Datasheet LT3150 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Fast Transient Response, Low Input Voltage, Very Low Dropout Linear Regulator Controller |
| Pages / Page | 20 / 1 — FEATURES. DESCRIPTIO. Fast Transient Response Optimized with. Ceramic … |
| File Format / Size | PDF / 265 Kb |
| Document Language | English |
FEATURES. DESCRIPTIO. Fast Transient Response Optimized with. Ceramic Output Capacitors. FET RDS(ON) Defines Dropout Voltage
Model Line for this Datasheet
Text Version of Document
LT3150 Fast Transient Response, Low Input Voltage, Very Low Dropout Linear Regulator Controller
U FEATURES DESCRIPTIO
■
Fast Transient Response Optimized with
The LT®3150 drives a low cost external N-channel MOSFET
Ceramic Output Capacitors
as a source follower to produce a fast transient response, ■
FET RDS(ON) Defines Dropout Voltage
very low dropout voltage linear regulator. Selection of the ■ ±
1% Reference Tolerance Over Temperature
N-channel MOSFET RDS(ON) allows dropout voltages below ■ Multifunction LDO Shutdown Pin with Latchoff 300mV for low VIN to low VOUT applications. ■ Fixed Frequency 1.4MHz Boost Converter Generates The LT3150 includes a fixed frequency boost regulator MOSFET Gate Drive that generates gate drive for the N-channel MOSFET. The ■ Internally Compensated Boost Converter Uses Tiny internally compensated current mode PWM architecture Capacitors and Inductor combined with the 1.4MHz switching frequency permits ■ Independent Boost Converter Shutdown Control the use of tiny, low cost capacitors and inductors. Permits LDO Output Voltage Supply Sequencing ■ 16-Lead SSOP Package The LT3150’s transient load performance is optimized with ceramic output capacitors. A precision 1.21V refer-
U
ence accommodates low voltage supplies.
APPLICATIO S
Protection includes a high side current limit amplifier that ■ Microprocessor, ASIC and I/O Supplies activates a fault timer circuit. A multifunction shutdown ■ Very Low Dropout Input-to-Output Conversion pin provides either current limit time-out with latchoff, ■ Logic Termination Supplies overvoltage protection or thermal shutdown. Independent , LTC and LT are registered trademarks of Linear Technology Corporation. shutdown control of the boost converter provides on/off and sequencing control of the LDO output voltage.
U TYPICAL APPLICATIO 1.8V to 1.5V, 4A Very Low Dropout Linear Regulator Transient Response for (Typical Dropout Voltage = 65mV at IOUT = 4A) 0.1A to 4A Output Load Step
MBR0520L + L1 C1 6.19k LT3150 10µH 50mV/DIV 4.7µF 1% VIN2 SW FB1 VIN1 1.37k SHDN2 SHDN1 1% V SWGND I IN POS + C 1.8V GND I IN NEG 5.1Ω 220µF Si4410 2A/DIV GND GATE 2.5V VOUT FB2 ×2 1.5V COMP 243Ω 4A 1.5k 1% 2.2µF ×10 X5R CERAMIC 3150 TA02 6800pF 50pF 1020Ω 0805 CASE 20µs/DIV 1% CIN: PANASONIC SP SERIES EEFUE0E221R 20% C1: AVX TAJA475M020R 20V 20% 3150 TA01 L1: MURATA LQH32CN100K11 OR SUMIDA CDRH3D16100 3150f 1
U FEATURES DESCRIPTIO
■
Fast Transient Response Optimized with
The LT®3150 drives a low cost external N-channel MOSFET
Ceramic Output Capacitors
as a source follower to produce a fast transient response, ■
FET RDS(ON) Defines Dropout Voltage
very low dropout voltage linear regulator. Selection of the ■ ±
1% Reference Tolerance Over Temperature
N-channel MOSFET RDS(ON) allows dropout voltages below ■ Multifunction LDO Shutdown Pin with Latchoff 300mV for low VIN to low VOUT applications. ■ Fixed Frequency 1.4MHz Boost Converter Generates The LT3150 includes a fixed frequency boost regulator MOSFET Gate Drive that generates gate drive for the N-channel MOSFET. The ■ Internally Compensated Boost Converter Uses Tiny internally compensated current mode PWM architecture Capacitors and Inductor combined with the 1.4MHz switching frequency permits ■ Independent Boost Converter Shutdown Control the use of tiny, low cost capacitors and inductors. Permits LDO Output Voltage Supply Sequencing ■ 16-Lead SSOP Package The LT3150’s transient load performance is optimized with ceramic output capacitors. A precision 1.21V refer-
U
ence accommodates low voltage supplies.
APPLICATIO S
Protection includes a high side current limit amplifier that ■ Microprocessor, ASIC and I/O Supplies activates a fault timer circuit. A multifunction shutdown ■ Very Low Dropout Input-to-Output Conversion pin provides either current limit time-out with latchoff, ■ Logic Termination Supplies overvoltage protection or thermal shutdown. Independent , LTC and LT are registered trademarks of Linear Technology Corporation. shutdown control of the boost converter provides on/off and sequencing control of the LDO output voltage.
U TYPICAL APPLICATIO 1.8V to 1.5V, 4A Very Low Dropout Linear Regulator Transient Response for (Typical Dropout Voltage = 65mV at IOUT = 4A) 0.1A to 4A Output Load Step
MBR0520L + L1 C1 6.19k LT3150 10µH 50mV/DIV 4.7µF 1% VIN2 SW FB1 VIN1 1.37k SHDN2 SHDN1 1% V SWGND I IN POS + C 1.8V GND I IN NEG 5.1Ω 220µF Si4410 2A/DIV GND GATE 2.5V VOUT FB2 ×2 1.5V COMP 243Ω 4A 1.5k 1% 2.2µF ×10 X5R CERAMIC 3150 TA02 6800pF 50pF 1020Ω 0805 CASE 20µs/DIV 1% CIN: PANASONIC SP SERIES EEFUE0E221R 20% C1: AVX TAJA475M020R 20V 20% 3150 TA01 L1: MURATA LQH32CN100K11 OR SUMIDA CDRH3D16100 3150f 1
