TPS2376DR [TI]

IEEE 802.3af PoE POWERED DEVICE CONTROLLERS;
TPS2376DR
型号: TPS2376DR
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

IEEE 802.3af PoE POWERED DEVICE CONTROLLERS

光电二极管
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data sheet  
TPS2375  
TPS2376  
TPS2377  
D−8  
PW−8  
www.ti.com............................................................................................................................................................ SLVS525BAPRIL 2004REVISED APRIL 2008  
IEEE 802.3af PoE POWERED DEVICE CONTROLLERS  
1
FEATURES  
APPLICATIONS  
VoIP Phones  
Fully Supports IEEE 802.3af Specification  
Integrated 0.58-, 100-V, Low-Side Switch  
15-kV System Level ESD Capable  
Supports Use of Low-Cost Silicon Rectifiers  
Programmable Inrush Current Control  
Fixed 450-mA Current Limit  
WLAN Access Points  
Security Cameras  
Internet Appliances  
POS Terminals  
TPS2376  
TPS2375/77  
(TOP VIEW)  
(TOP VIEW)  
Fixed and Adjustable UVLO Options  
Open-Drain, Power-Good Reporting  
Overtemperature Protection  
1
2
8
7
6
5
1
2
8
7
6
5
VDD  
VDD  
N/C  
ILIM  
ILIM  
CLASS  
DET  
CLASS  
DET  
UVLO  
3
4
3
4
PG  
PG  
RTN  
RTN  
VSS  
VSS  
Industrial Temperature Range: -40°C to 85°C  
8-Pin SOIC and TSSOP Packages  
DESCRIPTION  
These easy-to-use 8-pin integrated circuits contain all of the features needed to develop an IEEE 802.3af  
compliant powered device (PD). The TPS2375 family is a second generation PDC (PD Controller) featuring  
100-V ratings and a true open-drain, power-good function.  
In addition to the basic functions of detection, classification and undervoltage lockout (UVLO), these controllers  
include an adjustable inrush limiting feature. The TPS2375 has 802.3af compliant UVLO limits, the TPS2377 has  
legacy UVLO limits, and the TPS2376 has a programmable UVLO with a dedicated input pin.  
The TPS2375 family specifications incorporate a voltage offset of 1.5 V between its limits and the IEEE 802.3af  
specifications to accommodate the required input diode bridges used to make the PD polarity insensitive.  
Additional resources can be found on the TI Web site www.ti.com.  
RJ−45  
1
TX  
Pair  
Detect  
Classify  
Power Up & Inrush  
Data to  
Ethernet  
PHY  
2
Class 3  
Current  
Input  
Current  
DF01S  
2 Places  
R
100  
kW  
(DET)  
24.9 kW,  
V
(PG-RTN)  
1 %  
PG  
DET  
ILIM  
R
(ILIM)  
4
5
0.1mF,  
100 V  
10 %  
178 kW,  
1 %  
V
100 mF,  
100 V  
DD  
Spare  
Pair  
CLASS  
V
RTN  
7
8
RTN  
R
(ICLASS)  
357 W,  
1 %  
Spare  
Pair  
3
Note: Class 3 PD Depicted.  
PG Pullup Resistor Is Optional.  
Note: All Voltages With Respect to VSS.  
RX  
Pair  
Data to  
Ethernet PHY  
6
Figure 1. Typical Application Circuit and Startup Waveforms  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2004–2008, Texas Instruments Incorporated  
 
data sheet  
TPS2375  
TPS2376  
TPS2377  
SLVS525BAPRIL 2004REVISED APRIL 2008............................................................................................................................................................ www.ti.com  
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with  
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.  
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more  
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.  
AVAILABLE OPTIONS  
UVLO THRESHOLDS (NOMINAL)  
LOW  
PACKAGE(1)  
TA  
MARKING  
TYPE  
HIGH  
39.3 V  
2.49 V  
35.1 V  
SO-8  
TSSOP-8  
802.3af  
Adjustable  
Legacy  
30.5 V  
1.93 V  
30.5 V  
TPS2375D  
TPS2376D  
TPS2377D  
TPS2375PW  
TPS2376PW  
TPS2377PW  
2375  
2376  
2377  
-40°C to 85°C  
(1) Add an R suffix to the device type for tape and reel.  
ABSOLUTE MAXIMUM RATINGS  
over operating free-air temperature range (unless otherwise noted) (1), voltages are referenced to V(VSS)  
TPS237x  
VDD, RTN, DET, PG(2)  
-0.3 V to 100 V  
-0.3 V to 10 V  
-0.3 V to 12 V  
0 to 515 mA  
0 to 5 mA  
0 to 1 mA  
0 to 50 mA  
0 to 1 mA  
2 kV  
Voltage  
ILIM, UVLO  
CLASS  
RTN(3)  
Current, sinking  
Current, sourcing  
ESD  
PG  
DET  
CLASS  
ILIM  
Human body model  
Charged device model  
System level (contact/air) at RJ-45(4)  
500 V  
8/15 kV  
TJ  
Maximum junction temperature range  
Storage temperature range  
Internally limited  
-65°C to 150°C  
260°C  
Tstg  
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds - Green Packages  
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds - Nongreen Packages  
235°C  
(1) Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings  
only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating  
conditions” is not implied. Exposure to absolute–maximum–rated conditions for extended periods may affect device reliability.  
(2) I(RTN) = 0  
(3) SOA limited to V(RTN) = 80 V and I(RTN) = 515 mA.  
(4) Surges applied to RJ-45 of Figure 1 between pins of RJ-45, and between pins and output voltage rails per EN61000-4-2, 1999.  
DISSIPATION RATING TABLE(1)  
POWER RATING  
θJA (LOW-K)  
°C/W  
θJA (HIGH-K)  
°C/W  
(HIGH-K)  
TA = 85°C  
mW  
PACKAGE  
D (SO-8)  
238  
150  
159  
266  
251  
PW (TSSOP-8)  
258.5  
(1) Tested per JEDEC JESD51. High-K is a (2 signal – 2 plane) test board and low-K is a double sided  
board with minimum pad area and natural convection.  
2
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Copyright © 2004–2008, Texas Instruments Incorporated  
Product Folder Link(s): TPS2375 TPS2376 TPS2377  
data sheet  
TPS2375  
TPS2376  
TPS2377  
www.ti.com............................................................................................................................................................ SLVS525BAPRIL 2004REVISED APRIL 2008  
RECOMMENDED OPERATING CONDITIONS  
MIN  
0
MAX  
57  
UNIT  
V
VDD, PG, RTN  
UVLO  
Input voltage range  
0
5
V
Operating current range (sinking)  
Classification resistor(1)  
RTN  
0
350  
4420  
500  
2
mA  
CLASS  
255  
62.5  
0
(1)  
R(ILIM) Inrush limit program resistor  
k  
mA  
°C  
°C  
Sinking current  
PG  
TJ  
Operating junction temperature  
Operating free–air temperature  
-40  
-40  
125  
85  
TA  
(1) Voltage should not be eternally applied to CLASS and ILIM.  
ELECTRICAL CHARACTERISTICS  
V(VDD) = 48 V, R(DET) = 24.9 k, R(CLASS) = 255 , R(ILIM) = 178 k, and –40°C TJ 125°C, unless otherwise noted. Positive  
currents are into pins. V(UVLO) = 0 V for classification and V(UVLO) = 5 V otherwise for the TPS2376. Typical values are at 25°C.  
All voltages are with respect to VSS unless otherwise noted.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
DETECTION  
DET open, V(VDD) = V(RTN) = 1.9 V, measure  
I(VDD) + I(RTN)  
Offset current  
0.3  
4
3
µA  
µA  
DET open, V(VDD) = V(RTN) = 10.1 V, measure  
I(VDD) + I(RTN)  
Sleep current  
12  
DET leakage current  
V(DET) = V(VDD) = 57 V, measure I(DET)  
0.1  
56  
5
µA  
µA  
V(RTN) = V(VDD)  
,
V(VDD) = 1.4 V  
53.7  
395  
58.3  
R(DET) = 24.9 k,  
measure I(VDD) + I(RTN)  
I(DET)  
Detection current  
+
V(VDD) = 10.1 V  
410  
417  
µA  
CLASSIFICATION  
R(CLASS) = 4420 , 13 V(VDD) 21 V  
R(CLASS) = 953 , 13 V(VDD) 21 V  
R(CLASS) = 549 , 13 V(VDD) 21 V  
R(CLASS) = 357 , 13 V(VDD) 21 V  
R(CLASS) = 255 , 13 V(VDD) 21 V  
Regulator turns on, V(VDD) rising  
Regulator turns off, V(VDD) rising  
Hysteresis  
2.2  
10.3  
17.7  
27.1  
38.0  
10.2  
21  
2.4  
10.6  
18.3  
28.0  
39.4  
11.3  
21.9  
0.78  
2.8  
11.3  
19.5  
29.5  
41.2  
13.0  
23  
I(CLASS)  
Classification current(1)  
mA  
V(CL_ON)  
V(CU_OFF)  
V(CU_H)  
Classification lower threshold  
Classification upper threshold  
Leakage current  
V
V
0.5  
1
V
V(CLASS) = 0 V, V(VDD) = 57 V  
1
µA  
PASS DEVICE  
rDS(on)  
On resistance  
I(RTN) = 300 mA  
0.58  
1.0  
15  
V(VDD) = V(RTN) = 30 V,  
V(UVLO) = 0 V (TPS2376)  
Leakage current  
µA  
Current limit  
Inrush limit  
V(RTN) = 1 V  
405  
100  
461  
130  
515  
180  
mA  
mA  
I(LIM)  
V(RTN) = 2 V, R(ILIM) = 178 kΩ  
V(RTN) falling, R(ILIM) = 178 k, inrush  
statenormal operation  
85%  
91%  
100%  
(2)  
Inrush current termination  
R(ILIM) = 69.8 k, V(RTN-VSS) = 5 V,  
I(RTN) = 30 mA300 mA, V(VDD) increasing  
past upper UVLO  
15  
25  
2
Current rise time into inrush  
µs  
Apply load ∞Ω→20 , time measured to  
I(RTN) = 45 mA  
2.5  
1
Current limit response time  
Leakage current, ILIM  
µs  
V(VDD) = 15 V, V(UVLO) = 0 V  
µA  
(1) Classification is tested with exact resistor values. A 1% tolerance classification resistor assures compliance with IEEE 802.3af limits.  
(2) This parameter specifies the RTN current value, as a percentage of the steady state inrush current, below which it must fall to make PG  
assert (open-drain).  
Copyright © 2004–2008, Texas Instruments Incorporated  
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Product Folder Link(s): TPS2375 TPS2376 TPS2377  
data sheet  
TPS2375  
TPS2376  
TPS2377  
SLVS525BAPRIL 2004REVISED APRIL 2008............................................................................................................................................................ www.ti.com  
ELECTRICAL CHARACTERISTICS (continued)  
V(VDD) = 48 V, R(DET) = 24.9 k, R(CLASS) = 255 , R(ILIM) = 178 k, and –40°C TJ 125°C, unless otherwise noted. Positive  
currents are into pins. V(UVLO) = 0 V for classification and V(UVLO) = 5 V otherwise for the TPS2376. Typical values are at 25°C.  
All voltages are with respect to VSS unless otherwise noted.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
PG  
Latchoff voltage threshold rising  
PG deglitch  
V(RTN) rising  
9.5  
75  
10.0  
150  
10.5  
225  
0.4  
V
Delay rising and falling PG  
µs  
I(PG) = 2 mA, V(RTN) = 34 V,  
V(VDD) = 38 V, V(RTN) falling  
0.12  
V
Output low voltage  
Leakage current  
I(PG) = 2 mA, V(RTN) = 0 V, V(VDD) = 25 V, for  
TPS2376 V(UVLO) = 0 V  
0.12  
0.1  
0.4  
1
V
V(PG) = 57 V, V(RTN) = 0 V  
µA  
UVLO  
V(UVLO_R)  
V(UVLO_F)  
V(VDD) rising  
V(VDD) falling  
Hysteresis  
38.4  
29.6  
8.3  
39.3  
30.5  
8.8  
40.4  
31.5  
9.1  
TPS2375 Voltage at VDD  
TPS2376 Voltage at UVLO  
V
V
V(VDD) rising  
V(VDD) falling  
Hysteresis  
2.43  
1.87  
0.53  
34.1  
29.7  
4.3  
2.49  
1.93  
0.56  
35.1  
30.5  
4.5  
2.57  
1.98  
0.58  
36.0  
31.4  
4.8  
V(VDD) rising  
V(VDD) falling  
Hysteresis  
TPS2377 Voltage at VDD  
V
TPS2376 Input leakage, UVLO  
V(UVLO) = 0 V to 5 V  
-1  
1
µA  
THERMAL SHUTDOWN  
Shutdown temperature  
Temperature rising  
135  
°C  
°C  
Hysteresis  
20  
BIAS CURRENT  
Operating current  
I(VDD)  
240  
450  
µA  
4
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Copyright © 2004–2008, Texas Instruments Incorporated  
Product Folder Link(s): TPS2375 TPS2376 TPS2377  
data sheet  
TPS2375  
TPS2376  
TPS2377  
www.ti.com............................................................................................................................................................ SLVS525BAPRIL 2004REVISED APRIL 2008  
DEVICE INFORMATION  
FUNCTIONAL BLOCK DIAGRAM  
DET  
3
Detection  
Comparator  
12 V  
+
VDD  
8
CLASS  
2
10 V  
Regulator  
Classification  
Comparator  
22 V  
+
PG  
6
PG Comparator  
Delay  
150 mS  
1.5 V  
& 10 V  
+
R
S
R
Q
0 = Fault  
0 = Inrush  
S
Q
UVLO  
Comp.  
RTN  
5
2.5 V  
Thermal Shutdown,  
Counter, and Latch  
UVLO  
’76 Only  
+
1 = Limiting  
1
See  
Note  
Current  
Mirror  
7
45 mV  
+
EN  
1:1  
2.5 V  
Current  
Limit Amp.  
+
0
ILIM  
1
800 W  
0.08 W  
VSS  
4
Note: For the TPS2376, the UVLO comparator connects to the UVLO pin and not to the UVLO divider.  
Copyright © 2004–2008, Texas Instruments Incorporated  
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5
Product Folder Link(s): TPS2375 TPS2376 TPS2377  
data sheet  
TPS2375  
TPS2376  
TPS2377  
SLVS525BAPRIL 2004REVISED APRIL 2008............................................................................................................................................................ www.ti.com  
TERMINAL FUNCTIONS  
PIN NUMBER  
PIN NAME  
I/O  
DESCRIPTION  
TPS2375/77  
TPS2376  
Connect a resistor from ILIM to VSS to set the start-up inrush current limit.  
The equation for calculating the resistor is shown in the detailed pin  
description section for ILIM.  
ILIM  
1
1
O
Connect a resistor from CLASS to VSS to set the classification of the  
powered device (PD). The IEEE classification levels and corresponding  
resistor values are shown in Table 1.  
CLASS  
2
2
O
Connect a 24.9-kdetection resistor from DET to VDD for a valid PD  
detection.  
DET  
VSS  
RTN  
PG  
3
4
5
6
-
3
4
5
6
7
O
I
Return line on the source side of the TPS2375 from the PSE.  
Switched output side return line used as the low-side reference for the  
TPS2375 load.  
O
O
I
Open-drain, power-good output; active high.  
Used only on the TPS2376. Connect a resistor divider from VDD to VSS to  
implement the adjustable UVLO feature of the TPS2376.  
UVLO  
NC  
7
8
-
No connection  
VDD  
8
I
Positive line from the rectified PSE provided input.  
Detailed Pin Description  
The following descriptions refer to the schematic of Figure 1 and the functional block diagram.  
ILIM: A resistor from this pin to VSS sets the inrush current limit per Equation 1:  
25000  
I
+
(LIM)  
R
(ILIM)  
(1)  
where ILIM is the desired inrush current value, in amperes, and R(ILIM) is the value of the programming resistor  
from ILIM to VSS, in ohms. The practical limits on R(ILIM) are 62.5 kto 500 k. A value of 178 kis  
recommended for compatibility with legacy PSEs.  
Inrush current limiting prevents current drawn by the bulk capacitor from causing the line voltage to sag below  
the lower UVLO threshold. Adjustable inrush current limiting allows the use of arbitrarily large capacitors and also  
accommodates legacy systems that require low inrush currents.  
The ILIM pin must not be left open or shorted to VSS.  
CLASS: Classification is implemented by means of an external resistor, R(CLASS), connected between CLASS  
and VSS. The controller draws current from the input line through R(CLASS) when the input voltage lies between  
13 V and 21 V. The classification currents specified in the electrical characteristics table include the bias current  
flowing into VDD and any RTN leakage current.  
Table 1. CLASSIFICATION  
CLASS  
PD POWER (W)  
0.44 – 12.95  
0.44 – 3.84  
3.84 – 6.49  
6.49 – 12.95  
-
R(CLASS) ()  
4420 ±1%  
953 ±1%  
549 ±1%  
357 ±1%  
255 ±1%  
802.3af LIMITS (mA)  
0 - 4  
NOTE  
0
1
2
3
4
Default class  
9 - 12  
17 - 20  
26 - 30  
36 - 44  
Reserved for future use  
The CLASS pin must not be shorted to ground.  
DET: Connect a resistor, R(DET), between DET and VDD. This resistor should equal 24.9 k, ±1% for most  
applications. R(DET) is connected across the input line when V(VDD) lies between 1.4 V and 11.3 V, and is  
disconnected when the line voltage exceeds this range to conserve power. This voltage range has been chosen  
to allow detection with two silicon rectifiers between the controller and the RJ-45 connector.  
VSS: This is the input supply negative rail that serves as a local ground to the TPS2375.  
6
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Copyright © 2004–2008, Texas Instruments Incorporated  
Product Folder Link(s): TPS2375 TPS2376 TPS2377  
 
 
data sheet  
TPS2375  
TPS2376  
TPS2377  
www.ti.com............................................................................................................................................................ SLVS525BAPRIL 2004REVISED APRIL 2008  
RTN: This pin provides the switched negative power rail used by the downstream circuits. The operational and  
inrush current limit control current into the pin. The PG circuit monitors the RTN voltage and also uses it as the  
return for the PG pin pulldown transistor. The internal MOSFET body diode clamps VSS to RTN when voltage is  
present between VDD and RTN and the PoE input is not present.  
PG: This pin goes to a high resistance state when the internal MOSFET that feeds the RTN pin is enabled, and  
the device is not in inrush current limiting. In all other states except detection, the PG output is pulled to RTN by  
the internal open-drain transistor. Performance is assured with at least 4 V between VDD and RTN.  
PG is an open-drain output; therefore, it may require a pullup resistor or other interface.  
UVLO: This pin is specific to the TPS2376; it is not internally connected on the TPS2375 and TPS2377. The  
UVLO pin is used with an external resistor divider between VDD and VSS to set the upper and lower UVLO  
thresholds. The hysteresis, as measured as a percentage of the upper UVLO, is the same as the TPS2375.  
The TPS2376 enables the output when V(UVLO) exceeds the upper UVLO threshold. When current begins to flow,  
VDD sags due to cable resistance and the dynamic resistance of the input diodes. The lower UVLO threshold  
must be below the lowest voltage that the input reaches.  
The TPS2376 implements adjustable UVLO thresholds, but is otherwise functionally equivalent to the TPS2375.  
The TPS2375 offers fixed UVLO thresholds designed to maximize hysteresis while maintaining compatibility with  
the IEEE 802.3af standard. The TPS2377 offers fixed UVLO thresholds optimized for use with legacy PoE  
systems.  
VDD: This is the positive input supply to the TPS2375, which is also common to downstream load circuits. This  
pin provides operating power and allows the controller to monitor the line voltage to determine the mode of  
operation.  
Copyright © 2004–2008, Texas Instruments Incorporated  
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Product Folder Link(s): TPS2375 TPS2376 TPS2377  
data sheet  
TPS2375  
TPS2376  
TPS2377  
SLVS525BAPRIL 2004REVISED APRIL 2008............................................................................................................................................................ www.ti.com  
TYPICAL CHARACTERISTICS  
Graphs over temperature are interpolations between the marked data points.  
CLASSIFICATION TURNON  
PD DETECTION RESISTANCE  
VOLTAGE  
vs  
vs  
I(VDD) + I(RTN) IN DETECTION  
V(PI)  
TEMPERATURE  
6
5
4
3
2
11.3  
11.2  
11.1  
11.0  
35  
30  
25  
20  
15  
10  
T
A
= 125°C  
T
A
= 25°C  
Specification Limits  
1
0
T
A
= −40°C  
0
1
2
3
4
5
6
7
8
9
10 11  
−40 −20  
0
20 40 60 80 100 120  
1
3
5
7
9
11  
V
− V  
T
A
− Free-Air Temperature − °C  
V
− V  
(VDD)  
(PI)  
Figure 2.  
Figure 3.  
Figure 4.  
CLASSIFICATION TURNOFF  
PASS DEVICE  
RESISTANCE  
vs  
VOLTAGE  
vs  
I(VDD) CURRENT  
vs  
TEMPERATURE  
VDD  
TEMPERATURE  
21.94  
21.93  
21.92  
21.91  
21.90  
0.350  
0.300  
0.250  
0.200  
0.9  
0.8  
0.7  
0.6  
0.5  
0.4  
T
= 125°C  
A
T
A
= 25°C  
T
= −40°C  
A
0.150  
0.100  
−40 −20  
0
20 40 60 80 100 120  
22  
27  
32  
37  
42  
47  
52  
57  
−40 −20  
0
20 40 60 80 100 120  
T
A
− Free-Air Temperature − °C  
T
A
− Free-Air Temperature − °C  
VDD − V  
Figure 5.  
Figure 6.  
TPS2375  
Figure 7.  
TPS2375  
UVLO RISING  
vs  
TPS2376  
UVLO RISING  
vs  
UVLO FALLING  
vs  
TEMPERATURE  
TEMPERATURE  
TEMPERATURE  
39.5  
39.4  
2.489  
30.60  
30.56  
30.52  
30.48  
30.44  
30.40  
2.488  
2.487  
2.486  
2.485  
2.484  
39.3  
39.2  
−40 −20  
0
20 40 60 80 100 120  
−40 −20  
0
20 40 60 80 100 120  
−40 −20  
0
20 40 60 80 100 120  
T
A
− Free-Air Temperature − °C  
T
A
− Free-Air Temperature − °C  
T
A
− Free-Air Temperature − °C  
Figure 8.  
Figure 9.  
Figure 10.  
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TYPICAL CHARACTERISTICS (continued)  
Graphs over temperature are interpolations between the marked data points.  
TPS2376  
UVLO FALLING  
vs  
TPS2377  
UVLO RISING  
vs  
TPS2377  
UVLO FALLING  
vs  
TEMPERATURE  
TEMPERATURE  
TEMPERATURE  
35.20  
35.15  
35.10  
35.05  
35.00  
34.95  
30.65  
30.60  
30.55  
30.50  
30.45  
1.929  
1.928  
1.927  
1.926  
1.925  
1.924  
1.923  
−40 −20  
0
20 40 60 80 100 120  
−40 −20  
0
20 40 60 80 100 120  
−40 −20  
0
20 40 60 80 100 120  
T
A
− Free-Air Temperature − °C  
T
A
− Free-Air Temperature − °C  
T
A
− Free-Air Temperature − °C  
Figure 11.  
Figure 12.  
Figure 13.  
INRUSH STATE TERMINATION  
THRESHOLD  
vs  
INRUSH CURRENT  
vs  
TEMPERATURE  
CURRENT LIMIT  
vs  
TEMPERATURE  
TEMPERATURE  
440  
435  
430  
425  
350  
325  
300  
275  
250  
225  
200  
175  
150  
125  
100  
94.0  
93.5  
93.0  
92.5  
92.0  
91.5  
75 k  
125 kΩ  
178 kΩ  
91.0  
90.5  
−40 −20  
0
20 40 60 80 100 120  
−40 −20  
0
20 40 60 80 100 120  
−40 −20  
0
20 40 60 80 100 120  
T − Free-Air Temperature − °C  
A
T
A
− Free-Air Temperature − °C  
T
A
− Free-Air Temperature − °C  
Figure 14.  
Figure 15.  
Figure 16.  
PG DEGLITCH PERIOD  
vs  
TEMPERATURE  
180  
160  
140  
120  
−40 −20  
0
20 40 60 80 100 120  
T
A
− Free-Air Temperature − °C  
Figure 17.  
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APPLICATION INFORMATION  
OVERVIEW  
The IEEE 802.3af specification defines a process for safely powering a PD over a cable, and then removing  
power if a PD is disconnected. The process proceeds through three operational states: detection, classification,  
and operation. The intent behind the process is to leave an unterminated cable unpowered while the PSE  
periodically checks for a plugged-in device; this is referred to as detection. The low power levels used during  
detection are unlikely to cause damage to devices not designed for PoE. If a valid PD signature is present, then  
the PSE may optionally inquire how much power the PD requires; this is referred to as classification. The PD  
may return a default full-power signature, or one of four other choices. Knowing the power demand of each PD  
allows the PSE to intelligently allocate power between PDs, and also to protect itself against overload. The PSE  
powers up a valid PD, and then monitors its output for overloads. The maintain power signature (MPS) is  
presented by the powered PD to assure the PSE that it is there. The PSE monitors its output for the MPS to see  
if the PD is removed, and turns the port off, if it loses the MPS. Loss of MPS returns the PSE to the initial state of  
detection. Figure 18 shows the operational states as a function of PD input voltage range.  
The PD input is typically an RJ-45 (8-pin) connector, referred to as the power interface (PI). PD input  
requirements differ from PSE output requirements to account for voltage drops in the cable and margin. The  
specification uses a cable resistance of 20 to derive the voltage limits at the PD from the PSE output  
requirements. Although the standard specifies an output power of 15.4 W at the PSE output, there is only  
12.95 W available at the input of the PD due to the worst case power loss in the cable.  
The PSE can apply voltage either between the RX and TX pairs, or between the two spare pairs as shown in  
Figure 1. The applied voltage can be of either polarity. The PSE cannot apply voltage to both paths at the same  
time. The PD uses input diode bridges to accept power from any of the possible PSE configurations. The voltage  
drops associated with the input bridges cause a difference between the IEEE 802.3af limits at the PI and the  
TPS2375 specifications.  
The PSE is required to current limit between 350 mA and 400 mA during normal operation, and it must  
disconnect the PD if it draws this current for more than 75 ms. The PSE may set lower output current limits  
based on the PD advertised power requirements, as discussed below.  
The following discussion is intended as an aid in understanding the operation of the TPS2375, but not as a  
substitute for the actual IEEE 802.3af standard. Standards change and should always be referenced when  
making design decisions.  
Shut -  
down  
Normal Operation  
Classify  
Detect  
0
2.7  
10.1  
14.5  
20.5  
30  
PI Voltage (V)  
36  
57  
42  
Figure 18. IEEE 802.3 PD Limits  
INTERNAL THRESHOLDS  
In order to implement the PoE functionality as shown in Figure 18, the TPS2375 has a number of internal  
comparators with hysteresis for stable switching between the various states. Figure 19 relates the parameters in  
the Electrical Characteristics section to the PoE states. The mode labeled idle between classification and  
detection implies that the DET, CLASS, PG, and RTN pins are all high impedance.  
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PD Powered  
Idle  
Classification  
Detection  
V
(VDD)  
V
(CU_H)  
V
V
(UVLO_R)  
(UVLO_F)  
1.4V  
V
V
(CU_OFF)  
(CL_ON)  
Figure 19. Threshold Voltages  
DETECTION  
This feature of IEEE 802.3af eliminates powering and potentially damaging Ethernet devices not intended for  
application of 48 V. When a voltage in the range of 2.7 V to 10.1 V is applied to the PI, an incremental resistance  
of 25 ksignals the PSE that the PD is capable of accepting power. A PD that is capable of accepting power,  
but is not ready, may present an incorrect signature intentionally. The incremental resistance is measured by  
applying two different voltages to the PI and measuring the current it draws. These two test voltages must be  
within the specified range and be at least 1 V apart. The incremental resistance equals the difference between  
the voltages divided by the difference between the currents. The allowed range of resistance is 23.75 kto  
26.25 k.  
The TPS2375 is in detection mode whenever the supply voltage is below the lower classification threshold. The  
TPS2375 draws a minimum of bias power in this condition, while PG and RTN are high impedance and the  
circuits associated with ILIM and CLASS are disabled. The DET pin is pulled to ground during detection. Current  
flowing through R(DET) to VSS (Figure 1) produces the detection signature. For most applications, a 24.9-k, 1%,  
resistor is recommended. R(DET) can be a small, low-power resistor because it only sees a stress of about 5 mW.  
When the input voltage rises above the 11.3 V lower classification comparator threshold, the DET pin goes to an  
open-drain condition to conserve power.  
The input diode bridge incremental resistance can be hundreds of ohms at the low currents seen at 2.7 V on the  
PI. The bridge resistance is in series with R(DET) and increases the total resistance seen by the PSE. This varys  
with the type of diode selected by the designer, and it is not usually specified on the diode data sheet. The value  
of R(DET) may be adjusted downwards to accommodate a particular diode type.  
CLASSIFICATION  
Once the PSE has detected a PD, it may optionally classify the PD. This process allows a PSE to determine the  
PD power requirements in order to allot only as much power as necessary from its fixed input power source. This  
allows the PSE to power the maximum number of PDs from a particular power budget. This step is optional  
because some PSEs can afford to allot the full power to every powered port.  
The classification process applies a voltage between 14.5 V and 20.5 V to the input of the PD, which in turn  
draws a fixed current set by R(CLASS). The PSE measures the PD current to determine which of the five available  
classes (Table 1) that the PD is signalling. The total current drawn from the PSE during classification is the sum  
of bias currents and current through R(CLASS). The TPS2375 disconnects R(CLASS) at voltages above the  
classification range to avoid excessive power dissipation (Figure 18 and Figure 19).  
The value of R(CLASS) should be chosen from the values listed in Table 1 based on the average power  
requirements of the PD. The power rating of this resistor should be chosen so that it is not overstressed for the  
required 75-ms classification period, during which 10 V is applied. The PD could be in classification for extended  
periods during bench test conditions, or if an auxiliary power source with voltage within the classification range is  
connected to the PD front end. Thermal protection may activate and turn classification off if it continues for more  
than 75 ms, but the design must not rely on this function to protect the resistor.  
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UNDERVOLTAGE LOCKOUT (UVLO)  
The TPS2375 incorporates an undervoltage lockout (UVLO) circuit that monitors line voltage to determine when  
to apply power to the downstream load and allow the PD to power up. The IEEE 802.3af specification dictates a  
maximum PD turnon voltage of 42 V and a minimum turnoff voltage of 30 V (Figure 19). The IEEE 802.3af  
standard assumes an 8-V drop in the cabling based on a 20-feed resistance and a 400-mA maximum inrush  
limit. Because the minimum PSE output voltage is 44 V, the PD must continue to operate properly with input  
voltages as low as 36 V. The TPS2375 UVLO limits are designed to meet the turnon, turnoff, and hysteresis  
requirements.  
Various legacy PSE systems in the field do not meet the minimum output voltage of 44 V. The TPS2377 UVLO  
limits are designed to support these systems with a lower turnon voltage and smaller hysteresis. Although the  
TPS2377 works with compliant PSEs, it could potentially exhibit startup instabilities if the PSE output voltage  
rises slowly. The TPS2375 is recommended for applications with compliant PSEs.  
In order to provide flexibility for noncompliant designs, the TPS2376 allows the designer to program the turnon  
thresholds with a resistor divider. The hysteresis of the TPS2376, measured as a percentage of the turnon  
voltage, is similar to that of the TPS2375. To use the TPS2376, connect a resistor divider between VDD and  
VSS with the tap connected to the UVLO pin. The total divider resistance appears in parallel with the R(DET), and  
the combination of the two should equal 24.9 k. The divider ratio should be chosen to obtain 2.5 V at the UVLO  
pin when V(VDD) is at the desired turnon voltage.  
The TPS2375 uses the UVLO function to control the load through an onboard MOSFET switch. Figure 19  
graphically shows the relationships of the UVLO thresholds defined in the Electrical Characteristics section to the  
TPS2375 operational states.  
PROGRAMMABLE INRUSH CURRENT LIMIT AND FIXED OPERATIONAL CURRENT LIMIT  
Inrush limiting is beneficial for a number of reasons. First, it provides a mechanism to keep the inrush current  
below the 400 mA, 50 ms, maximum inrush allowed by the standard. Second, by reducing the level of the current  
limit below the PSE operational limit, which can be as low as the classification power divided by the PSE voltage,  
it allows an arbitrarily large bulk capacitor to be charged. Third, some legacy PSEs may not tolerate large inrush  
currents while powering their outputs up.  
The TPS2375 operational current limit protects the internal power switch from instantaneous output faults and  
current surges. The minimum operational current limit level of 405 mA is above the maximum PSE output current  
limit of 400 mA. This current limit allows the PD to draw the maximum available power and also allows the PSE  
to detect fault conditions.  
The TPS2375 incorporates a state machine that controls the inrush and operational current limit states. When  
V(VDD) is below the lower UVLO threshold, the current limit state machine is reset. In this condition, the RTN pin  
is high impedance, and at V(VDD) once the output capacitor is discharged by the downstream circuits. When  
V(VDD) rises above the UVLO turnon threshold, the TPS2375 enables the internal power MOSFET with the  
current limit set to the programmed inrush value. The load capacitor charges and the RTN pin voltage falls from  
V(VDD) to nearly V(VSS). Once the inrush current falls about 10% below the programmed limit, the current limit  
switches to the internal 450-mA operational level after a 150-µs delay. This switchover can be seen in the  
operation of PG, which goes active (open drain) after inrush terminates as seen in Figure 1. The internal power  
MOSFET is disabled if the input voltage drops below the lower UVLO threshold.  
When in the operating current-limit state, a fault on the output or a large input transient can cause the internal  
MOSFET to limit current. The RTN voltage rises above its normal operating level of less than 0.5 V while in  
current-limit state. If V(RTN) rises above 10 V for more than 150 µs, the MOSFET is latched off. The PD input  
voltage must drop below the lower UVLO threshold to clear this latch. If the RTN voltage does not exceed 10 V  
while in current-limit state, but the condition persists long enough to overheat the TPS2375, the thermal limit  
circuit activates, as described in the thermal protection section.  
Practical values of R(ILIM) lie between 62.5 kand 500 k. The pin must not be left open. An inrush level of  
140 mA, set by an R(ILIM) of 178 k, should be used with TPS2377 applications for compatibility with legacy  
systems. This same inrush current level suffices for many TPS2375 applications.  
The inrush limit, the bulk capacitor size, and the downstream dc/dc converter startup method must be chosen so  
that the converter input current does not exceed the inrush current limit while it is active. This can be achieved by  
using the PG output to enable the downstream converter after inrush finishes, by delaying the converter startup  
until inrush finishes, or by increasing the value of the inrush current limit.  
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MAINTAIN POWER SIGNATURE  
Once a valid PD has been detected and powered, the PSE uses the maintain power signature (MPS) to  
determine when to remove power from the PI. The PSE removes power from that output port if it detects loss of  
MPS for 300 ms or more. A valid MPS requires the PD to draw at least 10 mA and also have an ac impedance  
less than 26.25 kΩ in parallel with 0.05 µF. TI's reference designs meet the requirements necessary to maintain  
power.  
POWER GOOD  
The TPS2375 includes a power-good circuit that can be used to signal the PD circuitry that the load capacitor is  
fully charged. This pin is intended for use as an enable signal for downstream circuitry. If the converter tries to  
start up while inrush is active, and draws a current equal to the inrush limit, a latchup condition occurs in which  
the PD never successfully starts. Using the PG pin is the safest way to assure that there are no undesired  
interactions between the inrush limit, the converter startup characteristic, and the size of the bulk capacitor.  
The PG pin goes to an open-drain state approximately 150 µs after the inrush current falls 10% below the  
regulated value. PG pulldown current is only assured when the voltage difference between VDD and RTN  
exceeds 4 V. This is not a limiting factor because the dc/dc converter should not be able to run from 4 V. The PG  
output is pulled to RTN whenever the MOSFET is disabled or is in inrush current limiting.  
Referencing PG to RTN simplifies the interface to the downstream dc/dc converter or other circuit because it is  
referenced to RTN, not VSS. Care must be used in interfacing the PG pin to the downstream circuits. The pullup  
to VDD shown in Figure 1 may not be appropriate for a particular dc/dc converter interface. The PG pin connects  
to an internal open-drain, 100-V transistor capable of sinking 2 mA to a voltage below 0.4 V. The PG pin can be  
left open if it is not used.  
THERMAL PROTECTION  
The controller may overheat after operation in current-limit state or classification for an extended period of time,  
or if the ambient temperature becomes excessive. The TPS2375 protects itself by disabling the RTN and CLASS  
pins when the internal die temperature reaches about 140°C. It automatically restarts when the die temperature  
has fallen approximately 20°C. If this cycle occurs eight times, then the device latches off until the supply voltage  
drops below the lower classification threshold. This feature prevents the part from operating indefinitely in fault,  
and ensures that the PSE recognizes the fault condition when using dc MPS. Thermal protection is active  
whenever the TPS2375 is not in detection.  
Figure 20 shows how the TPS2375 responds when it is enabled into a short. The TPS2375 starts in the inrush  
current-limit state when the input voltage exceeds the upper UVLO limit. A power dissipation of over 5 W heats  
the die from 25°C to 140°C in approximately 400 ms. The TPS2375 then shuts down until the die temperature  
drops to about 120°C, which occurs in about 20 ms. This process repeats eight times before the TPS2375  
latches off. The PG pin is high because RTN is tied to VDD.  
V
(PI)  
= 44 V, R  
= 178 kW  
(ILIM)  
Ch1: VDD @ 50 V/div  
CH2: RTN @ 50 V/div  
CH3: V  
@ 50 V/div  
(PG)  
Iin @ 100 mA/div  
Figure 20. TPS2375 Started Into Short  
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POWER SYSTEM DESIGN  
The PSE is a power and current limited source, which imposes certain constraints on the PD power supply  
design. DC/DC converters have both a constant input power characteristic that causes them to draw high  
currents at low voltage, and they tend to go to a full input power mode during start-up that is often 25% or more  
above their rated power. Improper design of the power system can cause the PD to not start up with all  
combinations of Ethernet lines and PSE sources.  
The following guidelines should be used:  
1. Set the TPS2375 inrush to a moderate value as previously discussed.  
2. Hold the dc/dc converter off during inrush as previously discussed.  
3. The converter should have a softstart that keeps the peak input start-up current below 400 mA, and  
preferably only a modest amount over the operating current, with a 44-V PSE source and a 20-loop.  
4. If step 3 cannot be met, the bulk input capacitor should not discharge more than 8 V during converter start  
up from a 400-mA limited, 44-V source with a 20-line. Start-up must be completed in less than 50 mS  
Step 4 requires a balance between the converter output capacitance, load, and input bulk capacitance. While  
there are some cases which may not require all these measures, such as a 1-W PD with minimal converter  
output capacitance, it is always a good practice to follow them.  
AUXILIARY POWER SOURCE ORING  
Many PoE capable devices are designed to operate from either a wall adapter or PoE power. A local power  
solution adds cost and complexity, but allows a product to be used regardless of PoE availability. Attempting to  
create solutions where the two power sources coexist in a specific controlled manner results in additional  
complexity, and is not generally recommended. Figure 21 demonstrates three methods of diode ORing external  
power into a PD. Option 1 inserts power on the output side of the PoE power conversion. Option 2 inserts power  
on the TPS2375 output. Option 3 applies power to the TPS2375 input. Each of these options has advantages  
and disadvantages. The wall adapter must meet a minimum 1500-Vac dielectric withstand test voltage to the ac  
input power and to ground for options 2 and 3.  
Inserting a Diode in This Location  
With Option 2, Allows PoE To Start  
With Aux Power Present.  
~
~
+
Main  
DC/DC  
Converter  
Output  
R
(DET)  
DC/DC  
Converter  
22 µF  
DET  
ILIM  
UCC3809  
or  
UCC3813  
R
(ILIM)  
~
~
+
CLASS  
RTN  
Option 3  
R
(CLASS)  
For Option 2,  
The Capacitor Must Be  
Right At The Output  
To Control The  
Auxiliary  
Power  
Input  
Option 2  
Option 1  
Transients.  
Use only  
one option  
Optional  
Regulator  
A Full Wave Bridge  
Gives Flexibility To  
Use Supply With Either  
Polarity  
See TI Document SLVR030 For ATypical  
Application Circuit.  
Figure 21. Auxiliary Power ORing  
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Option 1 consists of ORing power to the output of the PoE dc/dc converter. This option is preferred in cases  
where PoE is added to an existing design that uses a low-voltage wall adapter. The relatively large PD  
capacitance reduces the potential for harmful transients when the adapter is plugged in. The wall adapter output  
may be grounded if the PD incorporates an isolated converter. This solution requires two separate regulators, but  
low-voltage adapters are readily available. The PoE power can be given priority by setting its output voltage  
above that from the auxiliary source.  
Option 2 has the benefits that the adapter voltage may be lower than the TPS2375 UVLO, and that the bulk  
capacitor shown can control voltage transients caused by plugging an adapter in. The capacitor size and location  
are chosen to control the amount of ringing that can occur on this node, which can be affected by additional  
filtering components specific to a dc/dc converter design. The optional diode blocks the adapter voltage from  
reverse biasing the input, and allows a PoE source to apply power provided that the PSE output voltage is  
greater than the adapter voltage. The penalty of the diode is an additional power loss when running from PSE  
power. The PSE may not be able to detect and start powering without the diode. This means that the adapter  
may continue to power the PD until removed. Auxiliary voltage sources can be selected to be above or below the  
PoE operational voltage range. If automatic PoE precedence is desired when using the low-voltage auxiliary  
source option, make sure that the TPS2375 inrush program limit is set higher than the maximum converter input  
current at its lowest operating voltage. It is difficult to use PG with the low-voltage auxiliary source because the  
converter must operate during a condition when the TPS2375 would normally disable it. Circuits may be  
designed to force operation from one source or the other depending on the desired operation and the auxiliary  
source voltage chosen. However, they are not recommended because they increase complexity and thus cost.  
Option 3 inserts the power before the TPS2375. It is necessary for the adapter to meet the TPS2375 UVLO  
turnon requirement and to limit the maximum voltage to 57 V. This option provides a valid power-good signal and  
simplifies power priority issues. The disadvantage of this method is that it is the most likely to cause transient  
voltage problems. Plugging a powered adapter in applies a step input voltage to a node that has little  
capacitance to control the dv/dt and voltage ringing. If the wall mount supply applies power to the PD before the  
PSE, it prevents the PSE from detecting the PD. If the PSE is already powering the PD when the auxiliary source  
is plugged in, priority is given to the higher supply voltage.  
ESD  
The TPS2375 has been tested using the surge of EN61000-4-2 in an evaluation module (EVM) using the circuit  
in Figure 1. The levels used were 8-kV contact discharge and 15-kV air discharge. Surges were applied between  
the RJ-45 and the dc EVM outputs, and between an auxiliary power input jack and the dc outputs. No failures  
were observed.  
ESD requirements for a unit that incorporates the TPS2375 have much broader scope and operational  
implications than those used in TI’s testing. Unit level requirements should not be confused with EVM testing that  
only validated the TPS2375.  
EXTERNAL COMPONENTS  
Transformer  
Nodes on an Ethernet network commonly interface to the outside world via an isolation transformer per IEEE  
802.3 requirements, see Figure 1. For powered devices, the isolation transformer must include a center tap on  
the media (cable) side. Proper termination is required around the transformer to provide correct impedance  
matching and to avoid radiated and conducted emissions. Transformers must be specifically rated to work with  
the Ethernet chipset, and the IEEE 802.3af standard.  
Input Diodes or Diode Bridges  
The IEEE 802.3af requires the PD to accept power on either set of input pairs in either polarity. This requirement  
is satisfied by using two full-wave input bridge rectifiers as shown in Figure 1. Silicon p-n diodes with a 1-A or  
1.5-A rating and a minimum breakdown of 100 V are recommended. Diodes exhibit large dynamic resistance  
under low-current operating conditions such as in detection. The diodes should be tested for their behavior under  
this condition. The diode forward drops must be less than 1.5 V at 500 µA and at the lowest operating  
temperature.  
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Input Capacitor  
The IEEE 802.3af requires a PD input capacitance between 0.05 µF and 0.12 µF during detection. This capacitor  
should be located directly adjacent to the TPS2375 as shown in Figure 1. A 100-V, 10%, X7R ceramic capacitor  
meets the specification over a wide temperature range.  
Load Capacitor  
The IEEE 802.3af specification requires that the PD maintain a minimum load capacitance of 5 µF. It is  
permissible to have a much larger load capacitor, and the TPS2375 can charge in excess of 470 µF before  
thermal issues become a problem. However, if the load capacitor is too large, the PD design may violate IEEE  
802.3af requirements.  
If the load capacitor is too large, there can be a problem with inadvertent power shutdown by the PSE caused by  
failure to meet the MPS. This is caused by having a long input current dropout due to a drop in input voltage with  
a large capacitance-to-load ratio. The standard gives Equation 2:  
I
  180  
(PD)  
C v  
10 mA  
(2)  
where C is the bulk capacitance in µF and I(PD) is the PD load current in mA.  
A particular design may have a tendency to cause ringing at the RTN pin during startup, inadvertent hot-plugs of  
the PoE input, or plugging in a wall adapter. It is recommended that a minimum value of 1 µF be used at the  
output of the TPS2375 if downstream filtering prevents placing the larger bulk capacitor right on the output. When  
using ORing option 2, it is recommended that a large capacitor such as a 22 µF be placed across the TPS2375  
output.  
Transient Suppressor  
Voltage transients on the TPS2375 can be caused by connecting or disconnecting the PD, or by other  
environmental conditions like ESD. The TPS2375 is specified to operate with absolute maximum voltages  
V(VDD-VSS) and V(RTN-VSS) of 100 V. A transient voltage suppressor, such as the SMAJ58A, should be installed  
after the bridge and across the TPS2375 input as shown in Figure 1. Various configurations of output filters and  
the insertion of local power sources across either the TPS2375 input or output have the potential to cause  
stresses outside the absolute maximum ratings of the device. Designers should be aware of this possibility and  
account for it in their circuit designs. For example, use adequate capacitance across the output to limit the  
magnitude of voltage ringing caused by downstream filters. Plugging an external power source across the output  
may cause ESD-like events. Some form of protection should be considered based on a study of the specific  
waveforms seen in an application circuit.  
Layout  
The layout of the PoE front end must use good practices for power and EMI/ESD. A basic set of  
recommendations include:  
1. The parts placement must be driven by the power flow in a point-to-point manner such as RJ-45 Ethernet  
transformer diode bridges TVS and 0.1-µF capacitor TPS2375 output capacitor.  
2. There should not be any crossovers of signals from one part of the flow to another.  
3. All leads should be as short as possible with wide power traces and paired signal and return.  
4. Spacing consistent with safety standards like IEC60950 must be observed between the 48-V input voltage  
rails and between the input and an isolated converter output.  
5. The TPS2375 should be over a local ground plane or fill area referenced to VSS to aid high-speed operation.  
6. Large SMT component pads should be used on power dissipating devices such as the diodes and the  
TPS2375.  
Use of added copper on local power and ground to help the PCB spread and dissipate the heat is recommended.  
Pin 4 of the TPS2375 has the lowest thermal resistance to the die.  
16  
Submit Documentation Feedback  
Copyright © 2004–2008, Texas Instruments Incorporated  
Product Folder Link(s): TPS2375 TPS2376 TPS2377  
 
PACKAGE OPTION ADDENDUM  
www.ti.com  
11-Apr-2013  
PACKAGING INFORMATION  
Orderable Device  
TPS2375D  
Status Package Type Package Pins Package  
Eco Plan Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
Top-Side Markings  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4)  
ACTIVE  
SOIC  
SOIC  
D
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
75  
Green (RoHS  
& no Sb/Br)  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
2375  
TPS2375DG4  
TPS2375DR  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
D
D
75  
Green (RoHS  
& no Sb/Br)  
2375  
2375  
2375  
2375  
2375  
2375  
2375  
2376  
2376  
2376  
2376  
2376  
2376  
2376  
2376  
2377  
SOIC  
2500  
2500  
150  
Green (RoHS  
& no Sb/Br)  
TPS2375DRG4  
TPS2375PW  
SOIC  
D
Green (RoHS  
& no Sb/Br)  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
SOIC  
PW  
PW  
PW  
PW  
D
Green (RoHS  
& no Sb/Br)  
TPS2375PWG4  
TPS2375PWR  
TPS2375PWRG4  
TPS2376D  
150  
Green (RoHS  
& no Sb/Br)  
2000  
2000  
75  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
TPS2376DG4  
TPS2376DR  
SOIC  
D
75  
Green (RoHS  
& no Sb/Br)  
SOIC  
D
2500  
2500  
150  
Green (RoHS  
& no Sb/Br)  
TPS2376DRG4  
TPS2376PW  
SOIC  
D
Green (RoHS  
& no Sb/Br)  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
SOIC  
PW  
PW  
PW  
PW  
D
Green (RoHS  
& no Sb/Br)  
TPS2376PWG4  
TPS2376PWR  
TPS2376PWRG4  
TPS2377D  
150  
Green (RoHS  
& no Sb/Br)  
2000  
2000  
75  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
11-Apr-2013  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
-40 to 85  
Top-Side Markings  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4)  
TPS2377DG4  
TPS2377DR  
ACTIVE  
SOIC  
SOIC  
D
8
8
8
8
8
8
8
75  
Green (RoHS  
& no Sb/Br)  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
CU NIPDAU  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
2377  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
D
2500  
2500  
150  
Green (RoHS  
& no Sb/Br)  
2377  
2377  
2377  
2377  
2377  
2377  
TPS2377DRG4  
TPS2377PW  
SOIC  
D
Green (RoHS  
& no Sb/Br)  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
PW  
PW  
PW  
PW  
Green (RoHS  
& no Sb/Br)  
TPS2377PWG4  
TPS2377PWR  
TPS2377PWRG4  
150  
Green (RoHS  
& no Sb/Br)  
2000  
2000  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability  
information and additional product content details.  
TBD: The Pb-Free/Green conversion plan has not been defined.  
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that  
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.  
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between  
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.  
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight  
in homogeneous material)  
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4)  
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a  
continuation of the previous line and the two combined represent the entire Top-Side Marking for that device.  
Addendum-Page 2  
PACKAGE OPTION ADDENDUM  
www.ti.com  
11-Apr-2013  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 3  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
11-Jun-2013  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
TPS2375DR  
TPS2375PWR  
TPS2376DR  
TPS2376PWR  
TPS2377DR  
TPS2377PWR  
SOIC  
TSSOP  
SOIC  
D
PW  
D
8
8
8
8
8
8
2500  
2000  
2500  
2000  
2500  
2000  
330.0  
330.0  
330.0  
330.0  
330.0  
330.0  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
6.4  
7.0  
6.4  
7.0  
6.4  
7.0  
5.2  
3.6  
5.2  
3.6  
5.2  
3.6  
2.1  
1.6  
2.1  
1.6  
2.1  
1.6  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
TSSOP  
SOIC  
PW  
D
TSSOP  
PW  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
11-Jun-2013  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
TPS2375DR  
TPS2375PWR  
TPS2376DR  
TPS2376PWR  
TPS2377DR  
TPS2377PWR  
SOIC  
TSSOP  
SOIC  
D
PW  
D
8
8
8
8
8
8
2500  
2000  
2500  
2000  
2500  
2000  
340.5  
367.0  
367.0  
367.0  
367.0  
367.0  
338.1  
367.0  
367.0  
367.0  
367.0  
367.0  
20.6  
35.0  
35.0  
35.0  
35.0  
35.0  
TSSOP  
SOIC  
PW  
D
TSSOP  
PW  
Pack Materials-Page 2  
IMPORTANT NOTICE  
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changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest  
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TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms  
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