Data Sheet
27448.2
c
8281 AND
8282
LNB SUPPLY AND
CONTROL-VOLTAGE REGULATORS
Always order by complete part number, e.g., A8282SLB .
Intended for analog and digital satellite receivers, these low-noise
block converter regulators (LNBRs) are monolithic linear and switching
voltage regulators specifically designed to provide the power and
interface signals to the LNB down converter via the coaxial cable. If the
device is in standby mode (EN terminal low), the regulator output is
disabled, allowing the antenna down converters to be supplied or
controlled by other satellite receivers sharing the same coaxial cable. In
this mode, the device will limit the output reverse current.
The A8281SLB output is set to 13 or 18-V by the VSEL terminal. It
is supplied in a 16-lead SOIC power-tab package. The power tabs are at
ground potential and need no electrical isolation.
The A8282SLB output is set to 12, 13, 18, or 20-V by the VSEL
terminals. Additionally, it is possible to increase the selected voltage by
1-V to compensate for the voltage drop in the coaxial cable (LLC
terminal high). It is supplied in a 24-lead SOIC power-tab package.
The power tabs are at ground potential and need no electrical isolation.
The A8282SLB is an improved version of the A8283SLB, without a
bypass switch.
ABSOLUTE MAXIMUM RATINGS
at T
A
= +25°C
Supply Voltage, V
IN
........................... 47-V
Output Current, I
LNB
.... Internally Limited
Output Voltage Range, V
LNB
.. -1-V to +22-V
Logic Input Voltage Range,
V
I
................................... -0.3-V to +7-V
Flag Output Voltage, V
OLF
................... 7-V
Operating Temperature Range,
T
A
................................. -20°C to +85°C
Junction Temperature, T
J
................ +150°C
Storage Temperature Range,
T
S
.............................. -55°C to +150°C
FEATURES
a73 LNB selection and standby function
a73 Built-in tone oscillator factory trimmed to 22-kHz, facilitates
DiSEqC™ (a trademark of EUTELSAT) encoding
a73 Tracking switch-mode power converter for lowest dissipation
a73 Externally adjustable short-circuit protection
a73 LNB short-circuit protection and diagnostics
a73 Auxiliary modulation input
a73 Internal over-temperature protection
a73 Reverse-current protection
a73 Cable length compensation (A8282SLB only)
These devices incorporate features that have patents pending.
23
178
1
2
3
4
5
6
7
9
12
16
14
13
24
22
21
20
19
18
11
10
EXTM
VINT
PUMPX
VPUMP
CPUMP
GND
GND
ENT
EN
VSEL0
VSEL1
LLC
NC
OLF
VBULK
NC
NC
GND
GND
SENSE
LNB
LX
VIN
TCAP
CHARGE
PUMP
VOLTAGE CONTROL
REG.
BUCK
Dwg. PP-072-2
15
A8282SLB