Zetex ZXF36L01W24, ZXF36L01W24TC Datasheet

VARIABLE Q FILTER

ZXF36L01

DESCRIPTION

The ZXF36L01 is a versatile analog high Q bandpass
filter. The device contains two sections:

1 Variable Q bandpass filter.
2 Mixer block.

The basic filter section requires 2 resistors and 2
capacitors to set the centre frequency. The filter
operates up to a frequency of 150kHz. Two external
resistors control filter Q Factor. The Q can be varied up
to 50.

The mixer is includedto extend thefrequency range up
to 700kHz and to permit the centre frequency to be
tuned. The local oscillator can be any waveform,
making microprocessor control convenient.

SYSTEM DIAGRAM

APPLICATIONS

Many filter applications including: -

Audio bandpass and notch

•

Micro controlled frequency

•

Adaptive filtering

•

Sonar and Ultrasonic Systems

•

Instrumentation

•

FEATURES AND BENEFITS

Centre Frequency up to 700kHz

•

Tuneable centre frequency

•

Variable Q

•

Low power

•

• Standby mode for improved battery life

ORDERING INFORMATION

PART NUMBER PACKAGE PART

ZXF36L01W24 SO24W ZXF36L01

PART NUMBER CONTAINER INCREMENT

ZXF36L01W24TC Reel 13”

330mm

ZXF36L01W24 Tube 31

MARK

1000

ISSUE 3 - JANUARY 2002

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ZXF36L01

ABSOLUTE MAXIMUM RATINGS

Voltage on any pin 7.0V (relative to Vss)
Operating temperature range 0 to 70°C (de-rated for -40 to 85ºC)
Storage temperature -55 to 125°C

ELECTRICAL CHARACTERISTICS

Test Coνditions: Temperature =25°C, V

GENERAL CHARACTERISTICS
Parameter Conditions Min. Typical Max. Units

Operating current PD=V
Shutdown current PD
IIH (PD)
IIL (PD)

FILTER CHARACTERISTICS

Max. operating frequency 150 kHz
Q usable range 0.5 50
Centre frequency temperature

coefficient
Average Q temperature

coefficient
Voltage noise 1 – 100 kHz 20
Input impedance 30 50
Max. output swing
Output sink current 150
Output source current 150

MIXER CHARACTERISTICS

Max. operating frequency 700 kHz
Maximum signal input 300 mV pk-pk
Maximum Local Oscillator input 100 mV pk-pk
Minimum Local Oscillator input 5 mV pk-pk
Local Oscillator input Impedance 60

=V
VIH =5V (WRT VSS)1.0µA
VIL =0V (WRT VSS) -1.0 µA

Q=30, fo = 1kHz
Note 1

Q=30, fo = 1kHz
Note 2

Output load ≥10 kΩ

= 5.00V, VSS= 0.00V

DD

DD

SS

2.2 3.4 4.5 mA
160 300 µA

10 ppm/°C

0.1 % /°C

nV/√ Hz
kΩ

1.6 V pk-pk

µA
µA

Ω

NOTE 1
Centre frequency temperature coefficient is dominated by the external R & C components. On chip drift is
negligable.

Note 2
Average Q temperature coefficient is dominated by the external R components.

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ZXF36L01

TYPICAL ELECTRICAL CHARACTERISTICS

Test Coνditions:V

TypicalGainatFoVQFactor

50

45

40

35

Gai n (d B)

30

25

20

10 20 30 40 50 60 70 80 90 100

Q Factor

(Fo = 140 KHz)

= 5.00V, VSS= 0.00V

DD

Q Factor V Frequency

32

30

28

26

24

QFactor

22

20

18

16

0 20 40 60 80 100 120 140 160 180 200

Frequency (kHz)

Gain at fo describes the peak gain of
the notch pass filter. This gain is
defined by the value of Q Factor.

The curve shows Q Factor over
frequency for a fixed loop gain
(Rf/Ri).

ISSUE 3 - JANUARY 2002

Components used: 1/8 watt metal
film resistors (+/- 50 ppm). Ceramic
capacitors (+/- 50 ppm).

3

ZXF36L01

DESCRIPTION OF PIN FUNCTIONS

V

DD

V

SS

BG Bias Generator output. To be decoupled with a 100nF capacitor to V

BI Bias inputs for internal circuitry, both to be connected to BG.

PD

FI1,Fl2 Filter input, FI1 or FI2 depending on filter configuration.

FO Filter output for all configurations.

LO Local Oscillator signal input.

MXI Mixer signal input.

MXO Mixer signal output.

C1, RC1 Phase advance network nodes. Values R and C set centre frequency, fo.

R2, RC2 Phase retard network nodes. Values R and C set centre frequency, fo.

GP1,2,3 Loop gain programming nodes.

CONNECTION DIAGRAM

Positive supply connection (5 volts). Both pins to be connected.
To be decoupled with a 100nF capacitor to V

SS

.

Negative supply connection; system ground (0 volts). Both pins to be connected.

SS

(or external supply referenced to V

Active low. This feature can be used to reduce power consumption for applications that
have a standby mode.

SS

)

.

V

1

SS

FI1
C1

RC1
R2

BI
MXO

RC2
GP1
GP2
GP3
V

SS

V

FI2

MXI

BG
N/C
N/C
N/C

V

DD

FO

LO
BI

PD

DD

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