My Inquiry
My Account
Analog Devices Inc. LT3579EFE-1#PBF
- Part No.:
- LT3579EFE-1#PBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- 20-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Datasheet:
-
LT3579EFE-1#PBF.pdf
- Description:
- IC REG BST CHRG PUMP ADJ 20TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:232
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT3579EFE-1#PBF from Analog Devices is a 6A dual-phase PWM DC/DC converter with integrated 42V master and 2.6A slave NPN switches, fault protection (output short, overvoltage, overtemperature), and configurable undervoltage lockout. It supports boost, inverting, SEPIC, and flyback topologies - delivering 12V at 1.7A or –12V at 1.2A from 5V input - and targets local power supplies in automotive ECUs and display bias circuits.
For engineers reviewing the LT3579EFE-1#PBF datasheet, LT3579EFE-1#PBF pinout, LT3579EFE-1#PBF application, or LT3579EFE-1#PBF equivalent, key selection criteria include its dual-phase capability (LT3579-1 variant), 200kHz–2.5MHz programmable switching frequency, master/slave current sharing ratio (0.78 A/A), and GATE-driven external PMOS for output disconnect during faults.
Technical Context
The LT3579EFE-1#PBF implements constant-frequency current-mode control with frequency foldback (1/6× normal fOSC) during startup or fault recovery. Its dual-phase architecture enables interleaved operation when synchronized with another LT3579-1, reducing input/output ripple and thermal stress.
It integrates a precision 1.215V positive feedback reference and 9mV negative reference, error amplifier with 70V/V gain and 250µmhos transconductance, and dedicated FAULT pin logic that pulls low on SW1 overcurrent (>3.4A), VIN overvoltage (>16.2V), SW overvoltage (>42V), or die temperature >165°C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switch Configuration | Dual-phase capable master/slave NPN: 3.4A/2.6A (min), combined 6A peak current limit |
| Input Voltage Range | 2.5V to 16V operating; 40V transient survival - supports wide automotive and industrial rails |
| Switching Frequency | 200kHz to 2.5MHz via RT resistor or external SYNC - enables EMI optimization and compact magnetics |
| Feedback Reference | 1.215V (boost/SEPIC) or 9mV (inverting) - sets precise output regulation point with minimal external components |
| VCE(SAT) | 250mV typical at 5.5A (SW1+SW2 tied) - reduces conduction loss and thermal load in high-current designs |
| Soft-Start Control | SS pin charges to ~2.1V via internal 250kΩ; controls ramp rate of switch current and GATE pull-down (0–933µA) |
| CLKOUT Function | Buffered oscillator output with fixed 50% duty cycle (LT3579-1); usable for multiphase sync or junction temperature monitoring |
Pinout & Package
LT3579EFE-1#PBF is housed in a 20-lead plastic TSSOP package (FE) with exposed pad (Pin 21) soldered to PCB ground for thermal management (θJA = 38°C/W).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| GATE (Pin 1 & 3) | PMOS gate drive output | Pull-down current source (0–933µA) controlled by SS voltage; enables external PMOS for output disconnect during fault |
| FAULT (Pin 2 & 4) | Bidirectional fault indicator | Active-low open-drain; pulled low internally on overcurrent/overvoltage/overtemperature, or externally to force shutdown |
| VIN (Pin 3 & 5) | Main input supply | 2.5V–16V operating range; withstands 40V transients; requires local ceramic bypass |
| SW1 (Pins 4–7) | Master NPN collector | Handles ≥3.4A peak current; connects to inductor/transformer primary; minimize trace area for EMI reduction |
| GND (Pins 8, 9, 21) | Power and signal ground | Exposed pad (Pin 21) must be soldered to PCB ground plane for thermal and electrical integrity |
| SW2 (Pins 10–13) | Slave NPN collector | Handles ≥2.6A peak current; used in dual-phase or charge-pump configurations; shares layout constraints with SW1 |
| CLKOUT (Pin 14) | Synchronized clock output | 50% duty cycle (LT3579-1); matches internal oscillator or SYNC input frequency; supports multiphase regulator coordination |
| SHDN (Pin 15) | Enable/disable control | High-threshold (1.33V typ.) with 30mV hysteresis; supports configurable UVLO using external resistor divider |
| RT (Pin 16) | Oscillator timing | Resistor-to-ground sets free-running frequency (200kHz–2.5MHz); no floating allowed |
| SYNC (Pin 17) | External clock input | Accepts 0.4V–1.3V logic levels; overrides RT setting; <3/4 fSYNC/fOSC recommended for reliable locking |
| SS (Pin 18) | Soft-start capacitor node | Charges to 1.8V then 2.1V; controls ramp rate of switch current and GATE pull-down; initiates timeout sequence on fault |
| VC (Pin 19) | Error amplifier output | Connects to external compensation network (RC, CC); sets loop stability and transient response |
| FB (Pin 20) | Feedback input | Accepts positive (1.215V ref) or negative (9mV ref) feedback; determines output voltage setpoint and regulation mode |
Key Features
| Feature | Design Value |
|---|---|
| Dual-phase synchronization | CLKOUT phase-shifted 180° (LT3579-1) enables interleaved operation with second LT3579-1, cutting input ripple by ~50% |
| Output short-circuit protection | Sample Mode forces Q1/Q2 on every cycle to detect inductor current >3.4A; triggers FAULT within microseconds |
| Configurable UVLO | SHDN pin accepts external resistor divider to set precise VIN turn-on threshold (e.g., 9V for automotive cold-crank immunity) |
| Integrated fault recovery | SS pin drives automatic charge/discharge timeout (100ms–1s depending on CSS) before retry - prevents latch-up during sustained faults |
| Thermal-aware clock output | CLKOUT duty cycle varies linearly with junction temperature - eliminates need for external thermal sensor in space-constrained designs |
Applications
| Automotive Engine Control Unit (ECU) Power | Vacuum Fluorescent Display (VFD) Bias Supply |
|---|---|
Use Scenario: Generating stable 12V/–12V rails from noisy 12V battery in engine bay under cold-crank (4.5V) and load-dump (40V) conditions. IC Role / Device Role / Timing Role: Dual-switch DC/DC controller managing boost and inverting outputs; FAULT pin interfaces with ECU watchdog to halt injection if rail fails. Use Value: 40V transient tolerance and 6A current headroom ensure uninterrupted operation during cranking; GATE-driven PMOS isolates downstream circuitry during overvoltage events. | Use Scenario: Providing isolated ±30V bias for VFD anode/grid segments in industrial panel meters with tight EMI limits. IC Role / Device Role / Timing Role: Inverting converter generating negative rail; CLKOUT synchronizes with adjacent boost stage to suppress beat frequencies. Use Value: 2.5MHz max switching frequency allows use of small 1µH inductors; dual-phase capability (LT3579-1) reduces output capacitor count by 30% vs single-phase. |
| TFT-LCD Panel Bias Supply | Industrial Local Power Supply |
Use Scenario: Generating AVDD (+15V), VGH (+25V), and VGL (–10V) from 5V system rail in portable medical displays. IC Role / Device Role / Timing Role: Configured as SEPIC for AVDD, inverting for VGL; RT pin sets 1.2MHz to avoid AM radio band. Use Value: Single IC replaces three discrete regulators; soft-start prevents inrush into large panel capacitance; FAULT pin halts all rails simultaneously on short. | Use Scenario: Point-of-load conversion in programmable logic controller (PLC) backplane where space, reliability, and fault containment are critical. IC Role / Device Role / Timing Role: Boost converter powering 24V I/O modules; SHDN pin tied to PLC watchdog timer for automatic reset after brownout. Use Value: 125°C junction rating and overtemperature shutdown protect against enclosure overheating; exposed-pad TSSOP ensures 38°C/W thermal resistance without heatsink. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-switch DC/DC controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3891EFE#PBF | Single-channel synchronous buck controller; no integrated switches; supports up to 60V VIN; requires external MOSFETs | Used in higher-efficiency, higher-power (>10A) buck applications; lacks integrated fault protection and dual-phase sync | Select when efficiency >95% and thermal budget allow discrete FETs; not drop-in for LT3579EFE-1#PBF's integrated switch topology |
| LT8330EFE#PBF | Single-switch 6A boost controller; no slave switch or dual-phase capability; 40V switch rating; simpler FB architecture (1.22V ref only) | Suitable for non-inverting boost-only designs; lacks output short detection and sample-mode protection | Choose for cost-sensitive, single-rail boost where dual-phase and fault robustness are unnecessary |
Compared with LTC3891EFE#PBF and LT8330EFE#PBF, the LT3579EFE-1#PBF uniquely combines integrated dual NPN switches, 180° phase-shifted CLKOUT, and hardware-enforced fault isolation - making it optimal for compact, fault-tolerant, multi-rail local supplies where board space and safety margins are constrained.
Availability
LT3579EFE-1#PBF is available at Aetrix Electronics and suitable for automotive ECU power, VFD bias supplies, TFT-LCD panel bias, and industrial local power supply designs requiring stable component supply across extended temperature ranges (–40°C to 125°C).
Supply support for LT3579EFE-1#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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.
The LT3579 product line delivers highly integrated, fault-protected DC/DC controllers for demanding local power applications - designed specifically to simplify robust, compact, and thermally efficient power conversion in harsh environments.
FAQ
What is the key functional difference between LT3579EFE-1#PBF and the standard LT3579EFE#PBF?
The LT3579EFE-1#PBF is the dual-phase variant: its CLKOUT signal is 180° out of phase with the internal oscillator and maintains a fixed 50% duty cycle, enabling true interleaved operation with a second LT3579-1 device. The standard LT3579EFE#PBF has a variable CLKOUT duty cycle (~42%) and is not optimized for phase synchronization. This distinction makes LT3579EFE-1#PBF essential for reducing ripple and thermal stress in high-current, multi-phase designs.
How does the FAULT pin behavior differ during internal versus external fault triggering in LT3579EFE-1#PBF?
When an internal fault occurs (e.g., SW1 overcurrent or overtemperature), the LT3579EFE-1#PBF actively pulls the FAULT pin low, disables CLKOUT and power switches, and initiates the SS timeout sequence. When the FAULT pin is pulled low externally (e.g., by a microcontroller), the LT3579EFE-1#PBF responds identically - turning off switches and entering fault state - but does not assert internal FAULT until the external condition clears. Both paths result in identical protection actions, ensuring deterministic system-level fault containment.
Can LT3579EFE-1#PBF be used in a flyback configuration, and what design considerations apply?
Yes, LT3579EFE-1#PBF supports flyback topology using SW1 as the primary switch and optional external synchronous rectifier control. Key considerations include configuring FB for the chosen output polarity (positive or negative reference), selecting transformer turns ratio to meet VSW <42V constraint, and ensuring minimum off-time (45ns) accommodates leakage inductance ringing. The integrated fault protection remains fully active, detecting primary overcurrent and output overvoltage via optocoupler feedback to FB.
What is the role of the GATE pin in LT3579EFE-1#PBF, and how is its current profile controlled?
The GATE pin in LT3579EFE-1#PBF is a programmable pull-down current source (0–933µA) that drives the gate of an external PMOS transistor for output disconnect. Its current scales linearly with SS pin voltage: below 500mV, current is proportional; above 500mV, it saturates at 933µA. This enables soft turn-on of the PMOS during startup (limiting inrush) and hard turn-off during faults - directly linking power path control to the IC's internal fault and soft-start states.
Does LT3579EFE-1#PBF require external compensation, and where is it connected?
Yes, LT3579EFE-1#PBF requires external Type II or Type III compensation connected to the VC pin (Pin 19). The compensation network - typically an RC series branch plus optional capacitor to ground - stabilizes the current-mode control loop by setting dominant pole, zero, and high-frequency roll-off. Proper compensation is critical for maintaining phase margin >45° and preventing oscillation, especially when driving high-capacitance loads like LCD bias rails or ECU microcontroller supplies.
LT3579EFE-1#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 20-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Function:
- Step-Up, Step-Up/Step-Down
- Output Configuration:
- Positive or Negative
- Topology:
- Boost, Charge Pump, Cuk, Flyback, SEPIC
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2.5V
- Voltage - Input (Max):
- 16V
- Voltage - Output (Min/Fixed):
- 1.215V
- Voltage - Output (Max):
- 42V (Switch)
- Current - Output:
- 6A (Switch)
- Frequency - Switching:
- 200kHz ~ 2.5MHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-TSSOP-EP
LT3579EFE-1#PBF FAQ
1.How can I place an order for LT3579EFE-1#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT3579EFE-1#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 LT3579EFE-1#PBF reliable?
The price and inventory of LT3579EFE-1#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT3579EFE-1#PBF is usually 5 days.
3.What payment methods are accepted for LT3579EFE-1#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT3579EFE-1#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT3579EFE-1#PBF?
LT3579EFE-1#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT3579EFE-1#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 LT3579EFE-1#PBF?
For technical support, including LT3579EFE-1#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT3579EFE-1#PBF requirements.
6.How does Aetrix verify that LT3579EFE-1#PBF is sourced from the original manufacturer or authorized distributors?
All LT3579EFE-1#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 LT3579EFE-1#PBF meets industry standards.
7.What is the process for return or replacement of LT3579EFE-1#PBF?
All LT3579EFE-1#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LT3579EFE-1#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 LT3579EFE-1#PBF part is unused and in its original packaging.
Return procedure for LT3579EFE-1#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT3579EFE-1#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…
