Philips SA9503 Datasheet

INTEGRATED CIRCUITS

SA9503

Dual-band, CDMA/AMPS LNA and downconverter mixers

Objective specification Supersedes data of 1999 Jul 06

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1999 Jul 29

Philips Semiconductors Objective specification

PARAMETER

Dual-band, CDMA/AMPS LNA and downconverter mixers

DESCRIPTION

The SA9503 is an integrated CDMA/AMPS low noise amplifier (LNA) plus a downconverter, for both the 900 MHz Cellular band and the 1.9 GHz PCS band. The LNA incorporates 5 settings of digitally selected stepped gain in the Cellular band and in the PCS band. One of the modes (high linearity mode) in each of the Cellular and PCS bands, includes a high IP3 setting in order to meet the 1-tone CDMA desensitization test. The gain, noise figure and IP3 for the remaining 4 low current modes in the Cellular band, are designed in order to have sufficient separation between the antenna power levels at which the LNA gains are changed, based on multi-tone interference levels. A 3 dB overlap is allowed in the antenna power levels for the adjacent modes. Table 1 indicates a typical scenario.

The downconverter portion is based on our SA9502 and is designed to meet all the stringent spurious rejections that are required in the Cellular and PCS bands. There are three individual mixer blocks, each optimized for high linearity with low power consumption for operation in one of the following modes: 1900 MHz PCS CDMA, 800 MHz Cellular CDMA, or 800 MHz analog FM AMPS/TACS modes.

The circuit has been designed in our advanced QUBiC3 BiCMOS process with 30 GHz f

FEATURES Versatile step gain LNA

•Can meet single tone CDMA desensitization requirements

•Can meet CDMA two tone interference requirements

•Cellular

Gain (dB) 17 15.5 9 3 –4 Noise figure (dB) 2 1.6 1.9 4.5 11 Input IP3 (dBm) 5.5 –2 –3.5 2 15 Current (mA) 13.2 4.9 4.9 4.9 3.7

MODE

CEL_L CEL_1 CEL_2 CEL_3 CEL_4

SA9503

Downconverter typical performance

PARAMETER Cellular FM Cellular CDMA PCS CDMA

Gain (dB) 7.5 11.5 12.5 Nois e Figure ( dB) 10 9 9 Input IP3 (dBm) 5 3.5 4 Current (mA)

(Tx) LO output buffer off

•Separate, selectable IF outputs to suit FM and CDMA bandwidths

•Buffered Cellular and PCS LO inputs

•Integrated frequency doubler for PCS mixer LO

•Differential (Tx) LO output buffer (can be switched on or off)

•Low voltage operation down to 2.7 volts

•Mixers current consumption with (Tx) LO buffer on:

– Cellular FM: 16.8 mA – Cellular CDMA: 23 mA – PCS: 26 mA

•Low standby current in sleep mode: <50 µA

•BCC32++ package

APPLICATIONS

•800 MHz analog FM and CDMA digital receivers

•1900 MHz PCS band CDMA digital receivers

•Supports dual-band and triple-mode operation

•Digital mobile communications equipment

•Portable, low power radio equipment

6.8 13 16

•PCS

MODE

PCS_L PCS_1 PCS_2 PCS_3 PCS_4 Gain (dB) 15.2 14.3 8 2 –4.5 Noise figure (dB) 2.5 2 2.5 3.7 11.5 Input IP3 (dBm) 4.5 1 –2 –1 16 Current (mA) 13.3 5.9 5.9 5.9 3.7

BCC32++ is a trademark of Fujitsu Microelectronics.

1999 Jul 29

Philips Semiconductors Objective specification

PARAMETER

TEST CONDITIONS

UNIT

Dual-band, CDMA/AMPS LNA and downconverter mixers

BLOCK DIAGRAM

RF_PCS

SA9503

RF_CEL

RX BPF Fo = 1960 MHz BW = 60 MHz

PCS_INPCS_OUT

SA9503

PCS IF BPF

×2

CELLULARPCS

PCS_IF

CDMA_IF

FM_IF

BW = 1.23MHz

CDMA IF BPF BW = 1.23MHz

FM IF BPF BW = 30kHz

MODE

SELECT

LOGIC

CDMA/FM PCS/CELLULAR S0 S1 S2

CEL_OUT

CEL_IN

RX BPF Fo = 881.5MHz BW = 25 MHz

BIAS

CTRL

LO_OUT

LO_ENABLE CEL

LO_IN

PCS

LO_IN

Figure 1. SA9503 Block Diagram

ABSOLUTE MAXIMUM RATINGS

PARAMETER RATINGS UNIT

Supply voltage (VCC) –0.3 to +3.6 V Gain control voltage +3.6 V Logic input voltage –0.3 to VCC+0.3 V Maximum power input +20 dBm Power dissipation (T

= 25°C) 800 mW

amb

Storage temperature range –65 to +150 °C

RECOMMENDED OPERATING CONDITIONS

LIMITS

MIN TYP MAX

Supply voltage (VCC) 2.7 2.85 3.3 V Operating ambient temperature range (T Logic input signal levels

LOW level input voltage range (VIL) At logic 0 –0.3 0.2V HIGH level input voltage range (VIH) At logic 1 0.5V Input bias current (I

) At logic 1 or logic 0 –5 +5 µA

bias

) –40 +85 °C

amb

VCC+0.3 V

SR01935

1999 Jul 29

Philips Semiconductors Objective specification

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Dual-band, CDMA/AMPS LNA and downconverter mixers

FUNCTIONAL DESCRIPTION Mode selection

The SA9503 has several modes of operation for which the selection logic is defined in Tables 2 and 3. Different mode selections require different portions of the circuit to be active. Modes from unlisted combinations of logic pins are not permitted. The LNA and downconverter together can be programmed to operate in the PCS or cellular bands using the PCS/CEL logic input pin, and in CDMA or FM modes using the CDMA/FM logic input pin.

The LNA can be set to four different gain values and one special high linearity setting. Thus, the LNA can be programmed into five different modes with associated gain, noise figure, and input IP3, using the S0, S1, and S2 control lines. The whole circuit (LNAs and mixers) is powered down when control lines S0 = 1, S1 = 0, and S2 = 0. It is also possible to independently switch off the LNAs and keep the mixers on, as shown in Table 3.

LNA

External components can be used to match the LNA inputs, and if required, the outputs, for the Cellular and PCS bands. The input and output return loss of better than 10 dB can be achieved in all modes. For Cellular band FM, only the CEL_1 mode is required for the LNA.

For CDMA, LNA modes CEL_1 and PCS_1 are used for normal operation, as they have the highest gains and lowest noise figures. For higher levels of multi-tone interference, other modes with lower gains are to be used. The high linearity CEL_L and PCS_L modes are used when there is a very strong adjacent channel interference, while at the same time the mobile is transmitting close to its full power. The high linearity is required in order to reduce the cross modulation of the LNA from the mobile’s transmitter, in the presence of strong adjacent channel interferer. The maximum transmitter power leakage which can be tolerated at the LNA input is approximately –30dBm to meet the single tone desensitization requirements. The cross modulation power can be derived from:

Cellular band: (2 × P PCS band: (2 × P

The LNA requires less than one hundred microseconds to settle when it changes from one mode to another. This is expected to have insignificant impact on the CDMA frame error rate.

TX TX

+ P + P

JAMMER JAMMER

– 8) dBm – 10.5) dBm

SA9503

Downconverter

The SA9503 has three mixers, one for Cellular FM, one for Cellular CDMA, and one for PCS CDMA. Each one is individually optimized for their specific requirements. The Cellular CDMA and FM mixers have a common single-ended RF input.

The PCS mixer’s RF input port is differential, and requires an external balun when used with a single-ended source. Both the PCS and the Cellular mixer RF inputs should be AC coupled.

Local oscillator drive for the mixers is provided through pins CEL LO_IN and/or PCS LO_IN. The local oscillator inputs are single-ended, AC-coupled. The CEL LO_IN signal is internally buffered to drive the following: – (Tx) LO output buf fer,

– cellular FM mixer, – cellular CDMA mixer, – PCS LO frequency doubler.

In the PCS mode, mixer LO drive can be either direct (PCS LO_IN) or through the frequency doubler after CEL LO_IN. The mixer local oscillator signal is made available externally via the (Tx) LO output buffer for potential use elsewhere in the radio. For example, this signal typically can be used with the transmitter circuitry. The (Tx) LO output buffer can be powered down independently, using the (Tx) LO_ENABLE logic input. The (Tx) LO output buffer has open collector differential outputs which are internally biased to V

2 supply rail.

The PCS and Cellular CDMA mixers have open collector differential IF outputs. The two IF outputs can either supply two separate IF filters, or they can be connected together externally for use with one common receive IF filter. The differential IF outputs must be biased at the supply voltage through external inductors that may also be part of the matching circuit to the SAW filter . The cellular band FM mixer also has a differential open collector IF output.

Table 1. Typical Cellular Mode LNA Gain Change Points for 2-tone CDMA Interference Test

GAIN, dB

16.5 9 3

–3

1999 Jul 29

MAXIMUM ANTENNA IN-BAND POWER, dBm

–95 –90.5 –86.7 > –79

MINIMUM ANTENNA IN-BAND POWER, dBm

< –104

–98.5 –93.5 –89.7

Philips Semiconductors Objective specification

(Tx) LO

()

MODES

Dual-band, CDMA/AMPS LNA

SA9503

and downconverter mixers

MODE SELECT LOGIC AND DC CHARACTERISTICS

The SA9503 chip has several modes of operation for which the selection logic is defined in the following two tables. Different mode selections require different portions of the circuit to be active. Modes from unlisted combinations of logic pins, are not valid. Total current consumption of the device is the sum of the currents for the mixer portion (Table 2) and the LNA portion (Table 3).

Table 2. Mode logic definition for Downconverter mixers

VCC = 2.7 V to 3.3 V, 2.85 V typical; T

MODES

PCS

1 PCS1 On 2 GHz Off 1 1 0 1 26 29.9 2 PCS1 Idle Off — Off 1 1 0 0 16 18.4 3 PCS2 On 2 GHz On 1 1 1 1 30 34.5 4 PCS2 Idle Off — On 1 1 1 0 20 23

Cellular CDMA

5 CDMA On 1 GHz Off 1 0 1 1 23 26.5 6 CDMA Idle Off — Off 1 0 1 0 13 15 7 FM On 1 GHz Off 1 0 0 1 16.8 19.3 8 FM Idle Off — Off 1 0 0 0 6.8 7.8

Power Down

9 Sleep

NOTES:

x = Don’t care

1. The device will be in the Power Down mode (sleep) when control lines S0 = 1, S1 = 0, and S2 = 0.

BUFFER

x x Off 0 x x x 1 µA 50 µA

= –40 to +85 °C

amb

(Tx) LO

BUFFER

OUTPUT

DOUBLER

POWER DOWN

LOGIC INPUT PINS CURRENT (mA)

PCS/CEL

CDMA/FM

LO DOUBLER

(Tx) LO

ENABLE

TYP MAX

Table 3. Mode logic definition for LNA

VCC = 2.7 V to 3.3 V, 2.85 V typical; T

1 CEL_L (High linearity) 0 1 1 1 13.2 15.0 2 CEL_1 (High gain) 0 0 1 1 4.9 6.0 3 CEL_2 (Next lower gain) 0 0 1 0 4.9 6.0 4 CEL_3 (Next lower gain) 0 0 0 1 4.9 6.0 5 CEL_4 (Next lower gain) 0 0 0 0 3.7 4.5

6 PCS_L (High linearity) 1 1 1 1 13.3 15.0 7 PCS_1 (High gain) 1 0 1 1 5.9 7.2 8 PCS_2 (Lower gain) 1 0 1 0 5.9 7.2 9 PCS_3 (Next lower gain) 1 0 0 1 5.9 7.2

10 PCS_4 (Next lower gain) 1 0 0 0 3.7 4.5 11 Mixers ON (LNA portion OFF) x 1 1 0 1 µA 50 µA 12 Reserved (Sleep) x 1 0 1 (Note 1) (Note 1)

13 Sleep x 1 0 0 (Note 1) (Note 1)

NOTES:

x = Don’t care

1. The device will be in the Power Down mode (sleep) when control lines S0 = 1, S1 = 0, and S2 = 0.

= –40 to +85 °C

amb

LOGIC INPUTS CURRENT CONSUMPTION (mA)

PCS/CEL S0 S1 S2 TYP MAX

1999 Jul 29

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