Intersil Corporation HFA3766 Datasheet

HFA3766

PRELIMINARY

400MHz AGC Quadrature IF
Modulator/Demodulator

™

The HFA3766 is a highly integrated
baseband converter for quadrature
modulation applications. It features all
the necessary blocks for baseband

modulation and demodulation of I and
Q signals. It has a twostageintegratedAGCIFamplifierwith
82dB of voltage gain and 76dB of gain control range.
Baseband antialiasing is integrated into the design. Four
filter bandwidths are programmable via a two bit digital
control interface. In addition, these filters are continuously
tunable over a ±20% frequency range via one external
resistor. For baseband modulation digital I and Q data are
delivered to the transmit section. To achieve broadband
operation, the Local Oscillator frequency input is required
to be twice the desired frequency of modulation and
demodulation. A selectable buffered divide by 2 LO output
and a stable reference voltage are provided for convenience
of the user. The device is housed in a thin 80 lead TQFP
package well suited for PCMCIA board applications.

January 1999 File Number 4328.1

Features

• Integrates all IF Transmit and AGC Receive Functions

• Broad Frequency Range . . . . . . . . . . 10MHz to 400MHz

• I/Q Amplitude and Phase Balance . . . . 0.2dB, 2 Degrees

• 5th Order Programmable

Low Pass Filter. . . . . . . . . . . . . . . . . .2.2MHz to 17.6MHz

• 400MHz AGC Gain Strip . . . . . . . . . . . . . . . . . . . . . 82dB

• AGC Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75dB

• Low LO Drive Level . . . . . . . . . . . . . . . . . . . . . . . -15dBm

• Fast AGC Switching . . . . . . . . . . . . . . . . . . . . . . . . . . 1µs

• Fast Transmit-Receive Switching . . . . . . . . . . . . . . . . . . . 1µs

• Power Management/Standby Mode

• Single Supply 3.0V Operation

• Wireless Local Loop

• Wireless Local Area Networks

• PCMCIA Wireless Transceivers

• ISM Systems

• CDMA Radios

• PCS/Wireless PBX

Ordering Information

TEMP.

PART NUMBER

HFA3766IN -40 to 85 80 Ld TQFP Q80.14x14
HFA3766IN96 -40 to 85 Tape and Reel

RANGE (oC) PACKAGE PKG. NO.

Simplified

AGC_SEl

AGC1_IN

AGC1_VAGC
AGC2_VAGC

LO_IN

LO_OUT

LO_GND

MOD_TX_IF_OUT

1

AGC1_OUT

AGC2_IN

2V REF

2V REF

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

AGC2_OUT

∑

DEMOD_IFIN

÷2

0o/90

DEMOD_RXQ

I
M
U

o

X

Q

LPF_TXI

MOD_TXI

LPF_TXQ

MOD_TXQ

www.intersil.com or 407-727-9207 | Copyright © Intersil Corporation 1999

LPF_SEL0

LPF_SEL1

LPF_TUNE_0

LPF_RXI_OUT

LPF_RXQ _OUT

M
U
X

PRISM and PRISM logo are trademarks of Intersil Corporation.

LPF_TXI_IN

LPF_TXQ_IN

TX D OR A

LPF_TUNE_1

LPF_RXI

LPF_RXQ

DEMOD_RXI

Pinout

HFA3766

80 LEAD TQFP

TOP VIEW

AGC

AGC1_BYP+

AGC1_IN+

GND

AGC1_SEL

AGC1_IN-

AGC1_BYP-

GND
GND

LPF_V

CC

2V REF

LPF_BYP

LPF_TXI_IN

LPF_TXQ_IN

LPF_RXI_OUT

LPF_RXQ_OUT

LPF_SEL1

LPF_SEL0
LPF_TUNE1
LPF_TUNE0

TX D OR A

AGC1_VCCAGC1_PE

AGC1_OUT+

LPF_TXI-

LPF_TXI+

LPF_TXQ-

LPF_TXQ+

AGC1_OUT-

AGC1_VCCGND

LPF_RXQ-

GND

GND

GND

GND

LPF_RXI-

LPF_RXI+

LPF_RXQ+

GND

GND

AGC1_V

GND

80

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20

2122 2324 25 2627 282930 313233 3435 36

LPF_TX_PE

LPF_RX_PE

GND

GND

GND

AGC2_BYP-

AGC2_IN-

64656667686970717273747576777879

3738 3940

MOD_TXI+

DEMOD_RXI-

DEMOD_RXI+

DEMOD_RXQ-

DEMOD_RXQ+

GND

AGC2_IN+

6362 61

MOD_TXI-

MOD_TXQ+

AGC2_BYP+

60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41

MOD_TXQ-

AGC2_V

AGC

GND
AGC2_V

CC

AGC2_PE
AGC2_OUT+
AGC2_OUT­AGC2_V

CC

GND
GND
GND
LO_GND
DEMOD_IFIN­DEMOD_IFIN+
MOD_V

CC

LO_OUT
MOD_V

CC

LO_IN
DEMOD_RX_PE
MOD_TX_IF_OUT

MOD_TX_PE

Typical Application Diagram

HFA3424(NOTE)
(FILE# 4131)

HFA3624

RF/IF

CONVERTER

(FILE# 4066)

RFPA

HFA3925

(FILE# 4132)

Foradditionalinformation on the PRISM™ FullDuplexRadio
Chip Set, call [phone] toaccessIntersil’s AnswerFAX
system. When prompted, key in the four-digit document
number (File #) of the data sheets you wish to receive.

VCO

DUAL SYNTHESIZER

HFA3524 (FILE# 4062)

VCO

HFA3766
(FILE# 4328)

÷ 2

QUAD IF MODEM

0o/90

TUNE/SELECT

M

o

U
X

RXI

I

M

RXQ

U
X

VAGC

M
U
X

Q

PRISM™ CHIP SET FILE #4063

TX D OR A

The four-digit file numbers are shown in Typical Application
Diagram, and correspond to the appropriate circuit.

2

Block Diagram

LPF_RXI -

LPF_RXI +

LPF_RXQ +

LPF_RXQ -

DEMOD_RXQ -

DEMOD_RXQ +

DEMOD_RXI -

DEMOD_RXI +

DEDEMOD_IFIN+

DEMOD_IFIN -

AGC2_OUT -

AGC2_OUT +

AGC2_PE

AGC2_IN+

AGC2_IN-

AGC1_OUT -

AGC1_OUT +

AGC1_PE

LPF_SEL1
LPF_SEL0

LPF_TUNE0

LPF_TUNE1
LPF_RX_PE

DEMOD_RX_PE

1000p

33p

10nH

NO FIT

56

56

1000p

DOWN CONV

IF

IF

HFA3766

LPF_RXI_OUT

LPF_RXQ_OUT

-

I

TX D OR A

LPF_TXI_IN

MUX

Q

MUX

o

/90

o

0

÷2

AGC

UP CONVERTER

LPF_TXQ_IN

∑

MUX_LPF

2V

REF

LPF_TX_PE

LPF_TXQ ­LPF_TXQ +
LPF_TXI ­LPF_TXI +

MOD _TXI +
MOD _TXI ­MOD _TXQ +
MOD _TXQ -

MOD_TX_PE

2V REF

AGC1_IN+

SAW

IF

IN

NOTE: VCC, GND and Bypass capacitors not shown.

3

AGC

AGC1_IN-

AGC1_V

VAGC

AGC

AGC2_V

LO_IN

(2XLO)

LO_GND

50Ω

LO_OUT

CC

V

LPF_BYP

1.25V

IF_OUT

MOD_TX

HFA3766

Pin Descriptions

PIN SYMBOL DESCRIPTION

1 AGC1_BYP+ DC feedback pin for AGC amplifier 1. Requires good decoupling and minimum wire length to a solid signal

ground.
2 AGC1_IN+ Non-inverting analog input of AGC amplifier 1.
3 GND Ground. Connect to a solid ground plane.
4 AGC_SEL This pin selects either differential or single ended input configuration for the first stage AGC. Ground this pin for

differential input configuration. Leave it floating for single ended input configuration.
5 AGC1_IN- Inverting analog input of AGC amplifier 1.
6 AGC1_BYP- DC feedback pin for AGC amplifier 1. Requires good decoupling and minimum wire length to a solid signal

ground.

7, 8 GND Ground. Connect to a solid ground plane.

9 LPF_V

10 2V REF Stable 2V reference voltage output for external applications. Loading must be higher than 10kΩ. A bypass

11 LPF_BYP Internal reference bypass pin. This is the common voltage (VCM) used for the LPF digital thresholds. Requires

12 LPF_TXI_IN Low pass filter in phase (I) channel transmit input. Conventional or attenuated direct coupling is required for

13 LPF_TXQ_IN Low pass filter quadrature (Q) channel transmit input. Conventional or attenuated direct coupling is required for

14 LPF_RX_I Low pass filter in phase (I) channel receive output. Requires AC coupling.
15 LPF_RX_Q Low pass filter quadrature (Q) channel receive output. Requires AC coupling.
16 LPF_SEL1 Digitalcontrolinput pins.Selectsfour programmedcut off frequenciesfor thereceive channel. Tuning speedfrom
17 LPF_SEL0

18 LPF_TUNE1 These two pins are used to fine tune the Low pass filter cutoff frequency. A resistor connected between the two
19 LPF_TUNE0

20 TXD or TXA Selects between digital or analog signals. Tie to GND for digital. Tie to VCC for analog.
21 LPF_RX_PE Digital input control pin to enable the LPF receive mode of operation. Enable logic level is High.

CC

Supply pin for the Low pass filter. Use high quality decoupling capacitors right at the pin.

capacitor of at least 0.1µF is required.

0.1µF decoupling capacitor.

digital inputs.

digital inputs

one cutoff to another is less than 1µs.

SEL1 SEL0 CUTOFF FREQUENCY SEl1 SEl0 CUTOFF FREQUENCY

LO LO 2.2MHz HI LO 8.8MHz
LO HI 4.4MHz HI HI 17.6MHz

pins (R

specifications.

) will fine tune both transmit and receive filters. Refer to the tuning equation in the LPF AC

TUNE

22 LPF_TX_PE Digital input control pin to enable the LPF transmit mode of operation. Enable logic level is High.
23 LPF_TXQ- Negative output of the transmit Low pass filter, quadrature channel. ACcoupling is required. Normally connects

to the inverting input of the quadrature Modulator (Mod_TXQ-), pin 40.

24 LPF_TXQ+ Positive output of the transmit Low pass filter, quadrature channel. AC coupling is required. Normally connects

to the non inverting input of the quadrature Modulator (Mod_TXQ+), pin 39.

25 LPF_TXI- Negative output of the transmit Low pass filter, in phase channel. ACcouplingisrequired.Normally connects to

the inverting input of the in phase Modulator (Mod_TXI-), pin 38.

26 LPF_TXI+ Positive output of the transmit Low pass filter, in phase channel. AC coupling is required. Normally connects to

the non inverting input of the in phase Modulator (Mod_TXI+), pin 37.

27 LPF_RXQ- Low pass filter inverting input of the receive quadrature channel. AC coupling is required. This input is normally

coupled to the negative output of the quadrature demodulator (Mod_RXQ-), pin 36.

4