RT7402

  • IEEE802.3at and IEEE802.3af compliant
  • Maximum 30W output power
  • Input voltage range 36V to 57V
  • Integral high efficiency DC/DC converter.
  • Low output ripple and noise
  • High performance with low price
  • Short-circuit protection
  • Transformer isolation ,1000V isolation (input to output)
  • Easy to use, with a minimum number of external components.
  • IEC 61000-4-2 Level 4 (8KV/15KV) ESD protection
  • IEC 61000-4-5 Level 3 SURGE LEVEL :10/700μs 40ohm 4KV---Optional

Related products

 
 

RT7402

  30W POE PD Module ( Isolation Model)

Product Description

Version

Date

Author

Approved By

Remarks

 RT7402V2.0

2016/6/02

LI xiao yan

Rock

 

 RT7402V4.2

2017/6/02

LI xiao yan

Rock

 

 RT7402V5.0

2020/6/02

LI xiao yan

Rock

 

 

 

 

 

 

© 2014 Shenzhen Ring&tone  Electronic Technology Co., Ltd. All rights reserved.

This document contains proprietary information of ring&tone and is not to be disclosed or used without the prior written permission of ring&tone.

Due to update and improvement of ring&tone products and technologies, information in this document is subjected to change without notice.

Features

  • IEEE802.3at and IEEE802.3af compliant
  • Maximum 30W output power
  • Input voltage range 36V to 57V
  • Integral high efficiency DC/DC converter.
  • Low output ripple and noise
  • High performance with low price
  • Short-circuit protection
  • Transformer isolation ,1000V isolation (input to output)
  • Easy to use, with a minimum number of external components.
  • IEC 61000-4-2 Level 4 (8KV/15KV) ESD protection
  • IEC 61000-4-5 Level 3 SURGE LEVEL :10/700μs 40ohm 4KV---Optional

Applications

  • IP Cameras
  • Wireless access point
  • Security and alarm systems
  • VOIP telephone
  • Point of sale network terminal equipment 

Description

The RT7402 series of modules are designed to extract power from a conventional

twisted pair Category 5 Ethernet cable, conforming to the IEEE 802.3af and IEEE 802.3at    Power-over-Ethernet(PoE) standard.

The RT7402 signature and control circuit provides the PoE compatibility signature and

power classification required by the Power Sourcing Equipment (PSE) before applying up

to 30W power to the port.

The DC/DC converter operates over a wide input voltage range and provides a regulated

output. The DC/DC converter also has built-in short-circuit output protection.

    

  • RT7402 Product Selector

 

Part Number

Nominal Output

Maximum Output Power*

Surge Level

CM DM

Rectifier bridge Integrated

Package

RT7402(DIPA)

12V 2A

30W

 

YES

DIP-A

RT7402(DIPB)

12V 2A

30W

 

YES

DIP-B

RT7402S

12V 2A

30W

 

NO

DIP-A

RT7402S-4KV

12V 2A

30W

4KV

NO

DIP-A

RT7402-4KV

12V 2A

30W

4KV

YES

DIP-A

RT7402-24v

24V 1A

30W

 

YES

DIP-A

*At 25°C with VIN = 48V

** Maximum Output Power: means it not could be operated in continuous stage .only short-term of Boot up/Heavy loading

  • Pin Description:

Pin #

Name

Description

1

VA1

RX Input (1). This input pin is used in conjunction with VA2 and

connects to the centre tap of the transformer connected to pins 1

& 2 of the RJ45 connector (RX) - it is not polarity sensitive.

VIN+ (only RT7402S)

2

VA2

TX Input (2). This input pin is used in conjunction with VA1 and

connects to the centre tap of the transformer connected to pins 3

& 6 of the RJ45 connector (TX) - it is not polarity sensitive.

VIN- (only RT7402S)

3

VB1

Direct Input (1). This input pin is used in conjunction with VB2 and connects to pin 4 & 5 of the RJ45 connector - it is not polarity

sensitive.

4

VB2

Direct Input (2). This input pin is used in conjunction with VB1 and connects to pin 7 & 8 of the RJ45 connector - it is not polarity

sensitive.

5

CAP+

Internal rectifier bridge output +   or Not connected

6

CAP-

Internal GND         or Not connected

7

-VDC

 

DC Return. This pin is the return path for the +VDC output.

8

9

+VDC

DC Output. This pin provides the regulated output from the DC/DC converter.

10

 

 

  • Absolute Maximum Ratings

 

Parameter

Symbol

Min

Max

Units

1

DC Supply Voltage

VCC

-0.3

60

V

2

DC Supply Voltage Surge for 1ms

VSURGE

-0.6

80

V

3

Storage Temperature

TS

-40

100

OC

Note 1: Exceeding the above ratings may cause permanent damage to the product. Functional operation under these conditions is not implied. Maximum ratings assume free airflow.

  • Recommended Operating Conditions

 

Parameter

Symbol

Min

Typ

Max

Units

1

Input Supply Voltage1

VIN

36

54

57

V

2

Under Voltage Lockout

VLOCK

30

 

36

V

3

Operating Temperature2

TOP

-20

25

70

Ta / OC

 

 

4

Operating Temperature

30W Continuous

24W Continuous

14W Continuous

 

 

TOP

 

 

 

-20

 

 

 

25

 

50

70

85

 

 

 

Ta / °C

Note 1: With minimum load

     2: See Section Operating Temperature Range

      ** Extended use close to, or at the maximum operating temperature can reduce the life time of the device.

  • DC Electrical Characteristics

 

DC Characteristic

Sym

Min

Typ1

Max

Units

Test Comments

1

Nominal Output Voltage

+VDC

11.5

12.0

12.5

V

 

2

Line Regulation

VLINE

 

0.1

 

%

@ 50% Load

3

Load Regulation

VLOAD

 

1

 

%

@ VIN=48V

4

Output Ripple and Noise

VRN

 

180

 

mVp-p

@ Max load2

5

Minimum Load

RLOAD

200

 

 

mA

 

6

Short-Circuit Duration3

TSC

 

 

sec

 

7

Efficiency @ 80% Load

EFF

 

87

 

%

 

8

Isolation Voltage (I/O)

VISO

 

1500

 

VPK

Impulse Test

9

Temperature Coefficient

TC

 

0.02

 

%

Per OC

 

Note 1: Typical figures are at 25°C with a nominal 48V supply and are for design aid only. Not Guaranteed

     2: The output ripple and noise can be reduced with an external filter, see application note.

     3: Continuous short circuit duration is applicable at 25'C ambient temperature in free air. At higher temperatures or with restricted

        airflow (e.g. in a sealed enclosure) the duration will need to be limited to avoid overheating.

  • RT7402 Typical Connection Diagram:
  • RT7402S Typical Connection Diagram:
    • Power Classification
  • The RT7402 classification is fixed at Class 4, this means that an IEEE802.3at Type 1 or an IEEE802.3af PSE will default to Class 0. However an IEEE802.3at PSE will recognise the Class 4 as a Type 2 PD.

     

    • AT Detection

    AT-DET output pin which is used to detect a Two Event Physical Layer classification as described in IEEE802.3at. If required the AT-DET pin can be connected directly to an opto-coupler.

    If the detects a Two Event Physical Layer classification, the (AT True) switch will close and Opto1 will turn ON. Opto1 will be connected across the isolation barrier and the output collector can be connected to a controller (with a pull-up resistor connected to the controller’s power rail). When Opto1 is ON the collector (output) will be Logic 0, the controller will then know that the PSE is capable of delivering over 15.4W. To complete the protocol the controller should then confirm that it is a Type 2 PD over the Data Link Layer*.

     If the detects a Single Event Physical Layer classification, Opto1 will be OFF and the output collector will be Logic 1 (via pull-up resistor). The controller should then assume that the PSE is limited to delivering up to 15.4W.

    If the PSE does not support the Physical Layer classification, Opto1 will be OFF. The RT7402 will operate with non IEEE802.3at compliant POE+ PSE’s.

    *Note: There are several PSEs (including Cisco) that will only delivery ≤15.4W until they receive Type 2 PD confirmation, over the Data Link Layer.