Texas Instruments TPS2376PWRG4, TPS2376 Datasheet

D−8 PW−8

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FEATURES APPLICATIONS

1

2
3
4

5

6

7

8

VSS

CLASS UVLO

DET

RTN

PG

VDD

ILIM

1

2
3
4

5

6

7

8

VSS

CLASS N/C

DET

RTN

PG

VDD

ILIM

TPS2375/77
(TOP VIEW)

TPS2376

(TOP VIEW)

DESCRIPTION

TPS2375

SMAJ58A

Data to

Ethernet PHY

VDD

VSS

CLASS

DET

RTN

PG

Data to

Ethernet

PHY

1

3

6

4
5

7
8

TO DC/DC

CONVERTER

ILIM

2

RJ−45

DF01S

2 Places

Note: Class 3 PD Depicted.
PG Pullup Resistor Is Optional.

TX

Pair

RX

Pair

Spare

Pair

Spare

Pair

V

DD

Input

Current

V

RTN

V

Detect Classify

Power Up & Inrush

Class 3

(PG-RTN)

100

k

100 V

100 F,

R

(DET)

24.9 k
1 %

R

(ILIM)

178 k
1 %

R

(ICLASS)

357 
1 %

100 V

0.1F,

10 %

Note: All Voltages With Respect to VSS.

Current

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

IEEE 802.3af PoE POWERED DEVICE CONTROLLERS

• VoIP Phones

• Fully Supports IEEE 802.3af Specification

• WLAN Access Points

• Integrated 0.58- Ω , 100-V, Low-Side Switch

• Security Cameras

• 15-kV System Level ESD Capable

• Internet Appliances

• Supports Use of Low-Cost Silicon Rectifiers

• POS Terminals

• Programmable Inrush Current Control

• Fixed 450-mA Current Limit

• Fixed and Adjustable UVLO Options

• Open-Drain, Power-Good Reporting

• Overtemperature Protection

• Industrial Temperature Range: -40 ° C to 85 ° C

• 8-Pin SOIC and TSSOP Packages

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.

Figure 1. Typical Application Circuit and Startup Waveforms

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.

Copyright © 2004, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.

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AVAILABLE OPTIONS

ABSOLUTE MAXIMUM RATINGS

DISSIPATION RATING TABLE

(1)

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

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.

UVLO THRESHOLDS (NOMINAL) PACKAGE

(1)

T

A

MARKING

TYPE LOW HIGH SO-8 TSSOP-8

802.3af 30.5 V 39.3 V TPS2375D TPS2375PW 2375

-40 ° C to 85 ° C Adjustable 1.93 V 2.49 V TPS2376D TPS2376PW 2376
Legacy 30.5 V 35.1 V TPS2377D TPS2377PW 2377

(1) Add an R suffix to the device type for tape and reel.

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

Voltage ILIM, UVLO -0.3 V to 10 V

CLASS -0.3 V to 12 V
RTN

(3)

0 to 515 mA

Current, sinking PG 0 to 5 mA

DET 0 to 1 mA
CLASS 0 to 50 mA

Current, sourcing

ILIM 0 to 1 mA
Human body model 2 kV

ESD Charged device model 500 V

System level (contact/air) at RJ-45

(4)

8/15 kV

T

J

Maximum junction temperature range Internally limited

T

stg

Storage temperature range -65 ° C to 150 ° C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds - Green Packages 260 ° C
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.

POWER RATING

θJA(LOW-K) θJA(HIGH-K) (HIGH-K)

PACKAGE

° C/W ° C/W TA= 85 ° C

mW

D (SO-8) 238 150 266

PW (TSSOP-8) 258.5 159 251

(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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RECOMMENDED OPERATING CONDITIONS

ELECTRICAL CHARACTERISTICS

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

MIN MAX UNIT

VDD, PG, RTN 0 57 V

Input voltage range

UVLO 0 5 V
Operating current range (sinking) RTN 0 350 mA
Classification resistor

(1)

CLASS 255 4420 Ω

R

(ILIM)

Inrush limit program resistor

(1)

62.5 500 k Ω

Sinking current PG 0 2 mA

T

J

Operating junction temperature -40 125 ° C

T

A

Operating free–air temperature -40 85 ° C

(1) Voltage should not be eternally applied to CLASS and ILIM.

V

(VDD)

= 48 V, R

(DET)

= 24.9 k Ω , R

(CLASS)

= 255 Ω , R

(ILIM)

= 178 k Ω , 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

Offset current 0.3 3 µA

I

(VDD)

+ I

(RTN)

DET open, V

(VDD)

= V

(RTN)

= 10.1 V, measure

Sleep current 4 12 µA

I

(VDD)

+ I

(RTN)

DET leakage current V

(DET)

= V

(VDD)

= 57 V, measure I

(DET)

0.1 5 µA

V

(RTN)

= V

(VDD)

, V

(VDD)

= 1.4 V 53.7 56 58.3 µA

R

(DET)

= 24.9 k Ω ,

Detection current

measure I

(VDD)

+ I

(RTN)

+

V

(VDD)

= 10.1 V 395 410 417 µA

I

(DET)

CLASSIFICATION

R

(CLASS)

= 4420 Ω , 13 ≤ V

(VDD)

≤ 21 V 2.2 2.4 2.8

R

(CLASS)

= 953 Ω , 13 ≤ V

(VDD)

≤ 21 V 10.3 10.6 11.3

I

(CLASS)

Classification current

(1)

R

(CLASS)

= 549 Ω , 13 ≤ V

(VDD)

≤ 21 V 17.7 18.3 19.5 mA

R

(CLASS)

= 357 Ω , 13 ≤ V

(VDD)

≤ 21 V 27.1 28.0 29.5

R

(CLASS)

= 255 Ω , 13 ≤ V

(VDD)

≤ 21 V 38.0 39.4 41.2

V

(CL_ON)

Classification lower threshold Regulator turns on, V

(VDD)

rising 10.2 11.3 13.0 V

V

(CU_OFF)

Regulator turns off, V

(VDD)

rising 21 21.9 23 V

Classification upper threshold

V

(CU_H)

Hysteresis 0.5 0.78 1 V

Leakage current V

(CLASS)

= 0 V, V

(VDD)

= 57 V 1 µA

PASS DEVICE

r

DS(on)

On resistance I

(RTN)

= 300 mA 0.58 1.0 Ω

V

(VDD)

= V

(RTN)

= 30 V, 15

Leakage current µA

V

(UVLO)

= 0 V (TPS2376)

Current limit V

(RTN)

= 1 V 405 461 515 mA

I

(LIM)

Inrush limit V

(RTN)

= 2 V, R

(ILIM)

= 178 k Ω 100 130 180 mA

V

(RTN)

falling, R

(ILIM)

= 178 k Ω , inrush 85% 91% 100%

Inrush current termination

(2)

state → normal operation
R

(ILIM)

= 69.8 k Ω , V

(RTN-VSS)

= 5 V, 15 25

Current rise time into inrush I

(RTN)

= 30 mA → 300 mA, V

(VDD)

increasing µs

past upper UVLO
Apply load ∞ Ω → 20 Ω , time measured to 2 2.5

Current limit response time µs

I

(RTN)

= 45 mA

Leakage current, ILIM V

(VDD)

= 15 V, V

(UVLO)

= 0 V 1 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).

3

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TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

ELECTRICAL CHARACTERISTICS (continued)

V

(VDD)

= 48 V, R

(DET)

= 24.9 k Ω , R

(CLASS)

= 255 Ω , R

(ILIM)

= 178 k Ω , 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 V

(RTN)

rising 9.5 10.0 10.5 V

PG deglitch Delay rising and falling PG 75 150 225 µs

I

(PG)

= 2 mA, V

(RTN)

= 34 V, 0.12 0.4

V

V

(VDD)

= 38 V, V

(RTN)

falling

Output low voltage

I

(PG)

= 2 mA, V

(RTN)

= 0 V, V

(VDD)

= 25 V, for 0.12 0.4

V

TPS2376 V

(UVLO)

= 0 V

Leakage current V

(PG)

= 57 V, V

(RTN)

= 0 V 0.1 1 µA

UVLO

V

(UVLO_R)

V

(VDD)

rising 38.4 39.3 40.4

V

(UVLO_F)

TPS2375 Voltage at VDD V

(VDD)

falling 29.6 30.5 31.5 V
Hysteresis 8.3 8.8 9.1
V

(VDD)

rising 2.43 2.49 2.57

TPS2376 Voltage at UVLO V

(VDD)

falling 1.87 1.93 1.98 V
Hysteresis 0.53 0.56 0.58
V

(VDD)

rising 34.1 35.1 36.0

TPS2377 Voltage at VDD V

(VDD)

falling 29.7 30.5 31.4 V
Hysteresis 4.3 4.5 4.8

TPS2376 Input leakage, UVLO V

(UVLO)

= 0 V to 5 V -1 1 µA

THERMAL SHUTDOWN

Shutdown temperature Temperature rising 135 ° C
Hysteresis 20 ° C

BIAS CURRENT

Operating current I

(VDD)

240 450 µA

4

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DEVICE INFORMATION

−

+

10 V

Regulator

Thermal Shutdown,

Counter, and Latch

QS

R

−

+

−

+

3

2

12 V

22 V

1.5 V

& 10 V

2.5 V

−

+

VDD

RTN

45 mV

CLASS

DET

Current

Limit Amp.

UVLO

Comp.

EN

Delay

QS

R

5

8

6

PG

−
+

0 = Inrush

0 = Fault

1 = Limiting

PG Comparator

Detection

Comparator

Classification

Comparator

0

1

7

UVLO

’76 Only

−

+

2.5 V

1

ILIM

1:1

4

VSS

See

Note

Note: For The TPS2376, The UVLO Comparator

Connects To The UVLO Pin And Not The UVLO

Divider.

Current

Mirror

1 kOhms

0.08
Ohms

150 uS

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

FUNCTIONAL BLOCK DIAGRAM

5

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Detailed Pin Description

I

(LIM)



25000

R

(ILIM)

(1)

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

DEVICE INFORMATION (continued)

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.

ILIM 1 1 O The equation for calculating the resistor is shown in the detailed pin

description section for ILIM.
Connect a resistor from CLASS to VSS to set the classification of the

CLASS 2 2 O powered device (PD). The IEEE classification levels and corresponding

resistor values are shown in Table 1 .
Connect a 24.9-k Ω detection resistor from DET to VDD for a valid PD

DET 3 3 O

detection.

VSS 4 4 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

RTN 5 5 O

TPS2375 load.

PG 6 6 O Open-drain, power-good output; active high.

Used only on the TPS2376. Connect a resistor divider from VDD to VSS to

UVLO - 7 I

implement the adjustable UVLO feature of the TPS2376.
NC 7 - No connection
VDD 8 8 I Positive line from the rectified PSE provided input.

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 :

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 k Ω to 500 k Ω . A value of 178 k Ω is

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) R

(CLASS)

( Ω ) 802.3af LIMITS (mA) NOTE

0 0.44 – 12.95 4420 ± 1% 0 - 4 Default class
1 0.44 – 3.84 953 ± 1% 9 - 12
2 3.84 – 6.49 549 ± 1% 17 - 20
3 6.49 – 12.95 357 ± 1% 26 - 30
4 - 255 ± 1% 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 Ω , ± 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.

6

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TYPICAL CHARACTERISTICS

11.0

11.1

11.2

11.3

−40 −20 0 20 40 60 80 100 120

Classification Turnon Voltage − V

TA − Free-Air Temperature − °C

0

1

2

3

4

5

6

0 1 2 3 4 5 6 7 8 9 10 11

TA = 125°C

TA = 25°C

TA = −40°C

V

(VDD)

− V

Current − Aµ

10

15

20

25

30

35

1 3 5 7 9 11

Specification Limits

V

(PI)

− V

Resistance − kΩ

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

VSS: This is the input supply negative rail that serves as a local ground to the TPS2375.
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.

Graphs over temperature are interpolations between the marked data points.

I

(VDD)

+ I

(RTN)

IN DETECTION PD DETECTION RESISTANCE CLASSIFICATION TURNON

vs VOLTAGE

V

(PI)

vs

TEMPERATURE

Figure 2. Figure 3. Figure 4.

7

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21.90

21.91

21.92

21.93

21.94

−40 −20 0 20 40 60 80 100 120

Classification Turnoff Voltage − V

TA − Free-Air Temperature − °C

0.100

0.150

0.200

0.250

0.300

0.350

22 27 32 37 42 47 52 57

VDD − V

I

(VDD)

− mA

TA = 125°C

TA = 25°C

TA = −40°C

0.4

0.5

0.6

0.7

0.8

0.9

−40 −20 0 20 40 60 80 100 120

Pass Device Resistance − Ω

TA − Free-Air Temperature − °C

39.2

39.3

39.4

39.5

−40 −20 0 20 40 60 80 100 120

T

A

− Free-Air Temperature − °C

VDD − V

2.484

2.485

2.486

2.487

2.488

2.489

−40 −20 0 20 40 60 80 100 120

(UVLO)

TA − Free-Air Temperature − °C

V − V

30.40

30.44

30.48

30.52

30.56

30.60

−40 −20 0 20 40 60 80 100 120

T

A

− Free-Air Temperature − °C

VDD − V

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

TYPICAL CHARACTERISTICS (continued)

Graphs over temperature are interpolations between the marked data points.

CLASSIFICATION TURNOFF I

(VDD)

CURRENT PASS DEVICE

VOLTAGE vs RESISTANCE

vs VDD vs

TEMPERATURE TEMPERATURE

Figure 5. Figure 6. Figure 7.

TPS2375 TPS2375 TPS2376

UVLO RISING UVLO FALLING UVLO RISING

vs vs vs

TEMPERATURE TEMPERATURE TEMPERATURE

Figure 8. Figure 9. Figure 10.

8

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30.45

30.50

30.55

30.60

30.65

−40 −20 0 20 40 60 80 100 120

T

A

− Free-Air Temperature − °C

VDD − V

34.95

35.00

35.05

35.10

35.15

35.20

−40 −20 0 20 40 60 80 100 120

T

A

− Free-Air Temperature − °C

VDD − V

1.923

1.924

1.925

1.926

1.927

1.928

1.929

−40 −20 0 20 40 60 80 100 120

T

A

− Free-Air Temperature − °C

(UVLO)

V − V

425

430

435

440

−40 −20 0 20 40 60 80 100 120

T

A

− Free-Air Temperature − °C

I

(RTN)

− mA

90.5

91.0

91.5

92.0

92.5

93.0

93.5

94.0

−40 −20 0 20 40 60 80 100 120

Percent of Inrush Limit Current

TA − Free-Air Temperature − °C

100

125

150

175

200

225

250

275

300

325

350

−40 −20 0 20 40 60 80 100 120

I

(ILIM)

− mA

TA − Free-Air Temperature − °C

75 kΩ

125 kΩ

178 kΩ

120

140

160

180

−40 −20 0 20 40 60 80 100 120

PG Deglitch Period −

sµ

TA − Free-Air Temperature − °C

TPS2375
TPS2376
TPS2377

SLVS525A – APRIL 2004 – REVISED SEPTEMBER 2004

TYPICAL CHARACTERISTICS (continued)

Graphs over temperature are interpolations between the marked data points.

TPS2376 TPS2377 TPS2377

UVLO FALLING UVLO RISING UVLO FALLING

vs vs vs

TEMPERATURE TEMPERATURE TEMPERATURE

Figure 11. Figure 12. Figure 13.

INRUSH STATE TERMINATION INRUSH CURRENT CURRENT LIMIT

THRESHOLD vs vs

vs TEMPERATURE TEMPERATURE

TEMPERATURE

Figure 14. Figure 15. Figure 16.

PG DEGLITCH PERIOD

vs

TEMPERATURE

Figure 17.

9