|
|
|
부품번호 | A8514 기능 |
|
|
기능 | High Efficiency Fault Tolerant LED Driver | ||
제조업체 | Allegro | ||
로고 | |||
전체 30 페이지수
A8514
Wide Input Voltage Range, High Efficiency
Fault Tolerant LED Driver
Features and Benefits
• AEC-Q100 Qualified
• Wide input voltage range of 5 to 40 V for start/stop, cold
crank and load dump requirements
• Fully integrated LED current sinks and boost converter
with 60 V DMOS
• Sync function to synchronize boost converter switching
frequency up to 2.3 MHz, allowing operation above the
AM band
• Excellent input voltage transient response
• Single resistor primary OVP minimizes VOUT leakage
• Internal secondary OVP for redundant protection
• LED current of 80 mA per channel
• Drives up to 12 series LEDs in 4 parallel strings
• 0.7% to 0.8% LED to LED matching accuracy
• PWM and analog dimming inputs
• 5000:1 PWM dimming at 200 Hz
• Provides driver for external PMOS input disconnect switch
• Extensive protection against:
▫ Shorted boost switch or inductor
▫ Shorted FSET or ISET resistor
▫ Shorted output
▫ Open or shorted LED pin
▫ Open boost Schottky
▫ Overtemperature (OTP)
Package: 20-pin TSSOP with exposed
thermal pad (suffix LP)
Not to scale
Description
The A8514 is a multi-output white LED driver for small-size
LCD backlighting. It integrates a current-mode boost converter
with internal power switch and four current sinks. The boost
converter can drive up to 48 LEDs, 12 LEDs per string, at
80 mA. The LED sinks can be paralleled together to achieve
even higher LED currents, up to 320 mA. The A8514 can
operate with a single power supply, from 5 to 40 V, which
allows the part to withstand load dump conditions encountered
in automotive systems.
TheA8514 can drive an external P-FET to disconnect the input
supply from the system in the event of a fault. The A8514
provides protection against output short and overvoltage,
open or shorted diode, open or shorted LED pin, shorted
boost switch or inductor, shorted FSET or ISET resistor, and
IC overtemperature. A dual level cycle-by-cycle current limit
function provides soft start and protects the internal current
switch against high current overloads.
The A8514 has a synchronization pin that allows PWM
switching frequencies to be synchronized in the range of
580 kHz to 2.3 MHz. The high switching frequency allows
the A8514 to operate above the AM radio band.
Continued on the next page…
Applications:
LCD backlighting or LED lighting for:
▫ Automotive infotainment
▫ Automotive cluster
▫ Automotive center stack
8 toVI1N6 V
4.C7INμF
50 V
VC
100 kΩ
Typical Application Circuit
RSC
0.033 Ω
RADJ
249 Ω
2R0CΩ
Optional
22CCnF
Q1
CVDD
0.1 μF
RISET
8.25 kΩ
RFSET
10 kΩ
L1
10 μH
D1
2 A / 60 V
GATE
SW
VSENSE
VIN A8514
VDD
PAD
FAULT
PWM/EN
APWM
ISET
FSET/SYNC
OVP
LED1
LED2
LED3
LED4
COMP
AGND PGND
13R7OkVΩP
CP
120 pF
VOUT
COUT
4.7 μF
50 V
RZ
150 Ω
CZ
0.47 μF
Figure 1. Application with VIN to ground short protection, using optional P-MOSFET for input disconnect protection
A8514-DS, Rev. 5
A8514
Wide Input Voltage Range, High Efficiency
Fault Tolerant LED Driver
Functional Block Diagram
VIN
FSET/SYNC
COMP
VSENSE
GATE
PWM/EN
APWM
ISET
VDD
Regulator
UVLO
Internal VCC
Oscillator
Internal VCC
1.235 V
Ref
VREF
AGND
∑+
–
SW
Fault
Driver
Circuit
Diode
Open
+ Sense
–
Internal
Soft Start
+
ISS
–
Input Current
Sense Amplifier
IADJ
Current
Sense
Fault
PMOS
Driver
GOFF
Enable
100 kΩ
PWM
VREF
Internal VCC
ISET
Fault
ISS
LED
Driver
PGND
Thermal
Shutdown
OVP
Sense
VREF
Open/Short
LED Detect
AGND
Fault
OVP
LED1
LED2
LED3
LED4
FAULT
PAD
PGND
AGND
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
4
4페이지 A8514
Wide Input Voltage Range, High Efficiency
Fault Tolerant LED Driver
ELECTRICAL CHARACTERISTICS1,2 (continued) Valid at VIN = 16 V, TA = 25°C, indicates specifications guaranteed by design
and characterization over the full operating temperature range with TA = TJ = –40°C to 125°C; unless otherwise noted
Characteristics
Symbol
Test Conditions
Min.
Typ.
Max.
Unit
GATE Pin
GATE Pin Sink Current
Gate Fault Shutdown Greater than
2X Current2
IGSINK
tGFAULT2
VGS = VIN
− −104 −
−−3
μA
μs
Gate Fault Shutdown Greater than
1–2X Current
tGFAULT1
−
10,000
−
fSW
cycles
Gate Voltage
VGS
Gate to source voltage measured when gate
is on
− –6.7 −
V
VSENSE Pin
VSENSE Pin Sink Current
VSENSE Trip Point
VSENSE 2X Trip2
¯F¯¯A¯¯U¯¯L¯¯T¯ Pin
IADJ
VSENSEtrip1
VSENSEtrip2
Measured between VIN and VSENSE,
RADJ = 0 Ω
2X VSENSEtrip , instantaneous shutdown,
RADJ = 0 Ω
18.8 20.3 21.8
94 104 114
− 180 −
μA
mV
mV
¯F¯¯A¯U¯¯L¯¯T¯ Pull-Down Voltage
¯F¯¯A¯U¯¯L¯¯T¯ Pin Leakage Current
Thermal Protection (TSD)
VFAULT
IFAULTLKG
IFAULT = 1 mA
VFAULT = 5 V
− − 0.5 V
− − 1 μA
Thermal Shutdown Threshold2
TSD Temperature rising
− 165 −
ºC
Thermal Shutdown Hysteresis2
TSDHYS
− 20 − ºC
1For input and output current specifications, negative current is defined as coming out of the node or pin (sourcing); positive current is defined as
going into the node or pin (sinking).
2Ensured by design and characterization, not production tested.
3Minimum VIN = 5 V is only required at startup. After startup is completed, the IC is able to function down to VIN = 4 V.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
7
7페이지 | |||
구 성 | 총 30 페이지수 | ||
다운로드 | [ A8514.PDF 데이터시트 ] |
당사 플랫폼은 키워드, 제품 이름 또는 부품 번호를 사용하여 검색할 수 있는 |
구매 문의 | 일반 IC 문의 : 샘플 및 소량 구매 ----------------------------------------------------------------------- IGBT, TR 모듈, SCR 및 다이오드 모듈을 포함한 광범위한 전력 반도체를 판매합니다. 전력 반도체 전문업체 상호 : 아이지 인터내셔날 사이트 방문 : [ 홈페이지 ] [ 블로그 1 ] [ 블로그 2 ] |
부품번호 | 상세설명 및 기능 | 제조사 |
A8510 | High Efficiency Fault Tolerant LED Driver | Allegro |
A8512 | LED Backlight Driver | Allegro Micro Systems |
DataSheet.kr | 2020 | 연락처 | 링크모음 | 검색 | 사이트맵 |