a8292 Allegro MicroSystems, Inc., a8292 Datasheet - Page 12

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

A8292
Control Registers
All main functions of the A8292 are controlled through the
I
A8292 contains numerous control options, as well as featuring
two channels, it is necessary to have four Control registers. Each
2
C™-compatible interface via the 8-bit Control registers. As the
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Table 2. Control Registers with Address (I1, I0) = 00 and 01
Bit
0
1
2
3
4
5
6
7
VSEL
VSEL
VSEL
VSEL
ODTx
ENBx
I0
I1
(Address: I1, I0 = 00)
(I
2
Channel 1
3
0
1
2
x
C™-Compatible Write Register)
x
x
x
VSEL
VSEL
VSEL
VSEL
ODT1
ENB1
I0
I1
These three bits provide incremental control over the voltage on the LNBx output.
The available voltages provide the necessary levels for all the common standards
plus the ability to add line compensation in increments of 333 mV. The voltage levels are
defined in table 4, Output Voltage Amplitude Selection.
Switches between the low level and high level output voltages on the LNBx output. 0 selects
the low level voltage and 1 selects the high level. The low-level center voltage is 12.709 V
nominal and the high level is 18.042 V nominal. These may be increased in steps of 333 mV
using the VSEL
The overcurrent disable timers are always enabled.
Enables the LNBx output. When set to 1 the LNBx output is switched on. When set to 0,
the LNBx output is disabled.
Address
Address
0
2
3
1
1
1
1
1
Dual LNB Supply and Control Voltage Regulator
Name
(Address: I1, I0 = 01)
2
x, VSEL
Channel 2
VSEL
VSEL
VSEL
VSEL
ODT2
ENB2
1
I0
I1
x and VSEL
0
1
2
3
2
2
2
2
0
x control register bits.
register contains up to 6 bits of data (bit 0 to bit 5), followed by 2
bits for the register address (bit 6 and bit 7). The power-up states
for the control functions are all 0s.
and the settings for output voltage:
See table 4, Output Voltage Amplitude Selection
0: LNBx = Low range
1: LNBx = High range
1 (recommended): The ODT functions are always
enabled, but setting 1 recommended at all times.
0: Disable LNBx Output
1: Enable LNBx Output
Address Bit
Channel 1: 0
Channel 2: 1
Address Bit
Channel 1: 0
Channel 2: 0
The following tables define the control bits for each address
Setting
115 Northeast Cutoff, Box 15036
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 [phone]
www.allegromicro.com
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