Datasheet LT3150 (Analog Devices)
| Hersteller | Analog Devices |
| Beschreibung | Fast Transient Response, Low Input Voltage, Very Low Dropout Linear Regulator Controller |
| Seiten / Seite | 20 / 1 — FEATURES. DESCRIPTIO. Fast Transient Response Optimized with. Ceramic … |
| Dateiformat / Größe | PDF / 265 Kb |
| Dokumentensprache | Englisch |
FEATURES. DESCRIPTIO. Fast Transient Response Optimized with. Ceramic Output Capacitors. FET RDS(ON) Defines Dropout Voltage
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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