|
|
PDF AT9919 Data sheet ( Hoja de datos )
| Número de pieza | AT9919 | |
| Descripción | Hysteretic Buck High-Brightness LED Driver | |
| Fabricantes | Microchip | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de AT9919 (archivo pdf) en la parte inferior de esta página. Total 16 Páginas | ||
|
No Preview Available !
AT9919
Hysteretic Buck High-Brightness LED Driver with High-Side Current Sensing
Features
• Hysteretic Control with High-side Current Sensing
• Wide Input Voltage Range: 4.5V to 40V
• >90% Efficiency
• Typical ±5% LED Current Accuracy
• Up to 2 MHz Switching Frequency
• Adjustable Constant LED Current
• Analog or Pulse-With Modulation (PWM) Control
Signal for PWM Dimming
• Overtemperature Protection
• –40ºC to +125ºC Operating Temperature Range
Applications
• LED Lighting Applications
General Description
The AT9919 is a PWM controller IC designed to drive
high-brightness LEDs using a buck topology. It
operates from an input voltage of 4.5 VDC to 40 VDC
and employs hysteretic control with a high-side current
sense resistor to set the constant output current.
The operating frequency range can be set by selecting
the proper inductor. Operation at high switching
frequency is possible since the hysteretic control
maintains accuracy even at high frequencies. This
permits the use of small inductors and capacitors,
minimizing space and cost in the overall system.
LED brightness control is achieved with PWM dimming
from an analog or PWM input signal. Unique PWM
circuitry allows true constant color with a high dimming
range. The dimming frequency is programmed using a
single external capacitor.
The AT9919 comes in a small, 8-lead DFN package
and is qualified for LED lighting applications.
Package Type
8-lead DFN
(Top View)
CS 1
VIN 2
RAMP 3
ADIM 4
See Table 2-1 for pin information.
GND
8 GATE
7 GND
6 VDD
5 DIM
2016 Microchip Technology Inc.
DS20005595A-page 1
1 page  
AT9919
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Specifications: VIN = 12V, VDIM = VDD, VRAMP = GND, CVDD = 1 µF, RCS = 0.5Ω, TA = TJ = –40ºC to
+125ºC (Note 1) unless otherwise noted.
Parameter
Sym.
Min. Typ. Max.
GATE DRIVER
GATE Current, Source
GATE Current, Sink
IGATE
0.3 0.5 —
0.7 1 —
GATE Output Rise Time
TRISE
GATE Output Fall Time
TFALL
GATE High Output Voltage
VGATE(HI)
GATE Low Output Voltage
VGATE(LO)
OVERTEMPERATURE PROTECTION
—
—
VDD – 0.5
—
40
17
—
—
55
25
—
0.5
Over Temperature Trip Limit
TOT
Temperature Hysteresis
∆THYST
ANALOG CONTROL OF PWM DIMMING
128 140 —
— 60 —
Dimming Frequency
fRAMP
130 — 300
550 — 1250
RAMP Threshold, Low
VLOW
—
RAMP Threshold, High
VHIGH
1.8
ADIM Offset Voltage
VOS –35
Note 1: Limits obtained by design and characterization.
0.1
—
—
—
2.1
+35
2: For design guidance only
Unit
A
A
ns
ns
V
V
ºC
ºC
Hz
V
V
mV
Conditions
VGATE = GND (Note 2)
VGATE = VDD (Note 2)
CGATE = 2 nF
CGATE = 2 nF
IGATE = 10 mA
IGATE = –10 mA
Note 2
Note 2
CRAMP = 47 nF
CRAMP = 10 nF
TEMPERATURE SPECIFICATIONS
Parameter
Sym.
TEMPERATURE RANGE
Operating Temperature
Junction Temperature
Storage Temperature
PACKAGE THERMAL RESISTANCE
8-lead DFN
TA
TJ
TS
JA
Min.
–40
—
–65
—
Typ.
—
—
—
+37
Max. Unit
+125
+150
+150
°C
°C
°C
— °C/W
Conditions
2016 Microchip Technology Inc.
DS20005595A-page 5
5 Page 
AT9919
Note: For the most current package drawings, see the Microchip Packaging Specification at www.microchip.com/packaging.
2016 Microchip Technology Inc.
DS20005595A-page 11
11 Page | ||
| Páginas | Total 16 Páginas | |
| PDF Descargar | [ Datasheet AT9919.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| AT9910 | 1A Low Dropout Regulator |  Global Mixed-mode Technology |
| AT9911 | 1A Low Dropout Regulator | Global Mixed-mode Technology |
| AT9915 | 1.5A Low Dropout Regulator | Global Mixed-mode Technology |
| AT9915 | 1.5A Low Dropout Regulator | Global Mixed-mode Technology |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |