4
LT1123
1123fb
All internal circuitry connected to the drive pin is designed
to operate at the saturation voltage of the Darlington
output driver (1.4 to 2V). This allows a resistor to be
inserted between the base of the external PNP device and
the drive pin. This resistor is used to limit the base drive to
the external PNP below the value set internally by the
LT1123, and also to help limit power dissipation in the
LT1123. The operating voltage range of this pin is from
0V to 30V. Pulling this pin below ground by more than one
V
BE
will forward bias the substrate diode of the device.
This condition can only occur if the power supply leads are
reversed and will not damage the device if the current is
limited to less than 200mA.
Feedback Pin (V
FB
): The feedback pin also serves two
functions. It provides a path for the bias current of the
reference and error amplifier and contributes a portion of
the drive current for the Darlington output driver. The sum
total of these currents is the Feedback Pin Bias Current
(300礎 typical). The second function of this pin is to
provide the voltage feedback to the error amplifier.
U
U
PI FU CTIO S
+
5V
CURRENT
LIMIT
THERMAL
LIMIT
GROUND
DRIVE
FB
LT1123 SBD01
SI PLIFIED
BLOCK DIAGRA
FU CTIO AL DESCRIPTIO
U
U
The LT1123 is a 3-pin device designed to be used in
conjunction with a discrete PNP transistor to form an
inexpensive ultralow dropout regulator. The device incor-
porates a trimmed 5V bandgap reference, error amplifier,
a current-limited Darlington driver and an internal thermal
limit circuit. The internal circuitry connected to the drive
pin is designed to function at the saturation voltage of the
Darlington driver. This allows a resistor to be inserted in
series with the drive pin. This resistor is used to limit the
base drive to the PNP and also to limit the power dissipa-
tion in the LT1123. The value of this resistor will be defined
by the operating requirements of the regulator circuit. The
LT1123 is designed to sink a minimum of 125mA of base
current. This is sufficient base drive to form a regulator
circuit which can supply output currents up to 4A at a
dropout voltage of less than 0.75V.
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
LT1248IS#PBF
IC PFC CTRLR AVERAGE CURR 16SOIC
LT1249IS8#PBF
IC PFC CTRLR AVERAGE CURR 8SOIC
LT1577CS-3.3/2.8#TRPBF
IC REG CTRLR DUAL OUT 16SOIC
LT1640HIN8#PBF
IC CONTRLR HOTSWAP NEGVOLT 8-DIP
LT1641IS8#TR
IC CTRLR HOTSWAP POS VOLT 8SOIC
LT1939IDD#TRPBF
IC REG DL BUCK/LINEAR 12DFN
LT3092MPST#TRPBF
IC PROG CURRENT SOURCE SOT223-3
LT3150CGN#TRPBF
IC REG CTRLR SGL POS ADJ 16-SSOP
相关代理商/技术参数
LT1123CZ
功能描述:IC REG CTRLR SGL 5V TO-92-3 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性晶体管驱动器 系列:- 产品培训模块:More Information on LDOs 标准包装:2,500 系列:- 类型:正，固定式 输出数:2 输出电压:2.8V，3.3V 电流 - 电源:12mA 输入电压:5 V ~ 22 V 工作温度:0°C ~ 70°C 封装/外壳:16-SOIC（0.154"，3.90mm 宽） 供应商设备封装:16-SOIC 包装:带卷 (TR)
LT1123CZ#PBF
功能描述:IC REG CTRLR SGL 5V TO-92-3 RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性晶体管驱动器 系列:- 产品培训模块:More Information on LDOs 标准包装:2,500 系列:- 类型:正，固定式 输出数:2 输出电压:2.8V，3.3V 电流 - 电源:12mA 输入电压:5 V ~ 22 V 工作温度:0°C ~ 70°C 封装/外壳:16-SOIC（0.154"，3.90mm 宽） 供应商设备封装:16-SOIC 包装:带卷 (TR)
LT1123CZ#TR
功能描述:IC REG CTRLR SGL 5V TO-92-3 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性晶体管驱动器 系列:- 产品培训模块:More Information on LDOs 标准包装:2,500 系列:- 类型:正，固定式 输出数:2 输出电压:2.8V，3.3V 电流 - 电源:12mA 输入电压:5 V ~ 22 V 工作温度:0°C ~ 70°C 封装/外壳:16-SOIC（0.154"，3.90mm 宽） 供应商设备封装:16-SOIC 包装:带卷 (TR)
LT1123CZ#TRPBF
功能描述:IC REG CTRLR SGL 5V TO-92-3 RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性晶体管驱动器 系列:- 产品培训模块:More Information on LDOs 标准包装:2,500 系列:- 类型:正，固定式 输出数:2 输出电压:2.8V，3.3V 电流 - 电源:12mA 输入电压:5 V ~ 22 V 工作温度:0°C ~ 70°C 封装/外壳:16-SOIC（0.154"，3.90mm 宽） 供应商设备封装:16-SOIC 包装:带卷 (TR)
LT1123CZ2.85
制造商:未知厂家 制造商全称:未知厂家 功能描述:Interface IC
LT1124
制造商:LINER 制造商全称:Linear Technology 功能描述:Dual/Quad Low Noise, High Speed Precision Op Amps
LT1124AC
制造商:LINER 制造商全称:Linear Technology 功能描述:Dual/Quad Low Noise, High Speed Precision Op Amps
LT1124ACN8
功能描述:IC OP-AMP LOW NOISE DUAL 8-DIP RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:73 系列:Over-The-Top® 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:0.07 V/µs 增益带宽积:200kHz -3db带宽:- 电流 - 输入偏压:1nA 电压 - 输入偏移:285µV 电流 - 电源:50µA 电流 - 输出 / 通道:25mA 电压 - 电源，单路/双路(±):2 V ~ 44 V，±1 V ~ 22 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:16-WFDFN 裸露焊盘 供应商设备封装:16-DFN-EP（5x3） 包装:管件