My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX5943AEEE+
- Part No.:
- MAX5943AEEE+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- OR Controllers, Ideal Diodes
- Package:
- 16-SSOP (0.154", 3.90mm Width)
- Datasheet:
-
MAX5943AEEE+.pdf
- Description:
- IC OR CTRLR N+1 16QSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,274
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX5943AEEE+ from Maxim Integrated is a FireWire/IEEE 1394™ current-limiting and low-drop ORing switch controller IC. It drives two external n-channel MOSFETs to provide hot-swap inrush control (7.5V–37V input), programmable active current limiting (±5% sensing accuracy), and bidirectional load disconnect for FireWire desktop/notebook ports and hubs.
For engineers reviewing the MAX5943AEEE+ datasheet, MAX5943AEEE+ pinout, MAX5943AEEE+ application, or MAX5943AEEE+ equivalent, key selection criteria include its 2ms default current-limit timeout, 50mV/60mV/40mV selectable trip thresholds via ILIM pin, UL-recognized FireWire protection, and QSOP-16 package compatibility with thermal and layout constraints in compact FireWire peripheral designs.
Technical Context
The MAX5943AEEE+ implements dual-MOSFET control: GATE2 regulates load current actively during overloads using fast pulldown currents (up to 1.0A peak) and a programmable 120–225ms timeout (tILIM), while GATE1 enables ultra-low-drop ORing via voltage-controlled turn-on (5–12.8mV VOR threshold) with <100ns turn-off response. Its fault management supports latched or autoretry modes via the LATCH pin.
It integrates precision current sensing (±5% VTH accuracy), ON-input programmable undervoltage lockout (6.2–6.8V), and shutdown current <10µA. All logic inputs tolerate IN-referenced voltages up to VIN + 0.3V, and internal charge pumps drive GATE1/GATE2 to 4.5–6.5V above SENSE/OUT respectively - enabling robust n-MOSFET gate control across the full 7.5–37V input range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 7.5V to 37V - supports full FireWire bus power range including legacy 12V and high-voltage 30V+ systems. |
| Current-Limit Threshold Accuracy | ±5% - ensures precise, repeatable trip points for RSENSE-based ILIMIT = VTH/RSENSE design. |
| Default Current-Limit Timeout | 2ms (TIM = IN) - provides rapid fault isolation while allowing brief inrush transients without nuisance tripping. |
| GATE2 Peak Pulldown Current | 1.0A - delivers strong gate discharge to fully turn off Q2 within sub-microsecond timescales during short-circuit events. |
| Shutdown Supply Current | <10µA - enables true low-power disable state for system-level energy budgeting and battery-backed applications. |
| ORing Turn-On Threshold | 5–12.8mV (selectable via OR_ADJ) - sets ultra-low forward-voltage drop point for Q1 enhancement, minimizing conduction loss vs. diode ORing. |
| Operating Temperature | -40°C to +85°C - qualified for industrial and extended-temperature FireWire peripheral environments. |
Pinout & Package
The MAX5943AEEE+ is housed in a 16-pin QSOP package (5.3mm × 10.2mm, 1.0mm height), optimized for thermal performance and PCB space efficiency in FireWire port modules.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| ON | Enable/UVLO control input | Drives high to activate device; configures UVLO threshold (6.2–6.8V) via resistor divider - critical for safe power sequencing. |
| FAULT | Active-low open-drain fault flag | Asserts low after current-limit timeout; latches or auto-restarts per LATCH pin setting - enables host MCU fault monitoring. |
| ILIM | Current-threshold select input | Connect to GND/IN/floating for 50mV/60mV/40mV VTH - directly sets ILIMIT = VTH/RSENSE with ±5% accuracy. |
| GATE2 | Current-limit MOSFET gate driver | Charge-pump output driving Q2 gate; delivers 1.0A peak pulldown for fast short-circuit shutdown - primary safety path. |
| GATE1 | ORing MOSFET gate driver | Charge-pump output driving Q1 gate; turns on when (VIN – VSENSE) > VOR (5–12.8mV) - enables <100ns reverse-current blocking. |
| SENSE | Negative current-sense input | Connects to low-side of RSENSE; referenced to IN for accurate differential sensing - forms core of current-limit feedback loop. |
Key Features
| Feature | Design Value |
|---|---|
| Programmable active current limit | MAX5943A-specific function: continuously regulates GATE2 to hold load current at ILIMIT = VTH/RSENSE - prevents damage during sustained overloads. |
| UL-recognized FireWire protective circuit | Meets UL® recognition requirements for FireWire/IEEE 1394™ applications - reduces certification burden for end equipment. |
| Low-drop power ORing with ultra-fast turn-off | ORing threshold as low as 5mV and <100ns GATE1 turn-off time - minimizes voltage drop and blocks reverse current faster than discrete diodes. |
| Latched or autoretry fault management | Selectable via LATCH pin: latch-off holds FAULT low until ON reset, while autoretry cycles after tOFF = 128×tILIM - supports both fail-safe and self-recovering systems. |
| Fast current-limit response to short circuits | Detects VIS > VTHF (83–93mV) and triggers IG2DF (80–200mA) or IG2DP (1.0A) pulldown - recovers from gross overloads in <100ns. |
Applications
| FireWire Desktop Port Protection | FireWire Peripheral Hot-Swap |
|---|---|
Use Scenario: Protecting a desktop PC's FireWire port from inrush and overload when connecting peripherals like camcorders or external HDDs. IC Role / Device Role / Timing Role: MAX5943AEEE+ acts as the primary current-limiting and ORing controller, managing Q1/Q2 MOSFETs to enforce safe insertion/removal timing and prevent bus voltage collapse. Use Value: Enables UL-recognized hot-swap compliance with 2ms current-limit timeout and ±5% trip accuracy - eliminating need for external fault logic or redundant protection ICs. | Use Scenario: Safely powering FireWire audio interfaces or storage docks that plug into live FireWire buses. IC Role / Device Role / Timing Role: MAX5943AEEE+ serves as the front-end power manager, providing programmable inrush control and bidirectional disconnect - critical for portable peripherals. Use Value: Delivers <10µA shutdown current and ON-input UVLO programming - extends battery life and ensures clean power-up sequencing in battery-powered FireWire devices. |
| FireWire Hub Power Management | Industrial FireWire I/O Module |
Use Scenario: Distributing power across multiple downstream FireWire ports in a hub while preventing cross-port faults. IC Role / Device Role / Timing Role: MAX5943AEEE+ controls per-port current limiting and ORing, isolating faults to individual ports via independent GATE1/GATE2 drive. Use Value: Supports 7.5–37V input range and -40°C to +85°C operation - maintains reliable port protection across varying supply conditions and ambient temperatures. | Use Scenario: Integrating FireWire connectivity into ruggedized industrial controllers requiring ESD-hardened, thermally stable power management. IC Role / Device Role / Timing Role: MAX5943AEEE+ functions as the certified FireWire interface protector, handling hot-swap, ORing, and overcurrent events without MCU intervention. Use Value: Provides 2000V HBM ESD rating and QSOP thermal profile - meets industrial reliability requirements while simplifying layout with integrated dual-gate drivers. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar FireWire current-limiting and ORing controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX5943BEEE+ | Provides circuit-breaker only (no active current regulation); default 0.5ms timeout; same pinout and package. | Suitable where fast fault clearing is prioritized over sustained current limiting - e.g., systems with low-impedance sources where overcurrent duration must be minimized. | Select MAX5943BEEE+ when active current regulation is unnecessary and faster fault response (<0.5ms) is required; verify external MOSFET SOA under unregulated short-circuit conditions. |
| TPS23753AIPWPR | IEEE 802.3af PoE controller with integrated DC-DC; no FireWire-specific ORing or UL recognition; different pinout and 20-TSSOP package. | Designed for Power over Ethernet, not FireWire; lacks FireWire voltage range (7.5–37V), OR_ADJ/VOR tuning, and UL-recognized FireWire protection. | Choose TPS23753AIPWPR only for PoE-powered FireWire bridges where auxiliary DC-DC is needed; not a functional substitute for MAX5943AEEE+ in native FireWire port designs. |
Compared with MAX5943BEEE+, the MAX5943AEEE+ adds active current regulation for sustained overload protection, while TPS23753AIPWPR targets PoE infrastructure - neither offers the UL-recognized FireWire ORing and programmable 2ms timeout of the MAX5943AEEE+.
Availability
MAX5943AEEE+ is available at Aetrix Electronics and suitable for FireWire desktop port protection, FireWire peripheral hot-swap, and FireWire hub power management requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.
Supply support for MAX5943AEEE+ 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 computing applications.
The MAX5943 product line was designed specifically for IEEE 1394/FireWire power interface protection - delivering integrated current limiting, ORing, and hot-swap control in a single QSOP package to simplify FireWire peripheral and host port design.
FAQ
What is the default current-limit timeout for MAX5943AEEE+ and how is it configured?
The MAX5943AEEE+ has a default current-limit timeout of 2ms when the TIM pin is connected to IN. This value is programmable from 1.04ms to 11.05ms by connecting an external resistor (4kΩ to 50kΩ) from TIM to GND. The timeout determines how long the device sustains active current limiting before asserting FAULT and disconnecting the load - a critical parameter for balancing inrush tolerance and fault safety in FireWire applications using MAX5943AEEE+.
How does the MAX5943AEEE+ implement active current limiting versus circuit-breaker operation?
The MAX5943AEEE+ actively regulates GATE2 to maintain constant load current at ILIMIT = VTH/RSENSE during overloads, using fast pulldown currents (IG2D, IG2DF, IG2DP) to dynamically control Q2. In contrast, MAX5943B–E variants operate as circuit breakers - holding Q2 fully enhanced until timeout, then disconnecting. Only MAX5943AEEE+ provides true active current limiting, making it uniquely suited for applications requiring sustained overload protection without thermal runaway - a defining capability of the MAX5943AEEE+.
What are the three selectable current-limit thresholds for MAX5943AEEE+ and how are they set?
The MAX5943AEEE+ supports three current-limit threshold voltages (VTH): 40mV (ILIM floating), 50mV (ILIM = GND), and 60mV (ILIM = IN). These settings directly determine ILIMIT = VTH/RSENSE with ±5% accuracy. Selecting the appropriate VTH allows designers to optimize RSENSE value for desired current trip point while maintaining measurement precision - a key configuration step for achieving accurate, repeatable current limiting in every MAX5943AEEE+ implementation.
Does MAX5943AEEE+ support bidirectional load disconnect and how is it achieved?
Yes, the MAX5943AEEE+ provides true bidirectional load disconnect by turning off both external n-channel MOSFETs controlled by GATE1 and GATE2. When a fault occurs or ON is driven low, GATE1 and GATE2 are actively pulled down, blocking current flow from IN to OUT and from OUT to IN. This capability is essential for FireWire hot-swap safety and ORing applications - ensuring the MAX5943AEEE+ fully isolates the load regardless of voltage polarity or source direction.
What is the significance of UL recognition for MAX5943AEEE+ in FireWire designs?
The UL recognition of the MAX5943AEEE+ as a FireWire/IEEE 1394™ protective circuit means it has been independently evaluated and certified to meet UL safety standards for this specific application. This reduces end-equipment certification time and cost, as designers can leverage the IC's recognized status to satisfy portions of the overall FireWire port safety requirements - a critical advantage for commercial FireWire products relying on MAX5943AEEE+ for core protection functionality.
MAX5943AEEE+ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 16-SSOP (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Type:
- N+1 ORing Controller
- FET Type:
- N-Channel
- Ratio - Input:Output:
- N:1
- Internal Switch(s):
- No
- Delay Time - ON:
- -
- Delay Time - OFF:
- 100 ns
- Current - Output (Max):
- -
- Current - Supply:
- 1.3 mA
- Voltage - Supply:
- 7.5V ~ 37V
- Applications:
- FireWire®
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-QSOP
MAX5943AEEE+ FAQ
1.How can I place an order for MAX5943AEEE+ through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX5943AEEE+ 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 MAX5943AEEE+ reliable?
The price and inventory of MAX5943AEEE+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX5943AEEE+ is usually 5 days.
3.What payment methods are accepted for MAX5943AEEE+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX5943AEEE+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX5943AEEE+?
MAX5943AEEE+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX5943AEEE+ 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 MAX5943AEEE+?
For technical support, including MAX5943AEEE+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX5943AEEE+ requirements.
6.How does Aetrix verify that MAX5943AEEE+ is sourced from the original manufacturer or authorized distributors?
All MAX5943AEEE+ 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 MAX5943AEEE+ meets industry standards.
7.What is the process for return or replacement of MAX5943AEEE+?
All MAX5943AEEE+ units undergo pre-shipment inspection (PSI). If there is an issue with MAX5943AEEE+, 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 MAX5943AEEE+ part is unused and in its original packaging.
Return procedure for MAX5943AEEE+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX5943AEEE+ Tags
-
LM66100DCKR
Texas Instruments
-
LM66200DRLR
Texas Instruments
-
LM66100DCKT
Texas Instruments
-
AP74700QW6-7
Diodes Incorporated
-
LM73100RPWR
Texas Instruments
-
LM74502DDFR
Texas Instruments
-
LM74700QDBVRQ1
Texas Instruments
-
MAX40200AUK+T
Analog Devices Inc./Maxim Integrated
-
MAX40200ANS+T
Analog Devices Inc./Maxim Integrated
-
MAX40203AUK+T
Analog Devices Inc./Maxim Integrated
-
MAX40203ANS+T
Analog Devices Inc./Maxim Integrated
-
LM74502QDDFRQ1
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…
