9

Supertex inc.

www.supertex.com

MD3872

Doc.# DSFP-MD3872

B060413

ADDR=7 D[6]

PDC Enable External Biasing

0

Disable external Biasing for VGA

1

Enable external Biasing for VGA

ADDR=7 D[5]

FLEX AAF Tracking Auto-Tuning Control

0

FLEX = 0 disable continuous auto-tuning for AAF tracking the input clock.

1

FLEX=1 enable continuous auto-tuning for AAF tracking the input clock,

Note:

FLEX must be set to “1” first then to “0” to turn off the AFF auto-tracking after the chip power on, although the power-

on default is FLEX = 0.

ADDR=7 D[3]

SWLNA LNA Gain Switches Control

0

SW1~8 Off, disconnecting R

1

SWLNA=1 On, connecting R

ADDR=7 D[2]

GAINLNA LNA Gain Control

0

LNA gain set to 18dB

1

LNA gain set to 14dB

ADDR=7 D[1:0]

PG[1:0] Gain Setting

00

Select 23.5dB Gain Setting

01

Select 29.0dB Gain Setting

10

Select 34.5dB Gain Setting

11

Select 40.0dB Gain Setting

ADDR=8 D[9]

CTL AAF Frequency Programming Enable

0

AAF use AAF[5:2] tracking the sampling frequency.

1

AAF use PR[5:2] programmed frequency.

Note:

See AAF and PR tables

ADDR=7 D[9:8]

AAF[1:0] Cutoff Frequency and Control Table

AAF[1:0]

3rd Order Anti-Aliasing Filter Corner Freq fAAF

Min

Typ

Max

Units

Note

00

6.6

FS/3

15

MHz

100% as default

01

115

%

% of default

10

Set by AAF[5:2]

MHz

11

85

%

% of default