My Inquiry
My Account
Analog Devices Inc. LT1170IT#PBF
- Part No.:
- LT1170IT#PBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- TO-220-5
- Datasheet:
-
LT1170IT#PBF.pdf
- Description:
- IC REG BUCK BOOST ADJ 5A TO220-5
- Quantity:
- Payment:
- Shipping:
Inventory:4,757
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT1170IT#PBF from Analog Devices (formerly Linear Technology) is a monolithic 5A, 100kHz current-mode switching regulator IC in a 5-lead plastic TO-220 package. It integrates a high-current power switch, oscillator, error amplifier, and protection circuitry, operates from 3V to 60V input, delivers up to 100W output power, and supports buck, boost, flyback, forward, inverting, and Cuk topologies - used in industrial DC-DC conversion where wide VIN and robust overload protection are required.
For engineers reviewing the LT1170IT#PBF datasheet, LT1170IT#PBF pinout, LT1170IT#PBF application, or LT1170IT#PBF equivalent, key selection criteria include its −40°C to 100°C operating temperature range, internal 5A/75V switch, 6mA quiescent current, adaptive anti-saturation drive, and externally programmable shutdown with 50µA standby current - all critical for ruggedized power supply design.
Technical Context
The LT1170IT#PBF implements current-mode control: the internal oscillator initiates each switching cycle, and the integrated 5A power switch turns off when sensed current reaches a level set by the VC pin voltage. This architecture provides inherent cycle-by-cycle current limiting and excellent line/load transient response without external compensation complexity.
It features dual error amplifiers - one for standard regulation (1.224V reference at FB pin), another for isolated flyback mode (15.0V flyback reference) - selectable via FB pin voltage threshold (0.45V). The VC pin serves four functions: frequency compensation node, current limit programming input, soft-start control point, and shutdown activation (≤0.15V).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switch Current Limit | 5A typical at TJ ≥ 25°C; enables direct 5A load delivery without external MOSFETs in buck/boost designs. |
| Input Voltage Range | 3V to 60V; supports wide-range industrial inputs including 24V, 48V, and battery systems down to 3V. |
| Quiescent Current | 6mA typical; minimizes no-load power loss in always-on systems like remote sensors or backup supplies. |
| Shutdown Current | 50µA typical; allows ultra-low-power standby in battery-powered applications requiring extended shelf life. |
| Switch Breakdown Voltage | 65V (standard grade); ensures safe operation with 48V nominal inputs plus transients up to 60V. |
| Switch On-Resistance | 0.15Ω typical; limits conduction loss to ≤0.375W at 5A, reducing thermal stress in TO-220 package. |
| Switching Frequency | 100kHz typical; balances EMI control, inductor size, and efficiency for mid-power converters. |
| Reference Voltage | 1.224V at FB pin; sets output voltage precision in non-isolated topologies using standard resistor dividers. |
Pinout & Package
LT1170IT#PBF uses a 5-lead plastic TO-220 package (T package) with tab connected to GND. Pin 1 = VIN, Pin 2 = VSW, Pin 3 = GND, Pin 4 = FB, Pin 5 = VC. All pins are electrically defined; no NC or reserved pins.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN (Pin 1) | Main power input | Accepts 3V–60V unregulated DC; powers internal LDO and switch driver; requires local 1µF ceramic bypass. |
| VSW (Pin 2) | Switch drain output | Connects directly to external inductor/diode in buck/boost; carries full switched current; must be routed with low-inductance layout. |
| GND (Pin 3) | Power and signal ground | Common return for internal circuits, switch source, and feedback network; tab is electrically tied to this pin. |
| FB (Pin 4) | Feedback input | Senses output voltage divider; <0.45V selects flyback mode (15V ref); 1.224V target enables standard regulation. |
| VC (Pin 5) | Error amplifier output / control | Programs current limit (0–2V range), enables soft-start (capacitor), and triggers shutdown (<0.15V). |
Key Features
| Feature | Design Value |
|---|---|
| Integrated 5A/75V power switch | Eliminates external MOSFET and gate driver, reducing BOM count and layout area in 50–100W converters. |
| Adaptive anti-saturation drive | Maintains high efficiency across 0.1A–5A load range by dynamically adjusting base/gate drive to prevent transistor saturation. |
| Flyback-regulated mode | Enables fully floating, transformer-isolated outputs up to breakdown voltage of windings - ideal for medical or safety-isolated supplies. |
| Externally synchronized operation | Supports 120–160kHz synchronization to avoid beat frequencies in multi-rail systems or meet EMI band requirements. |
| Self-protected against overloads | Includes cycle-by-cycle current limiting, thermal foldback (untested but functional), and shutdown - no external current sense needed. |
| Standard 5-pin TO-220 footprint | Enables drop-in replacement of linear regulators or legacy switchers; compatible with existing heatsink mounting and assembly processes. |
Applications
| Industrial DC-DC Conversion | Battery-Powered Upconversion |
|---|---|
Use Scenario: Converting 24V rail to 12V/5A for PLC I/O modules in factory automation cabinets with ambient temperatures up to 70°C. IC Role / Device Role / Timing Role: Primary switching controller implementing synchronous buck topology with fixed 100kHz frequency and current-mode regulation. Use Value: Delivers 60W continuous output with 6mA quiescent draw, enabling fanless enclosure design and meeting EN 61000-6-3 Class A emissions. | Use Scenario: Boosting 3.6V Li-ion battery to 12V for portable test equipment requiring >2A peak load and >100h standby life. IC Role / Device Role / Timing Role: High-efficiency boost converter with programmable shutdown (VC pin) and flyback-capable feedback for auxiliary rails. Use Value: 50µA shutdown current extends battery shelf life; 5A switch handles pulsed loads without external FETs; TO-220 tab aids thermal management in compact enclosures. |
| Isolated Flyback Power Supply | High-Voltage Inverter Stage |
Use Scenario: Generating ±15V dual outputs from 48V telecom input in telecom line card with reinforced isolation per IEC 60950-1. IC Role / Device Role / Timing Role: Flyback controller using FB pin threshold to activate 15V flyback reference; regulates primary-side reflected voltage. Use Value: Eliminates optocoupler and secondary-side TL431; achieves <±3% output regulation across line/load; supports fully floating secondaries. | Use Scenario: Inverting +24V to –24V for op-amp bias in industrial data acquisition front-ends requiring low noise and rail-to-rail swing. IC Role / Device Role / Timing Role: Inverting topology controller with internal 5A switch handling bidirectional current flow during polarity reversal. Use Value: Single-chip solution replaces discrete charge-pump or transformer-based inverters; 0.15Ω RDS(on) limits dropout to <1.2V at 2A, preserving headroom. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar switching regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3703IGN#TRPBF | External MOSFET driver; 4V–36V input; no integrated switch; 100kHz sync capable. | Requires external high-side/lower FETs; suited for >10A or >100W designs where thermal partitioning is critical. | Select LTC3703 when higher power, better thermal management, or custom switch selection (SiC/GaN) is required - not a pin-compatible replacement. |
| LM5088MHX/NOPB | 5A integrated switch; 4.5V–75V input; 1MHz switching; no flyback mode; different pinout (8-pin SOIC). | Lacks flyback regulation capability; optimized for high-frequency, small-inductor designs; no VC pin multifunctionality. | Choose LM5088 for space-constrained 12V–48V systems needing 1MHz operation and lower EMI filtering cost - requires PCB redesign. |
Compared with LTC3703IGN#TRPBF and LM5088MHX/NOPB, the LT1170IT#PBF uniquely combines 5A integration, flyback mode, −40°C to 100°C rating, and TO-220 mechanical compatibility - making it optimal for ruggedized, medium-power, multi-topology industrial supplies where simplicity and reliability outweigh ultra-high frequency or extreme power scaling.
Availability
LT1170IT#PBF is available at Aetrix Electronics and suitable for industrial DC-DC conversion, battery-powered upconversion, and isolated flyback power supply applications requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.
Supply support for LT1170IT#PBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Analog Devices acquired Linear Technology in 2017 and maintains full product support, datasheets, and application notes for legacy Linear parts including the LT1170 series.
The LT1170 family was designed as a monolithic, "bust-proof" switching regulator platform for industrial and embedded systems demanding wide input range, high output power, and topology flexibility without external switch complexity.
FAQ
What is the maximum continuous output power achievable with the LT1170IT#PBF?
The LT1170IT#PBF delivers up to 100W of continuous output power in buck or boost configurations when properly heatsinked, based on its 5A switch current limit and 60V input capability. Actual power depends on topology, ambient temperature, and PCB thermal design - for example, 60W is reliably achievable at 70°C ambient with minimal copper in a TO-220 package. Derating applies above 100°C junction temperature.
Does the LT1170IT#PBF support flyback topology, and how is it configured?
Yes, the LT1170IT#PBF supports flyback topology via its dedicated flyback-regulated mode. Configuration requires pulling the FB pin below 0.45V (typically with a resistor divider from output), which activates the 15.0V flyback reference and connects the flyback error amplifier. This enables fully floating, transformer-isolated outputs without optocouplers or secondary-side regulation components.
What is the function of the VC pin on the LT1170IT#PBF, and how is it used for shutdown?
The VC pin on the LT1170IT#PBF serves four functions: error amplifier output, current limit programming node, soft-start capacitor connection, and shutdown control. For shutdown, pulling VC to ≤0.15V (e.g., via open-collector transistor) reduces total supply current to 50µA - enabling ultra-low-power standby. The pin voltage between 0.9V and 2.0V sets switch current limit proportionally.
Can the LT1170IT#PBF be synchronized to an external clock, and what is the supported frequency range?
Yes, the LT1170IT#PBF supports external synchronization by pulling the VC pin to ground with narrow pulses (≤0.3µs width). It locks to external clocks in the 120kHz to 160kHz range, allowing EMI reduction through frequency dithering or alignment with system clocks - useful in multi-rail power systems where switching noise interference must be avoided.
What thermal considerations apply to the LT1170IT#PBF in its TO-220 package?
The LT1170IT#PBF in TO-220 has θJA = 75°C/W. At full 5A load and 60V input, junction temperature rise can exceed safe limits without heatsinking. Designers must calculate total dissipation (switch + quiescent) and ensure TJ ≤ 100°C. Use of thermal vias, 2oz copper, and optional heatsink is recommended for >30W continuous operation - especially in sealed enclosures or high ambient environments.
LT1170IT#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- TO-220-5
- Packaging:
- Tube
- Product Status:
- Active
- Function:
- Step-Up, Step-Down, Step-Up/Step-Down
- Output Configuration:
- Positive or Negative
- Topology:
- Buck, Boost, Cuk, Flyback, Forward Converter
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 3V
- Voltage - Input (Max):
- 40V
- Voltage - Output (Min/Fixed):
- 1.244V
- Voltage - Output (Max):
- 65V (Switch)
- Current - Output:
- 5A (Switch)
- Frequency - Switching:
- 100kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 100°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220-5
LT1170IT#PBF FAQ
1.How can I place an order for LT1170IT#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT1170IT#PBF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LT1170IT#PBF reliable?
The price and inventory of LT1170IT#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT1170IT#PBF is usually 5 days.
3.What payment methods are accepted for LT1170IT#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT1170IT#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT1170IT#PBF?
LT1170IT#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT1170IT#PBF order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LT1170IT#PBF?
For technical support, including LT1170IT#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT1170IT#PBF requirements.
6.How does Aetrix verify that LT1170IT#PBF is sourced from the original manufacturer or authorized distributors?
All LT1170IT#PBF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LT1170IT#PBF meets industry standards.
7.What is the process for return or replacement of LT1170IT#PBF?
All LT1170IT#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LT1170IT#PBF, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LT1170IT#PBF part is unused and in its original packaging.
Return procedure for LT1170IT#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT1170IT#PBF Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
