12

DS641F2

CS8421

DIGITAL FILTER CHARACTERISTICS

3.

The equation for the group delay through the sample-rate converter is (56.581 / Fsi) + (55.658 / Fso).

For example, if the input sample rate is 192 kHz and the output sample rate is 96 kHz, the group delay

through the sample-rate converter is (56.581/192,000) + (55.658/96,000) =.875 milliseconds.

DC ELECTRICAL CHARACTERISTICS

(GND = 0 V; all voltages with respect to 0 V.)

4.

Power Down Mode is defined as RST = LOW with all clocks and data lines held static, except when a

crystal is attached across XTI-XTO, in which case the crystal will begin oscillating.

5.

Normal operation is defined as RST = HI.

Parameter

Min

Typ

Max

Units

Passband (Upsampling or Downsampling)

-

-

0.4535*Fso

Hz

Passband Ripple

-

-

±0.007

dB

Stopband

0.5465*Fso

-

-

Hz

Stopband Attenuation

125

-

-

dB

Group Delay

(Note 3)

ms

Parameters

Symbol

Min

Typ

Max

Units

Power-Down Mode (Note 4)

Supply Current in power-down

VD

(Oscillator attached to XTI-XTO)

VL = 3.3 V

VL = 5.0 V

50

100

200

μA

μA

μA

Supply Current in power-down

VD

(Crystal attached to XTI-XTO)

VL = 3.3 V

VL = 5.0 V

100

1.5

4

μA

mA

mA

Normal Operation (Note 5)

Supply Current at 48 kHz Fsi and Fso

VD

(Oscillator attached to XTI-XTO)

VL = 3.3 V

VL = 5.0 V

24

2.5

4

mA

mA

mA

Supply Current at 192 kHz Fsi and Fso

VD

(Oscillator attached to XTI-XTO)

VL = 3.3 V

VL = 5.0 V

80

8

13

mA

mA

mA

Supply Current at 48 kHz Fsi and Fso

VD

(Crystal attached to XTI-XTO)

VL = 3.3 V

VL = 5.0 V

24

3

7

mA

mA

mA

Supply Current at 192 kHz Fsi and Fso

VD

(Crystal attached to XTI-XTO)

VL = 3.3 V

VL = 5.0 V

80

4

6.5

mA

mA

mA