RT7406
The RT7406 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 RT7406 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.
The RT7406 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 RT7406 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.
Related products
RT7406
30W POE PD Module ( Isolation Model)
Product Description
Version
Date
Author
Approved By
Remarks
RT7406V1.1
2018/11/10
LI xiao yan
Rock
Base on RT7402V7.0
RT7406V1.1 3R
2020/4/22
LI xiao yan
Rock
Screw hole modification
© 2020 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：
Applications：
Description：
The RT7406 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 RT7406 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.
Part Number
Nominal Output
Maximum Output Power*
AT DET
Marking
Package
RT7406 V1.1 3R
12V 2A
30W
NO
RT7406
2.0CON
*At 25°C with VIN = 48V
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.
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.
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
-VDC
DC Return. This pin is the return path for the +VDC output.
6
7
+VDC
DC Output. This pin provides the regulated output from the DC/DC converter.
8
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.
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 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
10
Load inrush current capability
5
8
A@5ms
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.
The RT7406 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-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 RT7406 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.
