a8292 Allegro MicroSystems, Inc., a8292 Datasheet - Page 13

• Manufacturer Part Number: a8292
• Description: Dual Lnb Supply And Control Voltage Regulator
• Manufacturer: Allegro MicroSystems, Inc.

A8292
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Table 3. Control Registers with Address (I1, I0) = 10 and 11
Bit
TMODEx ToneMode. Selects between the use of an external 22 kHz logic signal or the use
TGATEx Tone Gate. Allows either the internal or external 22 kHz tone signals to be gated,
CADTx
–
–
–
I0
I1
0
1
2
3
4
5
6
7
(Address: I1, I0 = 10)
of the internal 22 kHz oscillator to control the tone generation on the LNBx output.
A 0 selects the external tone and a 1 selects the internal tone. See the Tone Genera-
tion section for more information
unless the EXTMx is selected for gating. When set to 0, the selected tone (via
TMODEx) is off. When set to 1, the selected tone is on. See Tone Generation Sec-
tion for more information.
Cable Disconnect Test. To perform this test, set bits CADT, ENB, and VSEL0
through VSEL3 through the I
linear regulator is disabled, a 1 mA current source between the BOOST output and
the LNB output is enabled, and the BOOST voltage is increased to 22.8 V. After
these conditions are set, if the LNB voltage is above 21 V, it is assumed that the
coaxial cable connection between the LNBR output and the LNB head has been
disconnected. In this case, the CAD bit is set in the Status register. If there is a load
on the LNB pin, then the LNB voltage will decrease proportionally to the load
current. If the LNB volts drop below 19.95 V, it is assumed that the coaxial cable is
connected and the CAD bit in the Status register is set to 0.
Not Used.
Not Used.
Not Used.
Address.
Address.
Dual LNB Supply and Control Voltage Regulator
Channel 1
TMODE1
TGATE1
CADT1
I0
I1
–
–
–
Name
(Address: I1, I0 = 11)
Channel 2
TMODE2
TGATE2
CADT2
2
C-compatible interface. During this test, the LNB
I0
I1
–
–
–
Address Bit
Channel 1: 0
Channel 2: 1
Address Bit
Channel 1: 1
Channel 2: 1
0: External Tone
1: Internal Tone
0: Tone Gated Off
1: Tone Gated On
0: Cable Disconnect Test Off
1: Cable Disconnect Test On
Not Used
Not Used
Not Used
Setting
115 Northeast Cutoff, Box 15036
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 [phone]
www.allegromicro.com
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