Conexant RF210A, RF210B Datasheet

not
Do
use for new designs. Use the RF212 device instead
(Data Sheet No. 100780)
Dual-Band, Image-Reject Downconverters For GSM Applications
The RF210A and RF210B devices are available as a dual-band front end for Global System for Mobile Communications (GSM) handset applications. Both of these highly integrated, monolithic devices are optimized for dual-band use in GSM900/DCS1800 or GSM 900/PCS1900 applications. The devices include two Low Noise Amplifiers (LNAs), two image-reject mixers, and two Local Oscillator (LO) buffer amplifiers.
The main advantage of the RF210A and RF210B is their ability to provide 30 dB of image rejection for both the GSM900 and the DCS1800 (or PCS1900) bands without requiring the use of a post-LNA image reject filter. A block diagram of the RF210(A/B) is shown in Figure 1. The device package and pin configuration are shown in Figure 2.
LNA900GND
BIASGND
LNA900IN
0
90
90
IFOUT

Features

LNA/image-reject mixer for RF to IF conversion
10 dB (RF210A) or 20 dB (RF210B) switchable
gain for GSM
8 dB (RF210A) or 16 dB (RF210B) switchable gain for DCS/PCS
30 dB of image rejection. No post-LNA filtering required
High isolation LO input buffer
Differential IF output
High dynamic range
Three-cell battery operation (2.7 to 5 V)
20-pin Thin Shrink Small Outline Package
(TSSOP)

Applications

Dual-band digital cellular mobile telephony (GSM900/DCS 1800 or GSM900/PCS1900)
NC
1
2
3
20
19
18
MIXVCC
MIXGND
BYP900
GAINSEL
LNA1800IN
BANDSEL
Data Sheet
IRM
0
90
BIAS
BYP900
BYP1800
Figure 1. RF210(A/B) Block Diagram
Proprietary Information and Specifications are Subject to Change October 20, 1999
LOIN
C069
Conexant
LNA900IN
BIASVCC
LNAVCC
GAINSEL
LNA1800IN
LNA1800GND
ENA
4 5
6
7 8
9
10
Figure 2. RF210(A/B) Pin Configuration – 20-Pin TSSOP
IFOUT+
17
IFOUT-
16
BYP1800
15
BANDSEL
14
LOIN
13
LOGND
12
ADJMIX
11
C067
Doc. No. 100775A
RF210(A/B) Image-Reject Downconverter

Technical Description

The RF210(A/B) dual-band, image-reject downconverters implement the front-end functions of a dual-band super­heterodyne receiver. These devices consist of two receive paths, one for GSM900 and the other for DCS1800 (or PCS1900). Each receive path contains an LNA and an image­reject mixer. The IF and LO ports are common to both receive paths. The image-reject mixers can provide 30 dB of image rejection for both the GSM900 and the DCS1800 (or PCS1900) bands without using any post-LNA image reject filters.
The LNA/mixer combination has a switchable gain. The RF210A and RF210B both have 22 dB of gain in the high gain mode. For the RF210A, the gain is reduced by 10 dB (GSM band) and by 8 dB (DCS/PCS band) in the low gain mode. For the RF210B, the gain is reduced by 20 dB (GSM band) and by 16 dB (DCS/PCS band) in the low gain mode. The gain mode is selected using the GAINSEL pin (Pin 7). Low gain mode is selected by driving the GAINSEL signal high; high gain mode is selected by driving the signal low. In addition, small adjustments
Table 1. RF210(A/B) Signal Description
of the mixer gain can be accomplished by varying the quiescent current on the ADJMIX pin (Pin 11). This pin can be connected to VCC or ground through resistors. The current will increase if the pin is connected to GND and decrease if connected to VCC. For optimal performance, this pin should be left unconnected.
The band of operation for RF210(A/B) is selected by the BANDSEL signal on Pin 14. It switches the receive path between GSM900 and DCS1800 (or PCS1900) bands.
The device can operate from a three-cell battery pack (2.7 V to
5.0 V). Standby mode current is extremely low at 20 µA, which maximizes handset standby time.
The signal pin assignments and functional pin descriptions are found in Table 1. The absolute maximum ratings of the RF210(A/B) are provided in Table 2, the operating conditions are specified in Table 3, and electrical specifications are provided in Table 4. Figure 3 shows the diagram for a typical application circuit using the RF210(A/B) downconverter. Figure 4 provides the package dimensions for the 20-pin TSSOP device and Figure 5 provides the tape and reel dimensions.
Pin # Name Description Pin # Name Description
1 NC No connect 11 ADJMIX Mixer bias adjust pin 2 LNA900GND 900 MHz LNA ground 12 LOGND LO input ground
3 BIASGND Bias ground 13 LOIN LO input 4 LNA900IN 900 MHz LNA input 14 BANDSEL Band selection pin 5 BIASVCC Bias supply 15 BYP1800 Bypass capacitor for 1800 MHz band 6 LNAVCC LNA supply 16 IFOUT– Mixer output (negative) 7 GAINSEL LNA gain select 17 IFOUT+ Mixer output (positive) 8 LNA1800IN 1800 MHz LNA input 18 BYP900 Bypass capacitor for 900 MHz band 9 LNA1800GND 1800 MHz LNA ground 19 MIXGND Mixer ground
10 ENA Device enable (active high) 20 MIXVCC Mixer supply
Table 2. Absolute Maximum Ratings
Parameter Minimum Maximum Units
Storage Temperature –40 +125 °C LNA Input Power +5 dBm Supply Voltage (VCC) –0.3 +6 V Input Voltage Range –0.3 Vcc V
2 October 20, 1999 Proprietary Information and Specifications are Subject to Change
Conexant
100775A
Image-Reject Downconverter RF210(A/B)
Table 3. RF210(A/B) Recommended Operating Conditions
Parameter Min Typical Max Units
Supply Voltage 2.7 3.0 5.0 V Operating Temperature –30 +25 +85
°
C
Table 4. RF210(A/B) Electrical Specifications (1 of 2)
A
(T
= 25 C, Vcc = 3.0 V,
IF
f
= 400 MHz,
Plo
= –10 dBm)
Parameter Test Condition Min Typical Max Units
GSM900 Mode, BANDSEL = 0
Supply current:
Enable mode
Sleep mode RF Input frequency 935 960 MHz IF frequency 350 400 450 MHz LO frequency 1285 1410 MHz LO input power –10 dBm LO to RF input isolation 30 dB Input impedance LNA900IN = 950 MHz 40 – j50 Gain:
High gain (RF210A and RF210B)
Low gain (10 dB attenuation, RF210A)
Low gain (20 dB attenuation, RF210B)
Gain variation vs. Frequency
Gain step tracking error Noise figure:
High gain
Low gain (12 dB gain, RF210A)
Low gain (2 dB gain, RF210B)
High gain (Note 1)
Input 1 dB compression point –25 dBm Input third order i ntercept point –17 dBm IF shunt resis tance/side 400 500 600 Spurious response:
2(RF) x 2(LO) and 3(RF) x 3(LO)
(Note 2): Image rejection 35 dB
ENA = 1 ENA = 0
GAINSEL = 0 GAINSEL = 1 GAINSEL = 1
No blocker, GAINSEL = 0 GAINSEL = 1 GAINSEL = 1 –28 dBm blocker @ 915 MHz, GAINSEL = 0
Interferer input = –75 dBm –45 dB
38
22 12
2
0.5 1
3.3
9.0 17
3.9
10
0.5
3.9 11 19
mA
µ
dB dB dB dB dB
dB dB dB dB
A
100775A
Conexant
Proprietary Information and Specifications are Subject to Change October 20, 1999
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