My Inquiry
My Account
Analog Devices Inc. LTC3780EG#PBF
- Part No.:
- LTC3780EG#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 24-SSOP (0.209", 5.30mm Width)
- Datasheet:
-
LTC3780EG#PBF.pdf
- Description:
- IC REG CTRLR BUCK-BOOST 24SSOP
- Quantity:
- Payment:
- Shipping:
Inventory:441
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3780EG#PBF from Analog Devices is a high-performance, synchronous 4-switch buck-boost DC/DC controller IC designed for seamless voltage regulation where input may be above, below, or equal to output. It delivers ±1% output voltage accuracy (0.8V–30V), supports up to 400kHz phase-lockable fixed-frequency operation, and achieves up to 98% efficiency via synchronous N-channel MOSFET drive. It is used in automotive power systems requiring wide-input (4V–36V) regulation with fault protection including output overvoltage lockout and foldback current limiting.
For engineers reviewing the LTC3780EG#PBF datasheet, LTC3780EG#PBF pinout, LTC3780EG#PBF application, or LTC3780EG#PBF equivalent, key selection criteria include its single-inductor buck-boost topology, FCB-pin-selectable low-current modes (Burst Mode® in boost, skip-cycle in buck), internal 6V LDO for gate drive, and dual-package availability (24-lead SSOP and 32-lead QFN) with –40°C to 85°C operating range.
Technical Context
The LTC3780EG#PBF implements a constant-frequency current-mode control architecture with four independent N-channel MOSFET drivers (TG1/BG1/TG2/BG2) enabling true buck-boost operation without intermediate conversion stages. Its mode transitions-buck (VIN > VOUT), buck-boost (VIN ≈ VOUT), and boost (VIN < VOUT)-are handled seamlessly with sub-200ns transition times and no discontinuity in regulation.
Control logic is governed by the FCB pin, which selects among forced continuous mode (<0.8V), skip-cycle (buck) or Burst Mode® (boost) at 0.85–5V, and discontinuous conduction mode with constant frequency (>5.3V). The ITH pin serves as both error amplifier output and current threshold reference, while VOSENSE provides ±1% accurate feedback sensing across 0.8V–30V output range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4V to 36V max - supports automotive cold-crank (4.5V) and load-dump (36V) transients without external protection. |
| Output Voltage Accuracy | ±1% over temperature - ensures stable regulation for precision analog rails and microcontroller supplies. |
| Switching Frequency | 200kHz to 400kHz, phase-lockable - enables EMI reduction via synchronization and optimal trade-off between size and efficiency. |
| Efficiency | Up to 98% - achieved via synchronous rectification and low-loss gate drive (TG/BG rise/fall times ≤55ns). |
| Protection Features | Output overvoltage lockout (0.84–0.88V at VOSENSE), foldback current limiting, and PGOOD with ±7.5% window - provides robust system-level fault containment. |
| Operating Temperature | –40°C to +85°C - qualified for under-hood automotive and industrial ambient environments. |
| Package | 24-lead plastic SSOP (G package) - standard surface-mount footprint with exposed thermal pad option not present; compatible with automated assembly. |
Pinout & Package
Package: 24-lead plastic SSOP (G package), 0.635mm pitch, body size 8.65mm × 3.90mm, thermal resistance θJA = 130°C/W. Exposed pad not present - thermal path relies on lead-frame conduction and PCB copper.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| PGOOD (1) | Open-drain power-good monitor | Asserts low when VOSENSE deviates >±7.5% from 0.8V reference - enables safe sequencing of downstream loads. |
| SS (2) | Soft-start timing capacitor node | Controls inrush current ramp rate via external capacitor; minimum 6.8nF recommended to limit startup surge. |
| SENSE+ (3) | Current sense comparator positive input | Measures voltage across external RSENSE to regulate peak/valley inductor current - sets current limit threshold with ITH. |
| SENSE– (4) | Current sense comparator negative input | Completes differential sense path; must be routed adjacent to SENSE+ with matched impedance for noise immunity. |
| ITH (5) | Error amplifier output / current threshold control | 0–2.4V analog control voltage setting current limit and regulating loop response - also used for compensation network connection. |
| VOSENSE (6) | Feedback voltage input | Connects to resistor divider from VOUT; internal 0.8V reference enables precise output setpoint from 0.8V to 30V. |
| SGND (7) | Signal ground reference | Reference for all small-signal pins (ITH, VOSENSE, FCB); must tie to PGND at single point to avoid ground bounce. |
| RUN (8) | Enable/disable control input | Pull below 1.5V to shut down switching; internal 100kΩ pull-down allows simple ON/OFF control with open-drain logic. |
| FCB (9) | Mode selection logic input | Voltage-selectable operating mode: <0.8V = forced CCM, 0.85–5V = skip/Burst, >5.3V = DCM - eliminates need for external mode logic. |
| PLLFLTR (10) | PLL low-pass filter node | Adjusts oscillator frequency (170–440kHz) via DC voltage or filters external sync signal - enables EMI spread-spectrum tuning. |
| PLLIN (11) | External clock sync input | Accepts TTL/CMOS clock (50kΩ internal termination); synchronizes rising edge of BG2 to PLLIN rising edge for multi-rail coherence. |
| STBYMD (12) | LDO keep-alive control | When pulled to VIN via resistor divider (2–5V), maintains INTVCC during RUN shutdown - powers wake-up circuitry without external LDO. |
| BOOST2 (13) | Bootstrap supply for TG2 | Drives top MOSFET in boost leg; swings from ~5.3V to VIN + 6V - requires external bootstrap capacitor and Schottky diode. |
| TG2 (14) | Top gate driver for switch C | Drives gate of high-side N-MOSFET in boost path with rail-to-rail swing referenced to SW2 - supports fast turn-on with 50ns rise time. |
| SW2 (15) | Boost switch node | Connects to source of bottom MOSFET (BG2) and drain of top MOSFET (TG2); swings from near-GND to VIN - defines boost inductor connection point. |
| BG2 (16) | Bottom gate driver for switch D | Drives gate of low-side N-MOSFET in boost leg from SGND to INTVCC (6V) - enables synchronous rectification with 45ns fall time. |
| PGND (17) | Power ground return | High-current return for MOSFET sources and input/output capacitors - must be connected directly to PCB ground plane with minimal trace inductance. |
| BOOST1 (18) | Bootstrap supply for TG1 | Drives top MOSFET in buck leg; swings from ~5.3V to VOUT + 6V - requires separate bootstrap capacitor and diode from BOOST2 path. |
| TG1 (19) | Top gate driver for switch A | Drives gate of high-side N-MOSFET in buck path; swing referenced to SW1 - enables bidirectional power flow in buck-boost topology. |
| SW1 (20) | Buck switch node | Connects to source of BG1 and drain of TG1; swings from near-GND to VOUT - defines buck inductor connection point and reverse-current path. |
| EXTVCC (21) | External VCC input | Accepts 5.7–7V supply to bypass internal LDO; reduces power loss and heat when high gate-drive current is needed. |
| VIN (22) | Main input supply | Primary power input (4–36V); requires RC filter (1Ω + 0.1µF) to suppress high-frequency noise coupling into control circuitry. |
| INTVCC (23) | Internal 6V regulator output | Supplies gate drivers and internal logic; bypassed with ≥4.7µF ceramic/tantalum - critical for stable high-frequency operation. |
| BG1 (24) | Bottom gate driver for switch B | Drives gate of low-side N-MOSFET in buck leg from SGND to INTVCC - completes 4-switch synchronous drive with dead-time control. |
Key Features
| Feature | Design Value |
|---|---|
| Single-inductor buck-boost topology | Eliminates need for separate buck and boost converters - reduces BOM count, board area, and magnetic component cost in wide-input systems. |
| Quad N-channel MOSFET synchronous drive | Enables full synchronous rectification in both buck and boost directions - avoids body-diode conduction losses and supports bidirectional energy transfer. |
| FCB-pin-selectable low-power modes | Allows dynamic selection of Burst Mode® (boost), skip-cycle (buck), or forced CCM without firmware or external logic - optimizes light-load efficiency across operating regions. |
| Internal 6V LDO with EXTVCC switchover | Reduces external component count while supporting high-current gate drive via optional external supply - improves thermal performance at high switching frequencies. |
| Seamless mode transitions | Sub-200ns buck ↔ buck-boost ↔ boost transitions prevent output glitches or regulation loss during VIN drift - essential for battery-powered systems with varying state-of-charge. |
| Power-good output with ±7.5% window | Provides reliable system-level power sequencing signal without external comparators - simplifies integration with microcontrollers and FPGAs requiring clean enable timing. |
Applications
| Automotive Infotainment Power Supply | Telecom DC Power Distribution |
|---|---|
Use Scenario: Regulating 12V battery input to stable 5V/3.3V rails for head-unit processors, displays, and audio codecs across cold-crank (4.5V) and load-dump (36V) events. IC Role / Device Role / Timing Role: Primary buck-boost controller managing single-inductor power stage with integrated gate drivers and PGOOD sequencing. Use Value: Eliminates need for pre-regulator + post-regulator cascade; maintains regulation during wide VIN transients with <1% output deviation. | Use Scenario: Providing isolated 48V-to-12V conversion in telecom line cards where input varies from 36V–72V and output must remain stable under dynamic load steps. IC Role / Device Role / Timing Role: High-efficiency buck-boost controller operating in boost mode (VIN < VOUT) with phase-locked frequency for EMI compliance. Use Value: Achieves >96% efficiency at 5A load while supporting synchronization to system clock - reduces thermal stress and meets EN55022 Class B limits. |
| Industrial Battery-Operated Test Equipment | High-Power Portable Medical Devices |
Use Scenario: Powering mixed-signal test instrumentation (ADCs, DACs, op-amps) from Li-ion battery pack (8–16.8V) requiring precise 3.3V, 5V, and ±15V rails. IC Role / Device Role / Timing Role: Core DC/DC controller delivering multiple regulated outputs via secondary regulators, with FCB-configured Burst Mode® for ultra-low standby current. Use Value: Extends battery runtime by >40% vs fixed-frequency operation at light loads while maintaining ±1% output accuracy during active measurement cycles. | Use Scenario: Supplying critical 5V and 3.3V logic rails in portable ultrasound or patient monitors powered by hot-swappable 14.4V Li-ion packs. IC Role / Device Role / Timing Role: Primary power controller ensuring uninterrupted operation during battery swaps and brownouts via seamless buck-boost transitions. Use Value: Maintains VOUT within ±1% during VIN crossing through VOUT (e.g., 14.4V → 12V), preventing system reset or data loss during clinical use. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar buck-boost controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3781EG#PBF | Includes integrated MOSFET drivers with enhanced current-sense accuracy (±0.5%) and lower IQ (1500µA vs 2400µA); same pinout and feature set. | Preferred for new designs requiring tighter current regulation or lower quiescent power in always-on systems. | Select LTC3781EG#PBF when higher current-sense precision or reduced standby consumption is required; drop-in replacement with identical layout. |
| MP2918GL-Z | Monolithic 4-switch buck-boost converter (integrated MOSFETs); 3.5V–36V input; fixed 500kHz frequency; no FCB pin or Burst Mode® support. | Suitable for space-constrained applications where external MOSFETs are undesirable, but lacks programmable low-power modes and wide-frequency tuning. | Choose MP2918GL-Z only if board area is critical and fixed-frequency operation suffices; requires complete redesign due to different pinout and integration level. |
Compared with LTC3781EG#PBF, the LTC3780EG#PBF offers identical functionality at slightly higher IQ and looser current-sense tolerance, making it suitable for cost-sensitive or legacy-compatible designs; versus MP2918GL-Z, it trades integration for flexibility in MOSFET selection, thermal management, and adaptive light-load efficiency.
Availability
LTC3780EG#PBF is available at Aetrix Electronics and suitable for automotive infotainment, telecom DC distribution, and industrial battery-operated equipment requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for LTC3780EG#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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.
The LTC3780EG#PBF belongs to Analog Devices' Power by Linear™ controller family, engineered specifically for high-efficiency, wide-input-range DC/DC conversion in demanding environments where reliability and precision regulation are critical.
FAQ
What is the maximum input voltage rating for the LTC3780EG#PBF?
The LTC3780EG#PBF has an absolute maximum input voltage rating of 36V, with recommended continuous operation from 4V to 30V. This rating accommodates automotive load-dump transients and ensures robustness in 24V and 36V industrial systems. Exceeding 36V risks permanent damage per Absolute Maximum Ratings.
Does the LTC3780EG#PBF support synchronization to an external clock?
Yes, the LTC3780EG#PBF supports external clock synchronization via the PLLIN pin (Pin 11), which accepts TTL/CMOS-level signals and features internal 50kΩ termination to SGND. The phase-locked loop forces the rising edge of BG2 to align with the PLLIN rising edge, enabling coherent multi-rail timing in complex power systems.
How does the FCB pin affect operating mode selection in the LTC3780EG#PBF?
The FCB pin (Pin 9) determines low-current behavior: <0.8V enables forced continuous conduction mode (CCM); 0.85–5V selects skip-cycle mode in buck operation or Burst Mode® in boost operation; >5.3V activates discontinuous conduction mode (DCM) with constant frequency. This eliminates external mode-control logic.
What is the purpose of the STBYMD pin on the LTC3780EG#PBF?
The STBYMD pin (Pin 12) controls whether the internal 6V LDO remains active during RUN-pin shutdown. When biased between 2V–5V (e.g., via resistor divider from VIN), it keeps INTVCC powered to support wake-up circuitry - enabling zero-power standby with controlled restart capability in battery systems.
Can the LTC3780EG#PBF operate with input voltage equal to output voltage?
Yes, the LTC3780EG#PBF is explicitly designed for buck-boost operation where VIN equals VOUT. Its control architecture ensures seamless, glitch-free transitions between buck, buck-boost, and boost regions - maintaining regulation with <1% output deviation even during VIN crossing through VOUT in real-time applications.
LTC3780EG#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 24-SSOP (0.209", 5.30mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Output Type:
- Transistor Driver
- Function:
- Step-Up/Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck-Boost
- Number of Outputs:
- 1
- Output Phases:
- 1
- Voltage - Supply (Vcc/Vdd):
- 4V ~ 30V
- Frequency - Switching:
- 200kHz ~ 400kHz
- Duty Cycle (Max):
- 99%
- Synchronous Rectifier:
- Yes
- Clock Sync:
- No
- Serial Interfaces:
- -
- Control Features:
- Current Limit, Enable, Power Good, Soft Start
- Operating Temperature:
- -40°C ~ 85°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 24-SSOP
LTC3780EG#PBF FAQ
1.How can I place an order for LTC3780EG#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3780EG#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 LTC3780EG#PBF reliable?
The price and inventory of LTC3780EG#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3780EG#PBF is usually 5 days.
3.What payment methods are accepted for LTC3780EG#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3780EG#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3780EG#PBF?
LTC3780EG#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3780EG#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 LTC3780EG#PBF?
For technical support, including LTC3780EG#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3780EG#PBF requirements.
6.How does Aetrix verify that LTC3780EG#PBF is sourced from the original manufacturer or authorized distributors?
All LTC3780EG#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 LTC3780EG#PBF meets industry standards.
7.What is the process for return or replacement of LTC3780EG#PBF?
All LTC3780EG#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3780EG#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 LTC3780EG#PBF part is unused and in its original packaging.
Return procedure for LTC3780EG#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3780EG#PBF Tags
-
UCC28C45DR
Texas Instruments
-
UCC28C40DR
Texas Instruments
-
UCC28C43DR
Texas Instruments
-
ZXSC410E6TA
Diodes Incorporated
-
LM3524DMX/NOPB
Texas Instruments
-
LM3489MMX/NOPB
Texas Instruments
-
MIC2102YML-TR
Microchip Technology
-
LM5148RGYR
Texas Instruments
-
TL598CDR
Texas Instruments
-
LM5155DSSR
Texas Instruments
-
LM25085MYX/NOPB
Texas Instruments
-
UCC2813DTR-0
Texas Instruments
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…
