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Typical operating characteristics (continued) – Rainbow Electronics MAX7491 User Manual

Page 7

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MAX7490/MAX7491

Dual Universal Switched-Capacitor Filters

_______________________________________________________________________________________

7

-20

-120

1k

10k

MAX7490

THD + NOISE vs. FREQUENCY

MAX7490-13

INPUT FREQUENCY (Hz)

THD + NOISE (dB)

-30

-40

-50

-60

-70

-80

-90

-100

-110

B

A

A = MODE 1
B = MODE 3

-90

-80

-70

-60

-50

-40

-30

-20

-10

0

1.0

0.5

1.5

2.0

2.5

3.0

MAX7491

THD + NOISE vs. INPUT VOLTAGE

MAX7490-14

INPUT VOLTAGE (Vp-p)

THD + NOISE (dB)

B

A

A = MODE 1
B = MODE 3

-90

-80

-70

-60

-50

-40

-30

-20

-10

0

1

2

3

4

5

MAX7490

THD + NOISE vs. INPUT VOLTAGE

MAX7490-15

INPUT VOLTAGE (Vp-p)

THD + NOISE (dB)

B

A

A = MODE 1
B = MODE 3

2.0

3.0

2.5

3.5

4.0

4.5

5.0

0

8

4

12

16

20

OUTPUT VOLTAGE SWING vs. R

LOAD

MAX7490-16

R

LOAD

(k

Ω) TO COM

OUTPUT SWING (Vp-p)

V

DD

= 5V

V

DD

= 3V

0

500

1500

1000

2000

2500

0

400

200

600

800

1000

INTERNAL OSCILLATOR PERIOD

vs. SMALL CAPACITANCE

MAX7490-17

CAPACITANCE (pF)

INTERNAL OSCILLATOR FREQUENCY (kHz)

V

DD

= 3V

V

DD

= 5V

0

20

40

60

80

100

120

140

160

1

3

2

4

5

6

7

INTERNAL OSCILLATOR PERIOD

vs. LARGE CAPACITANCE

MAX7490-18

CAPACITANCE (nF)

INTERNAL OSCILLATOR FREQUENCY (kHz)

V

DD

= 5V

V

DD

= 3V

126

128

127

130

129

132

131

133

3.0

4.0

3.5

4.5

5.0

5.5

INTERNAL OSCILLATOR FREQUENCY

vs. SUPPLY VOLTAGE

MAX7490-19

V

DD

(V)

INTERNAL OSCILLATOR FREQUENCY (kHz)

C

OSC

= 1000pF

124

130

128

126

132

134

136

138

140

142

144

-40

10

-15

35

60

85

INTERNAL OSCILLATOR FREQUENCY

vs. TEMPERATURE

MAX7490-20

TEMPERATURE (

°C)

INTERNAL OSCILLATOR FREQUENCY (kHz)

V

DD

= 3V

V

DD

= 5V

C

OSC

= 1000pF

Typical Operating Characteristics (continued)

(V

DD

= +5V for MAX7490, V

DD

= +3V for MAX7491, f

CLK

= 625kHz, SHDN = EXTCLK = V

DD

, COM = V

DD

/2, Mode 1, R3 = R1 = 50k

Ω,

R2 = 10k

Ω, Q = 5, T

A

= +25°C, unless otherwise noted.)