A8287 ALLEGRO [Allegro MicroSystems], A8287 Datasheet - Page 3

• Manufacturer Part Number: A8287
• Description: LNB Supply and Control Voltage Regulator
• Manufacturer: ALLEGRO [Allegro MicroSystems]

ELECTRICAL CHARACTERISTICS at T
Continued on next page
Set-point Accuracy, load and line
regulation
Supply Current
Boost Switch-On Resistance
Switching Frequency
Switch Current Limit
Linear Regulator Voltage Drop
Slew Rate Current on TCAP
Output Voltage Slew Period
Output Reverse Current
Ripple and Noise on LNB Output
Protection Circuitry
Overcurrent Limit
Overcurrent Disable Time
V
V
Power-Not-Good Flag Set
Power-Not-Good Flag Reset
Thermal Shutdown Threshold
Thermal Shutdown Hysteresis
IN
IN
Turn-On Threshold
Undervoltage Threshold
Characteristics
Symbol
R
PNG
PNG
∆V
UV
UV
DSBOOST
I
V
I
t
V
∆T
CCEN
I
I
I
t
CAP
slew
T
fo
OR
LIM
DIS
CC
–
RN
O1
REG
OFF
J
ON
reset
J
set
A
Relative to target voltage selected, with:
I
ENB = Low, LNB output disabled
ENB = High, LNB output enabled, I
T
–
V
V
Charging
Discharging
V
ENB = Low, V
See notes 1 and 2
High limit
Low limit
–
Guaranteed turn-off
Guaranteed turn-on
–
–
See note 1
See note 1
= +25°C, V
LOAD
J
IN
BOOST
LNB
= 25 °C, I
= 12 V
= 13 to 18 V, TCAP = 6.8 nF, I
= 0 to 500 mA
LNB Supply and Control Voltage Regulator
– V
www.allegromicro.com
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 [phone]
LNB
LOAD
, no tone signal, I
IN
LNB
= 10 to 16 V (unless otherwise noted)
Test Conditions
= 500mA
= 28 V with C4 fully charged
LOAD
= 500 mA
LOAD
LOAD
= 500 mA
= 0mA
A8285/A8287
–12.5
Min.
8.65
8.75
-4.5
320
400
550
400
2.0
7.5
1.2
77
82
–
–
–
–
–
–
–
–
Typ.
9.15
9.25
400
352
600
–10
500
700
500
165
10
85
90
20
0
–
–
3
1
–
–
Max.
–7.5
12.5
9.65
9.75
500
384
800
850
600
4.5
4.0
1.7
15
50
93
98
7
–
5
–
–
%V
%V
Units
mV
kHz
mΩ
mA
mA
mV
mA
mA
mA
ms
µA
µA
µs
°C
°C
%
A
V
V
LNB
LNB
pp
3