My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX1774EEI+
- Part No.:
- MAX1774EEI+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Package:
- 28-SSOP (0.154", 3.90mm Width)
- Datasheet:
-
MAX1774EEI+.pdf
- Description:
- IC REG BCK ADJ 1.5A/2A DL 28QSOP
- Quantity:
- Payment:
- Shipping:
Inventory:138
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX1774EEI+ from Maxim Integrated is a dual high-efficiency synchronous step-down DC-DC converter with integrated backup battery switchover, designed for PDA and handheld computing power systems. It delivers up to 2A at adjustable 1.25V–5.5V (main) and 1.5A at 1.0V–5.0V (core) from a 2.7V–28V input, and includes four voltage detectors and a boost converter for backup battery regulation in a 28-pin QSOP package.
For engineers reviewing the MAX1774EEI+ datasheet, MAX1774EEI+ pinout, MAX1774EEI+ application, or MAX1774EEI+ equivalent, this page provides verified technical context, confirmed pin functions, real-world operating modes (PWM/pulse-skipping), validated efficiency curves (up to 95% main / 91% core), and documented backup switchover behavior under AC adapter loss and low-battery conditions.
Technical Context
The MAX1774EEI+ implements two independent synchronous buck regulators: the main regulator uses external P/N-channel MOSFETs driven by PDRV/NDRV with current-mode control via CS+/CS− sensing, while the core regulator integrates internal switches and is controlled through FBC feedback. Both support 100% duty cycle operation for ultra-low dropout.
It features automatic AC adapter detection (via ACI/INS), main battery switchover (MDRV-driven P-MOSFET), and backup mode activation (BKUP/BKOFF) with LXB-based step-up conversion from 0.9V–5.5V backup sources. Four comparators-LBI, DBI, ACO, LBO-monitor battery status and adapter presence with hysteresis.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Main Output Range | 1.25V–5.5V adjustable; enables direct powering of peripheral rails (e.g., +3.3V I/O, +5V USB PHY) without external DAC or resistor ladder tuning. |
| Main Load Current | Up to 2A continuous; supports high-current peripherals like LCD backlights, SD card interfaces, and wireless modules in handheld devices. |
| Core Output Range | 1.0V–5.0V adjustable; targets processor core logic (e.g., +1.8V ARM core, +3.3V DSP) with internal switching transistors eliminating external FETs. |
| Core Load Current | Up to 1.5A; sufficient for subnotebook CPU cores and memory subsystems without thermal derating at full load. |
| Input Voltage Range | 2.7V–28V; accommodates wide-input sources including single-cell Li-ion (3.0V–4.2V), multi-cell packs, and unregulated wall adapters. |
| Quiescent Current | 170µA typical; minimizes standby drain on main battery during system suspend, extending PDA runtime between charges. |
| Switching Frequency | Up to 1.25MHz; allows use of compact 4.7µH–5.4µH inductors and reduces output ripple without requiring large bulk capacitance. |
Pinout & Package
MAX1774EEI+ is packaged in a 28-pin QSOP (0.35mm pitch, 10.2mm × 5.3mm body), optimized for space-constrained handheld PCB layouts. Thermal pad is not present; power dissipation limited to 860mW at +70°C ambient.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SHDNM (Pin 1) | Main Regulator Shutdown Input | Active-low enable; when pulled low, disables main output and associated gate drivers (PDRV/NDRV), reducing system standby power. |
| SHDNC (Pin 2) | Core Regulator Shutdown Input | Independent active-low control for core rail; allows selective shutdown of processor core while maintaining peripheral power. |
| BKUP (Pin 3) | Backup Mode Status Signal | Open-drain output asserted low during backup operation; used to trigger system-level low-power states or LED indicators. |
| MDRV (Pin 4) | Main Battery Switch Driver | Drives gate of external P-channel MOSFET to connect main battery to IN when AC adapter is removed; eliminates need for discrete OR-ing controller. |
| IN (Pin 9) | Main Power Input | Primary input supply node accepting 2.7V–28V; powers CVH/CVL regulators, gate drivers, and internal logic; requires local 10µF ceramic bypass. |
| FBM (Pin 19) | Main Output Feedback | Resistive divider connection point for setting main output voltage; internal 1.25V reference enables precise ±1.5% regulation over temperature. |
| FBC (Pin 22) | Core Output Feedback | Feedback node for core regulator; references internal 1.0V bandgap (±3%) to set core rail voltage with external resistor divider. |
| LBI (Pin 17) | Low-Battery Monitor Input | Monitors main battery via resistive divider; asserts LBO when voltage drops below 1.20V threshold (50mV hysteresis), signaling safe shutdown. |
Key Features
| Feature | Design Value |
|---|---|
| Dual Synchronous Buck Architecture | Main regulator uses external P/N-FETs for flexibility and efficiency scaling; core regulator integrates switches to reduce BOM count and layout area. |
| Automatic Backup Switchover | Seamlessly transitions from AC adapter → main battery → backup battery using BKUP/BKOFF control and LXB boost stage, preventing system crash during power loss. |
| Four Independent Voltage Detectors | LBI (main battery low), DBI (dead battery), ACO (AC adapter lost), LBO (open-drain alert) provide fault-aware power sequencing without MCU intervention. |
| PWM + Pulse-Skipping Operation | Switches automatically between PWM (medium/heavy load) and pulse-skipping (light load) to maintain >85% efficiency from 1mA to full load. |
| 100% Duty Cycle Capability | Enables dropout-free operation down to VIN = VOUT + 0.25V (at 400mA), critical for maintaining +3.3V rail as Li-ion discharges from 4.2V to 3.0V. |
Applications
| Hand-Held Computers | PDAs |
|---|---|
Use Scenario: Power management in ruggedized industrial PDAs running Windows CE or Linux with dual-voltage SoC and peripheral expansion slots. IC Role / Device Role: Primary power IC delivering regulated +3.3V (peripherals) and +1.8V (ARM9 core) from single Li-ion cell or AC adapter. Use Value: Eliminates need for separate PMIC and battery switchover IC; reduces component count by 3–4 devices while enabling seamless AC/battery handoff. |
Use Scenario: Consumer PDA with touchscreen, flash memory, and IrDA requiring stable low-noise supplies and graceful shutdown on battery depletion. IC Role / Device Role: Central power controller managing main/core rails, detecting low battery (LBI/LBO), and asserting backup mode (BKUP) before brownout. Use Value: Prevents data corruption during unexpected power loss by triggering OS-initiated save-and-shutdown sequence within 10ms of LBO assertion. |
| Internet Access Tablets | POS Terminals |
Use Scenario: Compact Wi-Fi tablet with ARM Cortex-A series SoC, requiring efficient core voltage scaling and fast transient response for bursty web traffic. IC Role / Device Role: Core regulator supplies dynamic +1.2V–+1.5V to CPU; main regulator powers +3.3V RF front-end and display interface. Use Value: Pulse-skipping mode maintains >88% efficiency at 5mA idle current, extending battery life beyond 8 hours during light browsing. |
Use Scenario: Retail POS terminal with barcode scanner, thermal printer, and EMV smart-card reader operating from AC or internal LiPo battery. IC Role / Device Role: Provides isolated +5V for printer motor, +3.3V for microcontroller, and +1.8V for secure element; monitors ACI/DBI for failover readiness. Use Value: MDRV-driven battery switchover ensures uninterrupted transaction processing during AC outage; ACO signal triggers backup logging to nonvolatile memory. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-buck with backup switchover applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX8647ETJ+ | Single 2A buck + integrated charger; no core regulator or backup boost; 20-pin TQFN; lacks LBI/DBI comparators and MDRV driver. | Suitable only for single-rail portable devices with charging; cannot replace MAX1774EEI+ in dual-rail PDA designs. | Select MAX8647ETJ+ only if application requires battery charging and has no core voltage requirement or backup switchover need. |
| TPS65120RGTR | Dual buck (1.5A/1.5A) + charge pump; no backup boost; 24-pin QFN; includes I²C interface but no analog comparators or MDRV output. | Requires MCU firmware for battery monitoring; no autonomous switchover; unsuitable for AC/battery-OR applications without software control. | Choose TPS65120RGTR only when digital control and I²C configurability outweigh need for analog fault detection and hardware-level backup handoff. |
Compared with MAX8647ETJ+ and TPS65120RGTR, the MAX1774EEI+ uniquely integrates dual independent buck regulation, analog battery monitoring with open-drain alerts, and hardware-driven backup switchover-enabling fully autonomous power management in resource-constrained embedded systems without MCU dependency.
Availability
MAX1774EEI+ is available at Aetrix Electronics and suitable for hand-held computers, PDAs, and POS terminals requiring stable component supply across extended product lifecycles and varying input voltage conditions.
Supply support for MAX1774EEI+ 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
Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.
The MAX1774EEI+ belongs to Maxim's portable power management product line, engineered specifically for handheld computing platforms needing dual-rail regulation, battery autonomy, and robust fault detection without software overhead.
FAQ
What is the maximum supported input voltage for the MAX1774EEI+?
The MAX1774EEI+ supports an absolute maximum input voltage of +30V on the IN pin, with operational specification from +2.7V to +28V. This wide range enables compatibility with unregulated wall adapters, multi-cell battery packs, and automotive-derived inputs. Exceeding +30V risks permanent damage per Absolute Maximum Ratings.
Does the MAX1774EEI+ require external MOSFETs for both regulators?
No-the MAX1774EEI+ requires external P/N-channel MOSFETs only for the main regulator (driven by PDRV/NDRV), while the core regulator integrates internal switches and needs only external inductor and output capacitor. This hybrid architecture reduces BOM cost for core rail while retaining flexibility for high-current main rail design.
How does the MAX1774EEI+ handle low-battery conditions during AC adapter operation?
When the main battery voltage falls below the LBI threshold (1.20V), the MAX1774EEI+ asserts LBO but continues powering the main output from the AC adapter. Only upon AC adapter removal does it activate MDRV to switch to main battery-and if that battery is depleted, it engages the LXB-based boost converter from the backup battery. The MAX1774EEI+ never draws from main battery while AC is present.
Can the MAX1774EEI+ operate in 100% duty cycle mode, and what is its practical benefit?
Yes-the MAX1774EEI+ supports true 100% duty cycle operation, allowing the main output to remain regulated even when input voltage drops to within ~0.25V of the output (e.g., 3.3V out from 3.55V in). This eliminates dropout-related system resets during deep battery discharge and extends usable battery capacity in handheld devices.
What is the function of the BKOFF pin on the MAX1774EEI+?
The BKOFF pin disables backup mode when pulled below +0.5V. In backup operation, pulling BKOFF low forces immediate shutdown-preventing backup battery depletion when its voltage falls below safe operating level. It serves as a programmable backup cutoff, distinct from LBI/DBI which monitor main battery health. This feature is integral to MAX1774EEI+'s layered battery protection scheme.
MAX1774EEI+ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 28-SSOP (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable
- Number of Outputs:
- 2
- Voltage - Input (Min):
- 2.7V
- Voltage - Input (Max):
- 28V
- Voltage - Output (Min/Fixed):
- 1V, 1.25V
- Voltage - Output (Max):
- 5V, 5.5V
- Current - Output:
- 1.5A, 2A
- Frequency - Switching:
- 1.25MHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-QSOP
MAX1774EEI+ FAQ
1.How can I place an order for MAX1774EEI+ through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX1774EEI+ 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 MAX1774EEI+ reliable?
The price and inventory of MAX1774EEI+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX1774EEI+ is usually 5 days.
3.What payment methods are accepted for MAX1774EEI+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX1774EEI+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX1774EEI+?
MAX1774EEI+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX1774EEI+ 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 MAX1774EEI+?
For technical support, including MAX1774EEI+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX1774EEI+ requirements.
6.How does Aetrix verify that MAX1774EEI+ is sourced from the original manufacturer or authorized distributors?
All MAX1774EEI+ 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 MAX1774EEI+ meets industry standards.
7.What is the process for return or replacement of MAX1774EEI+?
All MAX1774EEI+ units undergo pre-shipment inspection (PSI). If there is an issue with MAX1774EEI+, 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 MAX1774EEI+ part is unused and in its original packaging.
Return procedure for MAX1774EEI+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX1774EEI+ 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…
