Philips UAA2073M-C1 Datasheet

DATA SH EET

Product speciﬁcation Supersedes data of July 1995 File under Integrated Circuits, IC03

1995 Dec 07

INTEGRATED CIRCUITS

UAA2073M

Image rejecting front-end for GSM applications

1995 Dec 07 2

Philips Semiconductors Product speciﬁcation

Image rejecting front-end for GSM applications

UAA2073M

FEATURES

• Low-noise, wide dynamic range amplifier

• Very low noise figure

• Dual balanced mixer for at least 30 dB; on-chip image

rejection

• IF I/Q combination network for 50 to 100 MHz

• Down-conversion mixer for closed-loop transmitters

• Independent TX/RX fast on/off power-down modes

• Very small outline packaging

• Very small application (no image filter).

APPLICATIONS

• 900 MHz front-end for GSM hand-portable equipment

• Compact digital mobile communication equipment

• TDMA receivers.

GENERAL DESCRIPTION

UAA2073M contains both a receiver front-end and a high frequency transmit mixer intended for GSM (Global System for Mobile communications) cellular telephones. Designed in an advanced BiCMOS process it combines high performance with low power consumption and a high degree of integration, thus reducing external component costs and total front-end size.

The main advantage of the UAA2073M is its ability to provide over 30 dB of image rejection. Consequently, the image filter between the LNA and the mixer is suppressed and the duplexer design is eased, compared with a conventional front-end design.

Image rejection is achieved in the internal architecture by two RF mixers in quadrature and two all-pass filters in I and Q IF channels that phase shift the IF by 45° and 135° respectively. The two phase shifted IFs are recombined and buffered to furnish the IF output signal.

For instance, signals presented at the RF input at LO + IF frequency are rejected through this signal processing while signals at LO − IF frequency can form the IF signal. An internal switch allows to reject the upper or lower image frequency. Image rejection is at an optimum when the IF is 71 MHz and local oscillator is above the wanted signal.

The receiver section consists of a low-noise amplifier that drives a quadrature mixer pair. The IF amplifier has on-chip 45° and 135° phase shifting and a combining network for image rejection.The IF driver has differential open-collector type outputs.

The LO part consists of an internal all-pass type phase shifter to provide quadrature LO signals to the receive mixers. The all-pass filters outputs are buffered before been fed to the receive mixers.

The transmit section consists of a down-conversion mixer and a transmit IF driver stage. In the transmit mode an internal LO buffer is used to drive the transmit IF down-conversion mixer.

All RF and IF inputs or outputs are balanced to reduce EMC issues.

Fast power-up switching is possible. A synthesizer-on (synthon) mode enables LO buffers independent of the other circuits. When SYNTHON pin is HIGH, all internal buffers on the LO path of the circuit are turned on, thus minimizing LO pulling when remainder of receive chain is powered-up.

ORDERING INFORMATION

TYPE NUMBER

PACKAGE

NAME DESCRIPTION VERSION

UAA2073M SSOP20 plastic shrink small outline package; 20 leads; body width 4.4 mm SOT266-1

1995 Dec 07 3

Philips Semiconductors Product speciﬁcation

Image rejecting front-end for GSM applications

UAA2073M

QUICK REFERENCE DATA

Note 1.

Note

1. For conditions see Chapters “DC characteristics” and “AC characteristics”.

BLOCK DIAGRAM

SYMBOL PARAMETER MIN. TYP. MAX. UNIT

supply voltage 3.6 3.75 5.3 V

CC(RX)

receive supply current 21 26 32 mA

CC(TX)

transmit supply current 9 12 15 mA

NF noise ﬁgure on demonstration board (including matching

and PCB losses)

− 3.25 4.3 dB

conversion power gain 20 23 26 dB IR image frequency rejection 30 37 − dB T

amb

operating ambient temperature −30 +25 +85 °C

Fig.1 Block diagram.

handbook, full pagewidth

MBG794

LNA

COMBINER

low-noise

amplifier

11 12 10

81718

RX TX IF LO

TXINATXINBLOINB

MIXER

LOINA

2 3

IFA

IFB

TXOIFA TXOIFB

n.c. n.c. SBS

QUADRATURE

PHASE

SHIFTER

CURRENT

REGULATORS

RFINA RFINB

GND1

RXON

TXON

SYNTHON

GND2

CC1

CC2

UAA2073M

RECEIVE SECTION

TRANSMIT SECTION

LOCAL OSCILLATOR

SECTION

1995 Dec 07 4

Philips Semiconductors Product speciﬁcation

Image rejecting front-end for GSM applications

UAA2073M

PINNING

SYMBOL PIN DESCRIPTION

SBS 1 sideband selection n.c. 2 not connected n.c. 3 not connected V

CC1

4 supply voltage for receive and

transmit sections RFINA 5 RF input A (balanced) RFINB 6 RF input B (balanced) GND1 7 ground 1 for receive and transmit

sections TXINA 8 transmit mixer input A (balanced) TXINB 9 transmit mixer input B (balanced) SYNTHON 10 hardware power-on of LO section

(including buffers to RX and TX) RXON 11 hardware power-on for receive

section and LO buffers to RX TXON 12 hardware power-on for transmit

section and LO buffers to TX TXOIFB 13 transmit mixer IF output B

(balanced) TXOIFA 14 transmit mixer IF output A

(balanced) V

CC2

15 supply voltage for LO section GND2 16 ground 2 for LO section LOINB 17 LO input B (balanced) LOINA 18 LO input A (balanced) IFB 19 IF output B (balanced) IFA 20 IF output A (balanced)

Fig.2 Pin configuration.

handbook, halfpage

UAA2073M

MBG793

1 2 3 4 5 6 7 8 9

20 19 18 17 16 15 14 13 12 11

SBS

n.c. n.c.

RFINA RFINB

GND1 TXINA TXINB

SYNTHON RXON

TXON

TXOIFB

TXOIFA

GND2

LOINB

LOINA

IFB

IFA

CC1

CC2

1995 Dec 07 5

Philips Semiconductors Product speciﬁcation

Image rejecting front-end for GSM applications

UAA2073M

FUNCTIONAL DESCRIPTION Receive section

The circuit contains a low-noise amplifier followed by two high dynamic range mixers. These mixers are of the Gilbert-cell type. The whole internal architecture is fully differential.

The local oscillator, shifted in phase to 45° and 135°, mixes the amplified RF to create I and Q channels. The two I and Q channels are buffered, phase shifted by 45° and 135° respectively, amplified and recombined internally to realize the image rejection.

Pin SBS allows sideband selection:

• f

LO<fRF

(SBS = 1)

• fLO>fRF (SBS = 0).

Balanced signal interfaces are used for minimizing crosstalk due to package parasitics. The RF differential input impedance is 150 Ω (parallel real part), choosen to minimize current consumption at best noise performance.

The IF output is differential and of the open-collector type, tuned for 71 MHz. Typical application will load the output with a differential 500 Ω load; i.e. a 500 Ω resistor load at each IF output, plus a 1 kΩ to x Ω narrow band matching network (x Ω being the input impedance of the IF filter). The path to V

for the DC current is achieved via tuning inductors. The output voltage is limited to VCC+3Vbe or 3 diode forward voltage drops.

Fast switching, on/off, of the receive section is controlled by the hardware input RXON.

Fig.3 Block diagram, receive section.

handbook, full pagewidth

MBG795

LNA

COMBINER

amplifier

MIXER

RXONSYNTHON

LOIN

IFA

IFB

SBS

RFINA RFINB

GND1

CC1

+45

+135

+ 11 hidden pages