A8508 View Datasheet(PDF) - Allegro MicroSystems
Part Name
Description
MFG CO.
A8508
Allegro MicroSystems
'A8508' PDF : 28 Pages View PDF
A8508
Wide Input Voltage Range, High Efficiency
8-Channel Fault Tolerant LED Driver
ELECTRICAL CHARACTERISTICS1 Valid at VIN = 12 V, TA = 25°C, indicates specifications guaranteed by design and
characterization over the full operating temperature range with TA = TJ = –40°C to 105°C; unless otherwise noted
Characteristics
Symbol
Test Conditions
Min.
Typ.
Max.
Input Voltage Specifications
Operating Input Voltage Range
VIN
9
–
40
UVLO Start Threshold
UVLO Hysteresis
Input Currents
VUVLO(th) VIN rising
VUVLO(hys) VIN falling
−
–
8.5
–
400
–
Input Quiescent Current
IQ
EN = VIH ; fSW = 800 kHz, no load
Input Sleep Supply Current
IQSLEEP VIN = 12 V, EN = FSET/SYNC = 0 V
Input Logic Levels (EN, PWM, MODE, FSET/SYNC)
−
7
−
−
0.5
10.0
Input Logic Level-Low
VIL
9 V < VIN < 40 V
–
–
400
Input Logic Level-High
EN and PWM Pins Pull-Down
Resistor
VIH
9 V < VIN < 40 V
Rpulldown EN, PWM= 5 V
1.5
–
–
−
100
−
MODE Pin Pull-Down Resistor
Error Amplifier
RMODE MODE=2.5 V
−
70
−
Open Loop Voltage Gain
Transconductance
Source Current
Sink Current MODE High
Sink Current MODE Low
COMP Pin Pull-Down Resistor
Soft Start COMP Level
Overvoltage Protection
AVOL
gm
IEA(SRC)
IEA(SINK)H
IEA(SINK)L
RCOMP
VCOMPSS
ΔICOMP = ±10 μA
VCOMP = 1.5 V
VCOMP = 1.5 V, MODE = VIH
VCOMP = 1.5 V, MODE = VIL
¯F¯ ¯A¯U¯¯L¯ ¯T¯ = 0
−
47
−
−
990
−
−
–360
−
−
80
−
−
360
−
−
1.5
−
−
200
−
Overvoltage Threshold
VOVP(th) OVP connected to VOUT
1.11
1.25
1.4
OVP Sense Current
Output Undervoltage Threshold
Boost Switch Gate Driver
IOVPH
VUVP(LOW) Falling
VUVP(HIGH) Rising
45
49
53
−
100
−
−
120
−
Gate Driver Voltage
Driver Pull-up and Pull-down
Resistance
VDRV Measured at GATE pin
RGATEUD Measured at VGATE =VDRV / 2
−
7
−
−
4.5
−
Driver to Ground Resistance
Sense Positive
Secondary Sense Positive
RGATEG EN = 0, VIN = 0
VSENSEP
VSENSESEC
−
200
−
85
100
115
−
165
−
Unit
V
V
mV
mA
μA
mV
V
kΩ
kΩ
dB
μA/V
μA
μA
μA
kΩ
mV
V
μA
mV
mV
V
Ω
kΩ
mV
mV
Continued on the next page…
Allegro MicroSystems, Inc.
5
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
Share Link: 