LT3474/LT3474-1
PIN FUNCTIONS
DNC (Pins 1, 16): Do not connect external circuitry to these
pins, or tie them to GND. Leave the DNC pins ?oating.
OUT (Pin 2): The OUT pin is the input to the current sense
resistor. Connect this pin to the inductor and the output
capacitor.
LED (Pin 3): The LED pin is the output of the current sense
resistor. Connect the anode of the LED here.
V IN (Pin 4): The V IN pin supplies current to the internal
circuitry and to the internal power switch and must be
locally bypassed.
SW (Pin 5): The SW pin is the output of the internal power
switch. Connect this pin to the inductor and switching
diode.
BOOST (Pin 6): The BOOST pin is used to provide a drive
voltage, higher than the input voltage, to the internal bipolar
NPN power switch.
BIAS (Pin 7): The BIAS pin connects through a Schottky
diode to BOOST. Tie to OUT.
GND (Pins 8, 15, Exposed Pad Pin 17): Ground. Tie both
GND pins and the Exposed Pad directly to the ground
plane. The Exposed Pad metal of the package provides both
electrical contact to ground and good thermal contact to
the printed circuit board. It must be soldered to the circuit
SHDN (Pin 10): The SHDN pin is used to shut down the
switching regulator and the internal bias circuits. The
2.6V switching threshold can function as an accurate
under-voltage lockout. Pull below 0.3V to shut down the
LT3474/LT3474-1. Pull above 2.65V to enable the LT3474/
LT3474-1. Tie to V IN if the SHDN function is unused.
REF (Pin 11): The REF pin is the buffered output of the
internal reference. Either tie the REF pin to the V ADJ pin for
a 1A output current, or use a resistor divider to generate a
lower voltage at the V ADJ pin. Leave this pin unconnected
if unused.
V C (Pin 12): The V c pin is the output of the internal error
amp. The voltage on this pin controls the peak switch
current. Use this pin to compensate the control loop.
V ADJ (Pin 13): The V ADJ pin is the input to the internal
voltage to current ampli?er. Connect the V ADJ pin to the
REF pin for a 1A output current. For lower output cur-
rents, program the V ADJ pin using the following formula:
I LED = 1A ? V ADJ /1.25V.
PWM (Pin 14): The PWM pin controls the connection of
the V C pin to the internal circuitry. When the PWM pin is
low, the V C pin is disconnected from the internal circuitry
and draws minimal current. If the PWM feature is unused,
leave this pin unconnected.
board for proper operation.
R T (Pin 9): The R T pin is used to set the internal oscilla-
tor frequency. Tie an 80.6k resistor from R T to GND for a
500kHz switching frequency.
3474fd
6
相关PDF资料
LT3475EFE-1#PBF IC LED DRVR HP CONS CURR 20TSSOP
LT3476EUHF#PBF IC LED DRVR HP CONST CURR 38-QFN
LT3477EFE#PBF IC LED DRVR HP CONS CURR 20TSSOP
LT3478IFE#PBF IC LED DRVR HP CONS CURR 16TSSOP
LT3486EFE#PBF IC LED DRVR WHITE BCKLGT 16TSSOP
LT3491EDC#TRMPBF IC LED DRIVER WHITE BCKLGT 6-DFN
LT3492IFE#TRPBF IC LED DVR HP CONST CURR 28TSSOP
LT3496IUFD#PBF IC LED DRVR WHT/RGB BCKLT 28-QFN
相关代理商/技术参数
LT3474IFE#TRPBF 功能描述:IC LED DRVR HP CONS CURR 16TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极,PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LT3474IFE-1 制造商:LINER 制造商全称:Linear Technology 功能描述:True Color PWM Delivers Constant Color with 400:1 Dimming Range
LT3474IFE-1#PBF 功能描述:IC LED DRVR HP CONS CURR 16TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极,PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LT3474IFE-1#TRPBF 功能描述:IC LED DRVR HP CONS CURR 16TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极,PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LT3474IFE-1-PBF 制造商:LINER 制造商全称:Linear Technology 功能描述:Step-Down 1A LED Driver
LT3474IFE-1-TRPBF 制造商:LINER 制造商全称:Linear Technology 功能描述:Step-Down 1A LED Driver
LT3474IFE-PBF 制造商:LINER 制造商全称:Linear Technology 功能描述:Step-Down 1A LED Driver
LT3474IFE-TRPBF 制造商:LINER 制造商全称:Linear Technology 功能描述:Step-Down 1A LED Driver