MAX5942A, MAX5942B IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices

Description

The MAX5942A/MAX5942B integrate a complete power IC for powered devices (PD) in a power-over-ethernet (PoE) system. The MAX5942A/MAX5942B provide a PD interface and a compact DC-DC PWM controller suitable for flyback and forward converters in either isolated or nonisolated designs.

The MAX5942A/MAX5942B PD interface complies with the IEEE™ 802.3af standard, providing the PD with a detection signature, a classification signature, and an integrated isolation switch with programmable inrush current control. These devices also feature power-mode undervoltage lockout (UVLO) with wide hysteresis and power-good status outputs.

The MAX5942A/MAX5942B also integrate all the building blocks necessary for implementing DC-DC fixed-frequency isolated power supplies. This device is a current-mode controller with an integrated high startup circuit suitable for isolated telecom/industrial voltage range power supplies. A high-voltage startup circuit allows the PWM controller to draw power directly from the 18V to 67V input supply during startup. The switching frequency is internally trimmed to 275kHz ±10%, thus reducing magnetics and filter components. The MAX5942A allows an 85% operating duty cycle and can be used to implement flyback converters. The MAX5942B limits the operating duty cycle to less than 50% and can be used in single-ended forward converters. The MAX5942A/MAX5942B are designed to work with or without an external diode bridge in front of the PD.

The MAX5942A/MAX5942B are available in 16-pin SO packages.

Key Features

Applications/Uses

Powered Device Interface
- Fully Integrated IEEE 802.3af-Compliant PD Interface
- PD Detection and Programmable Classification Signatures
- Less than 10µA Leakage Current Offset During Detection
- Integrated MOSFET for Isolation and Inrush Current Limiting
- Gate Output Allows External Control of the Internal Isolation FET
- Programmable Inrush Current Control/ULVO
- PGOOD/Active-Low PGOOD Outputs Enable PWM Controller
PWM Controller
- Wide Input Range: 18V to 67V
- Isolated (Without Optocoupler) or Nonisolated Power Supply
- Current-Mode Control
- Leading-Edge Blanking
- Internally Trimmed 275kHz ±10% Oscillator
- Soft-Start

	Computer Telephony
	Internet Appliances
	IP Phones
	Power Devices in Power-Over-Ethernet/Power-Over-MDI
	Security Cameras
	Wireless Access Nodes

Key Specifications: Powered Devices

Part Number

IEEE Compliance

PD MOSFET R_DS(ON) (Ω)

Includes PWM

Switching Frequency (kHz)

Protection Features

Programmable UVLO

RoHS Available

Package

Smallest Available Package (max w/pins) (mm²)

Operating Temp. Range (°C)

Price^**

MAX5942

802.3af

0.6

Yes

275

Programmable Inrush Current

Yes

SOIC(N)/16

-40 to +85

$2.18 @ 1k

See All Powered Devices (4)

Notes:
^**This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Ordering Information

Notes:

Other options and links for purchasing parts are listed at: http://www.maxim-ic.com/sales.
Didn't Find What You Need? Ask our applications engineers. Expert assistance in finding parts, usually within one business day.
Part number suffixes: T or T&R = tape and reel; + = RoHS/lead-free; # = RoHS/lead-exempt. More: SeeFull Data Sheet or Part Naming Conventions.
* Some packages have variations, listed on the drawing. "PkgCode/Variation" tells which variation the product uses. Note that "+", "#", "-" in the part number suffix describes RoHS status. Package drawings may show a different suffix character.

Devices: 1-16 of 16

MAX5942A

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX5942ACSE

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M-6*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX5942AESE+T

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX5942AESE+

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M+6*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX5942ACSE+T

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M+6*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX5942ACSE+

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M+6*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX5942AESE

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M-6*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX5942AESE-T

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX5942ACSE-T

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M-6*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX5942B

Free
Sample

Buy

Package:	TYPE PINS FOOTPRINT
	DRAWING CODE/VAR *

Temp

RoHS/Lead-Free?
Materials Analysis

MAX5942BESE+

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M+6*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX5942BCSE+T

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M+6*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX5942BCSE+

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M+6*

-40°C to +85°C

RoHS/Lead-Free: Lead Free
Materials Analysis

MAX5942BCSE-T

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX5942BCSE

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M-6*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX5942BESE-T

Land Pattern: Not Available

-40°C to +85°C

See data sheet

MAX5942BESE

SOIC(N);16 pin;62 mm²
Outline Drawing: 21-0041 (PDF)
Land Pattern: 90-0097 (PDF)
Use pkgcode/variation: S16M-6*

-40°C to +85°C

RoHS/Lead-Free: No
Materials Analysis

MAX5942BESE+T

Land Pattern: Not Available

-40°C to +85°C

See data sheet

Related Products

MAX5940, MAX5940A, MAX5940B IEEE 802.3af PD Interface Controller for Power-Over-Ethernet