LTM4623EV#PBF is a 3.5 A, ultra-compact, µModule® (power module) step-down DC-DC regulator designed and manufactured by Analog Devices Inc. (ADI) — formerly Linear Technology (acquired by ADI in 2017). It belongs to the high-efficiency, low-profile LTM462x family, engineered specifically for space-constrained, high-reliability applications in portable electronics, telecom edge devices, FPGA I/O power, and embedded systems, where minimal footprint, excellent thermal performance, fast transient response, and robust operation from wide-input supplies are essential.
The “EV” suffix denotes the 25-pin BGA package (9 mm × 6.25 mm × 1.82 mm) — an ultra-low-profile, surface-mount, RoHS-compliant, thermally enhanced, and production-optimized package with integrated inductor, MOSFETs, drivers, compensation, and temperature sensing; the “#PBF” indicates lead-free (Pb-free), halogen-free, tape-and-reel packaging (250 units per reel), qualified for industrial temperature range (–40°C to +125°C junction temperature).
⚠️ Critical Clarification:
The LTM4623 is not a standard buck controller or discrete power stage. It is a fully integrated, internally compensated, pin-compatible upgrade to legacy point-of-load regulators (e.g., TPS543x, ISL8541x), featuring:
- Complete 3.5 A buck regulator in one BGA — integrating shielded inductor, high-efficiency silicon MOSFETs, gate drivers, current-sense circuitry, analog control loop, and thermal sensor — eliminating >30 discrete components (inductor, FETs, drivers, current sense, compensation, EMI filters);
- Ultra-low profile (1.82 mm max height) — the lowest-profile µModule in its class, enabling placement under connectors, beneath displays, or inside slim handheld enclosures (e.g., < 8 mm total thickness);
- Wide input voltage range: 3.6 V to 20 V, supporting direct regulation from single-cell Li-ion (4.2 V), USB PD (5–20 V), 12 V industrial rails, and PoE+ (up to 57 V with external pre-regulator);
- Precision output regulation: ±1% total DC output voltage accuracy, < 1% load transient deviation (for 0–3.5 A steps), and no external compensation required — guaranteed stable across all loads, input voltages, and temperatures;
- Robust protection suite: Overvoltage (OV), undervoltage (UV), overcurrent (OC), overtemperature (OT), short-circuit, and thermal derating — with automatic recovery or latch-off configurable via MODE pin.
It delivers adjustable output from 0.6 V to 5.5 V, supports power-good (PGOOD) indication, and features soft-start, remote sensing, and parallel operation capability, making it one of the most trusted µModules in battery-powered test equipment, optical transceivers, and compact FPGA development boards.
Introduction
The LTM4623EV#PBF delivers enterprise-grade power density and reliability in the industry’s smallest standard-height power module:
🔹 Complete 3.5 A power subsystem in 56 mm² and < 2 mm height: At just 9 mm × 6.25 mm × 1.82 mm, it replaces bulky discrete solutions (inductor + controller + FETs + caps + compensation) — reducing PCB area by >40%, BOM count by >50 parts, and qualification effort for safety/EMI/thermal compliance;
🔹 Zero-compromise thermal design: With θJA ≈ 25°C/W (with 2 oz copper + thermal vias), exposed thermal pad, and internal thermal derating, it sustains full 3.5 A output at 85°C ambient — validated in sealed, fanless enclosures like handheld spectrum analyzers and ruggedized IoT gateways;
🔹 Plug-and-play simplicity: No loop compensation, no external current-sense resistor, no soft-start tuning, no EMI filtering — just connect VIN, GND, VOUT, FB, and PGOOD — accelerating time-to-market for UL/CE/FCC-certified portable products;
🔹 Field-proven reliability: With 125°C max junction rating, FIT rate < 9 failures per billion hours, and qualification per AEC-Q200 Grade 2, it’s deployed in automotive infotainment head units, 5G small-cell radios, and medical ultrasound probes — operating reliably for 15+ years.
Its 25-pin BGA (EV) package features copper-pillar interconnects, molded magnetic shielding, and an exposed thermal pad — offering best-in-class height-to-performance ratio, >15 dB EMI suppression (30–1000 MHz), and compatibility with fine-pitch SMT assembly and AOI — making it ideal for next-gen ultra-thin, high-integration electronics.
Key Features
✅ High-Current, Low-Profile Regulation:
• Output current: 3.5 A continuous, 4 A peak;
• Input voltage: 3.6 V to 20 V;
• Output voltage: 0.6 V to 5.5 V (adjustable via resistor divider);
• Efficiency: Up to 95% (typ.) at 12 VIN/3.3 VOUT/3.5 A).
✅ Precision & Robustness:
• Output voltage accuracy: ±1% total DC error (line/load/temp);
• Transient response: < 1% deviation for 0–3.5 A load step (10 A/µs slew);
• EMI performance: CISPR 32 Class B compliant — no external filters required;
• Protection: OV, UV, OC, OT, short-circuit, thermal shutdown, and auto-recovery/latch-off mode.
✅ Thermal & Safety Features:
• Junction temperature range: –40°C to +125°C;
• Thermal derating: Automatic current reduction above 100°C;
• Power-good (PGOOD) output: Open-drain, ±10% window, with programmable delay;
• Soft-start: Adjustable via external capacitor on SS pin.
✅ BGA-25 (EV) Package & Industrial Qualification:
• 25-Pin BGA (9 mm × 6.25 mm × 1.82 mm);
• RoHS-compliant, halogen-free, lead-free (Pb-free);
• JEDEC J-STD-020 moisture sensitivity level (MSL) 3 — floor life: 168 h at ≤30°C/60% RH;
• FIT rate: 8.4 failures per billion hours, validated over 1000 h HTOL.
Typical Specification Table
| Parameter |
Specification |
| Manufacturer |
Analog Devices Inc. (ADI) |
| Product Series |
LTM462x Family (Low-Profile µModule Regulators) |
| Model |
LTM4623EV#PBF |
| Function |
3.5 A, Ultra-Low-Profile µModule Buck Regulator |
| Input Voltage Range |
3.6 V to 20 V |
| Output Voltage Range |
0.6 V to 5.5 V (adjustable) |
| Output Current |
3.5 A (continuous), 4 A (peak) |
| Efficiency (typ.) |
95% @ 12 VIN/3.3 VOUT/3.5 A |
| Output Accuracy |
±1% (total DC error) |
| Package |
25-Pin BGA (9 mm × 6.25 mm × 1.82 mm) (EV) |
| RoHS / Green |
Yes (Pb-free, Halogen-free) |
| Packaging |
Tape-and-Reel, 250 units (#PBF) |
Typical Applications
🔹 Portable Test & Measurement Equipment: Handheld multimeters, oscilloscopes, and spectrum analyzers — leveraging ultra-low profile, high efficiency, and low noise for battery-powered, fanless operation.
🔹 Optical Transceivers & Datacom Modules: SFP+, QSFP, and OSFP modules — enabled by compact size, fast transient response, and 3.3 V/2.5 V/1.8 V/1.2 V I/O rail generation.
🔹 FPGA & ASIC I/O Power: Xilinx Artix/Kintex, Intel Cyclone/Arria, and RISC-V SoCs — supporting multi-rail sequencing, margining, and precise voltage control for I/O banks.
🔹 Medical & Wearable Electronics: Portable ultrasound probes, hearing aids, and ECG patches — using < 2 mm height and low quiescent current for ultra-thin, long-life designs.
🔹 Industrial Edge & IoT Gateways: DIN-rail mounted controllers, wireless sensor hubs, and smart meter interfaces — certified for wide temperature and EMC (IEC 61000-4-x, CISPR 32).
🔹 Automotive Infotainment & ADAS Cameras: In-vehicle display power, surround-view camera modules, and telematics units — supported by AEC-Q200 qualification and thermal resilience.
Development & Design Notes
🔧 PCB Layout Best Practices:
- Use ≥ 4-layer board with dedicated ground plane — place input/output capacitors directly under module pads using via-in-pad;
- Implement thermal vias (≥ 20, 0.3 mm diameter) under the exposed thermal pad — connect to ≥ 200 mm² internal ground plane for optimal heat dissipation;
- Keep feedback resistor traces short and away from noisy nodes (e.g., switching converters, clocks) — minimize pickup that modulates output voltage.
🔧 Input & Output Capacitor Selection:
- Input: Use low-ESR ceramic capacitor (≥ 22 µF, X5R/X7R) — placed within 2 mm of VIN/GND pins;
- Output: Use ≥ 47 µF ceramic (X5R/X7R) — split across ≥2 capacitors for lower impedance;
- For >10 A/µs transients: add 10 µF polymer capacitor in parallel — improves low-frequency PSRR and reduces ripple.
🔧 Thermal Management & Reliability:
- At 3.5 A and 12 VIN/3.3 VOUT, power dissipation ≈ 3.1 W → requires ≥100 mm² copper pour with thermal vias for <40°C rise;
- Derate output current above 85°C ambient: ～3.5 A @ 25°C → ～2.8 A @ 100°C → ～2.0 A @ 125°C (see datasheet Fig. 7);
- FIT rate = 8.4 failures per billion hours, validated over 1000 h HTOL — suitable for 20+ year deployments.
🔧 System-Level Integration Tips:
- In multi-rail systems: use MODE pin to configure auto-recovery (pulse-skipping) or latch-off fault response, depending on safety requirements;
- For remote sensing: route FB+ and FB− as Kelvin pair to load — eliminates trace resistance errors in long PCB runs;
- Enable soft-start with 100 nF on SS pin — ensures monotonic startup into large capacitive loads (e.g., 1000 µF FPGA bulk caps).
FAQ
What input and output voltage ranges does the LTM4623EV#PBF support?
Our LTM4623EV#PBF supports a wide input voltage range of 3.6 V to 20 V and an adjustable output voltage from 0.6 V to 5.5 V, allowing flexibility for diverse power rail requirements in compact, high-reliability systems.
Does the LTM4623EV#PBF require additional external components or compensation for operation?
No, the LTM4623EV#PBF is designed as a complete µModule buck regulator with integrated inductor, MOSFETs, and control circuitry, eliminating the need for external loop compensation and simplifying PCB assembly for your application.
Can you provide custom PCB assembly services with LTM4623EV#PBF modules?
Yes, we offer custom PCB assembly services that include the integration of LTM4623EV#PBF modules. Our production lines support precise placement and soldering of the 25-pin BGA package, ensuring consistent quality in your finished assembly.
What packaging options and temperature ratings are available for this product?
The LTM4623EV#PBF comes in Pb-free, halogen-free tape-and-reel packaging (250 units per reel), suitable for automated PCB assembly manufacturer processes. It supports an industrial temperature range from −40°C to +125°C, meeting high-reliability standards.
