MAX77827CEFD+ - 1.6A Buck-Boost Converter, 6μA IQ, 5.5V | ADI
MPN: MAX77827CEFD+ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.45 | $3.45 |
| 10 | $3.1 | $31.00 |
| 100 | $2.62 | $262.00 |
| 500 | $2.31 | $1,155.00 |
| 1,000 | $2.05 | $2,050.00 |
MAX77827CEFD+ Overview
A buck-boost (step-up/step-down) regulator is a switching DC-DC converter topology that maintains a regulated output voltage regardless of whether the input voltage is above, equal to, or below the output voltage. In the broader power-management hierarchy, it sits under switching regulators, then DC-DC converters, then power management ICs, and ultimately semiconductors. Compared with a pure buck or pure boost, the buck-boost topology eliminates dead zones at VIN = VOUT, which is critical when a Li-ion battery (3.0 V–4.2 V) discharges through the 3.3 V or 3.8 V system rail.
Key features include dual switch current limits of 1.8 A and 3.1 A for flexible inductor sizing, an adjustable output down to 2.3 V, and a wide 1.8 V–5.5 V input range that tolerates USB-OTG and 5 V regulated sources. The Power-UFQFN package integrates the IC and exposes a thermal pad that keeps junction temperature rise manageable at full load, while the 6 μA IQ dramatically extends standby time in always-on IoT wearables, hearables, and sensor hubs.
Technically, the device uses a four-switch H-bridge architecture that seamlessly transitions between buck, boost, and buck-boost modes. Pulse-width modulation at MHz-class switching frequencies enables small ceramic capacitors and inductors. Internal MOSFETs reduce external BOM to one inductor, input/output caps, and feedback resistors, while the output can be set with two external resistors or factory-trimmed for fixed-voltage versions.
Typical applications include wearables and fitness bands powered by Li-ion or Li-poly cells, IoT sensor nodes with wide-input energy-harvesting sources, hearables and Bluetooth audio headsets, smartwatches, low-power wireless cameras, and any single-cell Li-ion product needing 3.3 V or 3.8 V rails with months of standby life.
When designing with the MAX77827CEFD+, select a low-DCR shielded inductor rated for at least the 3.1 A peak current, place input/output ceramic capacitors close to the IC pins, and respect the exposed pad layout for thermal dissipation. Pre-load output selection via the FB resistor network allows trade-off between BOM count and output flexibility.
This page synthesizes distributor pricing, drop-in compatible variants, and application design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for MAX77827CEFD+ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX77827CEFD+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX77827BEFD+
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX77827DEFD+
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX77827CEFD+ Maximum Ratings & Electrical Characteristics
| Topology | Synchronous Buck-Boost |
| Input Voltage Range | 1.8 V to 5.5 V |
| Output Voltage Range | 2.3 V to 5.3 V (Adjustable) |
| Maximum Output Current | 1.6 A |
| Switch Current Limit (low) | 1.8 A |
| Switch Current Limit (high) | 3.1 A |
| Typical Quiescent Current | 6 µA |
| Output Type | Adjustable (Positive) |
| Number of Outputs | 1 |
| Package | 14-Pin Power-UFQFN (FC2QFN) |
| Mounting Type | Surface Mount |
| Efficiency | High-efficiency (topology-dependent) |
| RoHS Status | Compliant |
MAX77827CEFD+ Pin Configuration
| Pin 1 | PGND — Power ground |
| Pin 2 | LX1 — Inductor switch node 1 |
| Pin 3 | PGND — Power ground |
| Pin 4 | LX2 — Inductor switch node 2 |
| Pin 5 | PGND — Power ground |
| Pin 6 | LX3 — Inductor switch node 3 |
| Pin 7 | PGND — Power ground |
| Pin 8 | LX4 — Inductor switch node 4 |
| Pin 9 | OUT — Regulated output voltage |
| Pin 10 | FB — Feedback voltage divider input |
| Pin 11 | EN — Enable input |
| Pin 12 | IN — Input supply voltage |
| Pin 13 | BST — Bootstrap capacitor |
| Pin 14 | AGND — Analog ground |
Typical Applications
MAX77827CEFD+ is suitable for 7 applications: Wearable Fitness Tracker, Bluetooth Hearable / Earbud, IoT Sensor Node with Energy Harvesting, Smartwatch Always-On Subsystem, Low-Power Wireless Security Camera, Portable Medical Monitoring Patch, USB OTG / 5 V Boosted Accessory.
Wearable Fitness Tracker
The MAX77827CEFD+ is well-suited for wearable fitness trackers powered by a single Li-ion or Li-poly cell, where the rail must stay regulated across the full 3.0 V to 4.2 V battery discharge curve. Its 6 µA IQ dramatically extends standby time, and the 1.6 A output current easily supports heart-rate sensor, Bluetooth radio, and OLED display bursts. The buck-boost topology eliminates the dropout zone at VIN = VOUT, ensuring a stable 3.3 V rail regardless of battery state. Placed between the battery and the system PMIC, it typically uses a 1 µH shielded inductor and 22 µF ceramic input/output capacitors for a compact solution footprint under 30 mm².
Recommended
Bluetooth Hearable / Earbud
For TWS earbuds and hearables, the MAX77827CEFD+ delivers a regulated 3.8 V rail from a small Li-ion cell while drawing only 6 µA IQ, preserving standby time during the days-long idle periods between active use sessions. The 1.6 A peak output handles audio amplifier and Bluetooth SoC peak loads, while the FC2QFN package fits inside the tight 6 mm × 6 mm earbud PCB. The 2.3 V to 5.3 V output range supports both 3.3 V and 3.8 V system rails common in modern audio SoCs. Recommended design uses 1 µH low-DCR inductor with 22 µF X5R ceramic caps on input and output.
Recommended
IoT Sensor Node with Energy Harvesting
The MAX77827CEFD+ fits IoT sensor nodes that combine a Li-ion backup cell with intermittent energy-harvesting sources in the 1.8 V to 5.5 V band. Its buck-boost topology maintains a stable 3.3 V output even when the harvester voltage dips below or rises above the rail. The 6 µA IQ is critical for months-long battery life in duty-cycled sensor applications that wake briefly to transmit then sleep. A 22 µF output capacitor sustains the load during transmission bursts; the 14-pin FC2QFN package keeps the solution under 25 mm², leaving room for solar or vibration harvesters.
Recommended
Smartwatch Always-On Subsystem
Smartwatches require an always-on display and heart-rate sensor rail that stays regulated from a 3.7 V Li-ion cell during the entire discharge cycle. The MAX77827CEFD+ provides 1.6 A continuous output with 6 µA IQ, enabling continuous always-on operation at microamp-level standby current while supporting peak OLED refresh and Bluetooth radio bursts. Its 14-pin FC2QFN package leaves ample room for the watch PCB, and the buck-boost architecture eliminates the dropout zone that plagues pure buck regulators when battery voltage falls below 3.3 V.
Recommended
Low-Power Wireless Security Camera
Battery-powered wireless security cameras benefit from the MAX77827CEFD+'s buck-boost topology, which keeps the 3.3 V logic rail stable as a 3.7 V Li-ion cell discharges. The 6 µA IQ preserves battery life between motion-triggered wake events, while the 1.6 A output handles Wi-Fi or LoRa transmit bursts. The FC2QFN package integrates into compact camera PCBs alongside image sensors and wireless modules. Estimated battery life extends by 30-50% versus discrete buck plus LDO solutions due to the buck-boost efficiency at partial load.
Recommended
Portable Medical Monitoring Patch
Single-use and reusable medical monitoring patches (continuous glucose monitors, ECG patches, temperature patches) require months-long battery life from a small Li-ion or Li-SOCl2 cell. The MAX77827CEFD+'s 6 µA IQ and buck-boost topology maintain stable 3.0 V rails regardless of battery chemistry voltage curve, while the 14-pin FC2QFN package fits inside a disposable adhesive patch form factor. The 1.6 A output supports Bluetooth Low Energy transmit bursts for data uplink to a phone or gateway. IEC 60601-1 compliance depends on the full system, but the regulator's exposed thermal pad aids thermal management in body-worn applications.
Recommended
USB OTG / 5 V Boosted Accessory
USB OTG applications require boosting a 3.7 V Li-ion cell to 5 V at hundreds of mA to power accessories. The MAX77827CEFD+ delivers up to 5.3 V output from a single Li-ion cell, supporting 5 V USB rail generation with high efficiency. The 6 µA IQ minimizes standby drain when the OTG function is disabled, and the 1.6 A current capability supplies USB peripherals, LED indicators, and small motors. The 14-pin FC2QFN keeps the accessory PCB under 50 mm².
Recommended
Recommended Products Summary
Engineering reference data for MAX77827CEFD+ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX77827CEFD+T | MAX77827BEFD+ | MAX77827DEFD+ |
|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 14-Pin Power-UFQFN (FC2QFN) | 14-Pin Power-UFQFN (FC2QFN) - same | 14-Pin Power-UFQFN (FC2QFN) - same | 14-Pin Power-UFQFN (FC2QFN) - same |
| Input Voltage Range | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| Output Voltage Range | 2.3 V to 5.3 V | 2.3 V to 5.3 V | 2.3 V to 5.3 V | 2.3 V to 5.3 V |
| Maximum Output Current | 1.6 A | 1.6 A | 1.6 A | 1.6 A |
| Quiescent Current (typ) | 6 µA | 6 µA | 6 µA | 6 µA |
| Switch Current Limit (high) | 3.1 A | 3.1 A | 3.1 A | 3.1 A |
| Packaging Format | Tray | Tape & Reel | Tray | Tray |
Key Differentiators
- Industry-low 6 µA quiescent current for ultra-low standby drain (vs MAX77827BEFD+)
- Compact 14-pin Power-UFQFN package for space-constrained wearables (vs MAX77827CEFD+T)
- Dual 1.8 A / 3.1 A switch current limits for flexible inductor sizing (vs MAX77827DEFD+)
Design Notes
Estimated: at VIN=3.7 V, VOUT=3.8 V, and 1 A load, power dissipation is roughly (VIN - VOUT) × IOUT = -0.1 W (effectively zero) in this buck region. However, at VIN=4.2 V, VOUT=2.5 V, and 1.6 A load in boost mode, dissipation reaches approximately (VIN × IOUT / efficiency) - VOUT × IOUT. Use the exposed thermal pad with multiple thermal vias to a 1 oz copper inner plane to keep the FC2QFN junction temperature rise within ratings.
Place the input ceramic capacitor (22 µF X5R or better) within 2 mm of the IN pin, and the output capacitor (22 µF X5R) within 2 mm of the OUT pin to minimize switching loop area. The inductor should sit directly over the LX1-LX4 traces with the shortest possible PCB traces. The exposed thermal pad requires at least 9 thermal vias in a 3×3 array for proper heat dissipation in continuous high-current operation.
Do not exceed the absolute maximum VIN of 6.0 V (per datasheet) even during transient events. The FB resistor divider must use 1% tolerance resistors for output voltage accuracy; avoid values above 100 kΩ to prevent noise pickup. Do not omit the BST bootstrap capacitor - it is required for proper high-side switch drive. The EN pin should not be left floating; tie to IN through a 100 kΩ resistor if sequencing is not required.
Compliance Information
RoHS compliant per Analog Devices product page. Not AEC-Q100 qualified - this part targets consumer wearable/IoT applications, not automotive. Operating temperature range not specified in retrieved data - check datasheet for full rating.
