X
Mixer
T
X
Mixer and
Predriver
0
X
X
Sleep
N/S
off
off
1
1
0
Receive
+14.3 dB
on
off
1
0
0
Receive
19 dB
on
off
1
X
1
Transmit
N/S
off
on
FUNCTIONAL DESCRIPTION
The SA2421 is a 2.45 GHz transceiver front-end available in the
TSSOP-24 package. This integrated circuit (IC) consists of a low
noise amplifier (LNA) and up- and down-converters. There is an
enable/disable switch available to power up/down the entire chip in
1
s, typically. This transceiver has several unique features.
The LNA has two operating modes: 1) high gain mode with a gain =
+14.3 dB; and 2) low gain mode with a gain 19 dB. The switch for
this option is internal and is controlled externally by high and low
logic to the pin. When the LNA is switched into the attenuation
mode, active matching circuitry (on-chip) is switched in (reducing the
number of off-chip components required). To reduce power
consumption when the chip is transmitting, the LNA is automatically
switched into a "sleep" mode (internally) without the use of external
circuitry.
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
7
17
18
19
20
21
22
23
TEMPERATURE (
C)
Current (mA)
SR02262
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 3.
LNA / Receive Supply Current vs Supply Voltage and
Temperature
12
13
14
15
TEMPERATURE (
C)
Gain (dB)
SR02263
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 4.
LNA Gain vs Supply Voltage and Temperature
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
TEMPERATURE (
C)
IP3 (dBm)
SR02264
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 5.
LNA Input IP3 vs Supply Voltage and Temperature
2.8
3.0
3.2
3.4
3.6
3.8
4.0
TEMPERATURE (
C)
Noise (dB)
SR02265
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 6.
LNA Noise Figure vs Supply Voltage and
Temperature
8.5
9.5
10.5
11.5
TEMPERATURE (
C)
Gain dB
SR02266
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 7.
RX Gain vs Supply Voltage and Temperature
1
1.5
2.0
2.5
3.0
TEMPERATURE (
C)
IP3 (dBm)
SR02267
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 8.
Receive Input IP3 vs Supply Voltage and Temp
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
8
10
10.5
11.0
11.5
12.0
12.5
TEMPERATURE (
C)
NF (dB)
SR02268
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 9.
Receive Noise Figure vs Supply Voltage and Temp
13
12.5
12.0
11.5
11.0
10.5
10.0
9.5
9.0
TEMPERATURE (
C)
P1dB (dBm)
SR02269
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 10.
RX 1dB Compression vs Supply Voltage and Temp
30
31
32
33
34
35
36
37
38
TEMPERATURE (
C)
Current (mA)
SR02270
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 11.
Transmit Current vs Supply Voltage and Temp
15
17
19
21
23
25
27
29
TEMPERATURE (
C)
Gain (dB)
SR02271
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 12.
Transmit Gain vs Supply Voltage and Temp
0
2
4
6
8
10
12
14
16
18
20
TEMPERATURE (
C)
Output IP3 (dBm)
SR02272
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 13.
Transmit Output IP3 vs Supply Voltage and Temp
8
8.5
9.0
9.5
10.0
10.5
11.0
11.5
12.0
12.5
13.0
TEMPERATURE (
C)
NF (dB)
SR02273
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 14.
Transmit Noise Figure vs Supply Voltage and Temp
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
9
1
0
1
2
3
4
5
6
7
8
9
TEMPERATURE (
C)
P1dB (dBm)
SR02274
40
_
C
0
_
C
25
_
C
70
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 15.
TX 1dB compression vs Supply Voltage and Temp
18
17
16
15
14
13
12
11
10
TEMPERATURE (
C)
P1dB (dBm)
SR02275
40
_
C
25
_
C
85
_
C
2.7V
3.8V
3.0V
5.5V
Figure 16.
LNA 1dB compression vs Supply Voltage and Temp
7
7.5
8.0
8.5
9.0
9.5
10.0
10.5
11.0
11.5
12.0
LO Input (dBm)
Receive Gain (dB)
SR02276
40C
+25C
0C
+70C
+85C
18
16
14
12
10
8
5
2
Figure 17.
Receive Gain vs LO Input over Temp Range
17
18
19
20
21
22
23
24
25
26
LO Input (dBm)
T
ransmit Gain (dB)
SR02277
40C
+25C
0C
+70C
+85C
18
16
14
12
10
8
5
2
Figure 18.
Transmit Gain vs LO Input over Temp Range
The Rx IN port is matched to 50
and has an input IP3 of +2.2 dBm
(mixer only). The down-convert mixer is buffered and has open
collectors at the pins to allow for matching to common SAW filters.
The up convert mixer has an input pin to output pin gain of 23 dB.
The output of the up-converter is designed for a power level =
+4.2 dBm (P
1dB
).
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
10
GND
LNA
IN
GND
GND
Rx IF OUT
Rx IF OUT
Tx IF IN
Tx IF IN
GND
LOP
Tx/Rx
LOM
V
LNA
OUT
GND
GND
A
TTEN SW
Rx IN
GND
Tx OUT
GND
GND
CHIP
EN
cc
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
+
S3
V
cc
LNA
OUT
RxRF IN
C13
33pF
C12
100pF
S2
C15
.1uF
C17
10uF
C1
1pF
LNA
IN
C4
3.9pF
C9
8.2pF
C8
8.2pF
L4
33nH
J4
C10
100pF
U1
V
cc
SA2421
SR01758
Rx OUT
350MHz
TxRF OUT
L7
1.2nH
J7
J6
2.45GHz
J5
2.45GHz
C14
100pF
V
cc
2.7nH
L6
V
cc
V
cc
3.9nH
L1
J1
C3
10pF
C2
C16
100pF
V
cc
39nH
L2
C6
10pF
33nH
L3
C7
100pF
Tx IN
350MHz
J2
J3
S1
V
cc
LO 2.1GHz
L5
2.7nH
C1
1
1.0pF
V
cc
1
2
JP1
SEL
(0pF1.0pF)
C5
SEL
(0pF1.0pF)
LO
Figure 19.
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
11
TSSOP24:
plastic thin shrink small outline package; 24 leads; body width 4.4 mm
SOT355-1
Philips Semiconductors
Product specification
SA2421
2.45 GHz low voltage RF transceiver
2000 Mar 13
12
Definitions
Short-form specification -- The data in a short-form specification is extracted from a full data sheet with the same type number and title. For
detailed information see the relevant data sheet or data handbook.
Limiting values definition -- Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one
or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or
at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended
periods may affect device reliability.
Application information -- Applications that are described herein for any of these products are for illustrative purposes only. Philips
Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or
modification.
Disclaimers
Life support -- These products are not designed for use in life support appliances, devices or systems where malfunction of these products can
reasonably be expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications
do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application.
Right to make changes -- Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard
cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no
responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these
products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless
otherwise specified.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 940883409
Telephone 800-234-7381
Copyright Philips Electronics North America Corporation 2000
All rights reserved. Printed in U.S.A.
Date of release: 03-00
Document order number:
9397 750 06949
Philips
Semiconductors
Data sheet
status
Objective
specification
Preliminary
specification
Product
specification
Product
status
Development
Qualification
Production
Definition
[1]
This data sheet contains the design target or goal specifications for product development.
Specification may change in any manner without notice.
This data sheet contains preliminary data, and supplementary data will be published at a later date.
Philips Semiconductors reserves the right to make changes at any time without notice in order to
improve design and supply the best possible product.
This data sheet contains final specifications. Philips Semiconductors reserves the right to make
changes at any time without notice in order to improve design and supply the best possible product.
Data sheet status
[1]
Please consult the most recently issued datasheet before initiating or completing a design.
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