TI TPS2049DG4

TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
SINGLE-CHANNEL 100 mA POWER SWITCH
FEATURES
•
•
•
•
•
•
•
•
•
100-mA Continuous Current
600-mΩ High-Side MOSFET
Thermal and Short-Circuit Protection
Operating Range: 2.7 V to 5.5 V
0.6-ms Typical Rise Time
Undervoltage Lockout
Deglitched Fault Report (OC)
43 µA Quiescent Supply Current
1-µA Maximum Standby Supply Current
•
•
•
SOIC-8 Package
Ambient Temperature Range: –40°C to 85°C
2 µS Response Time to Short Circuit
GND
IN
IN
EN
OUT
OUT
OUT
OC
DESCRIPTION
The TPS2049 power-distribution switch is intended for applications where heavy capacitive loads and short
circuits are likely to be encountered. This device incorporates a 600-mΩ N-channel MOSFET power switch for
power-distribution systems that require only one power distribution path. The switch is controlled by a logic
enable input. Gate drive is provided by an internal charge pump designed to control the power-switch rise times
and fall times to minimize current surges during switching. The charge pump requires no external components
and allows operation from supplies as low as 2.7V.
When the output load exceeds the current-limit threshold or a short is present, the device limits the output
current to a safe level by switching into a constant-current mode, pulling the overcurrent (OC) logic output low.
When continuous heavy overloads and short circuits increase the power dissipation in the switch, causing the
junction temperature to rise, a thermal protection circuit shuts off the switch to prevent damage. Recovery from a
thermal shutdown is automatic once the device has cooled sufficiently. Internal circuitry ensures the switch
remains off until valid input voltage is present. This power-distribution switch is designed to set current limit at
150mA typically.
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 © 2006, Texas Instruments Incorporated
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
AVAILABLE OPTION AND ORDERING INFORMATION (1)
TA
ENABLE
RECOMMENDED MAXIMUM
CONTINUOUS LOAD CURRENT
(mA)
TYPICAL SHORT-CIRCUIT
CURRENT LIMIT AT 25°C
(mA)
NUMBER OF
SWITCHES
SOIC (D)
–40°C to 85°C
Active low
100
150
Single
TPS2049D (2)
(1)
(2)
For the most current package and ordering nformation, see the Package Option Addendum at the end of this document, or see the TI
website at www.ti.com.
The package is available taped and reeled. Add an R suffix to device types (e.g., TPS2042BDR)
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range unless otherwise noted (1)
VALUE
UNIT
–0.3 to 6
V
-0.3 to 6
V
Input voltage range
–0.3 to 6
V
Voltage range
–0.3 to 6
V
(2)
VI(IN)
Input voltage range
VO(OUT)
Output voltage range
VI(EN)
VI(OC)
IO(OUT)
Continuous output current
(2)
Internally limited
Continuous total power dissipation
See Dissipation Rating Table
TJ
Operating virtual junction temperature range
–40 to 125
°C
Tstg
Storage temperature range
–65 to 150
°C
Lead temperature soldering 1,6 mm (1/16 inch) from case for 10 seconds
Electrostatic discharge (ESD)
protection
(1)
(2)
Human body model MIL-STD-883C
Charge device model (CDM)
260
°C
2
kV
500
V
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.
All voltages are with respect to GND.
DISSIPATING RATING TABLE
PACKAGE
TA≤ 25°C
POWER RATING
DERATING FACTOR
ABOVE TA = 25°C
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
D-8
585.82 mW
5.8582 mW/°C
322.20 mW
234.32 mW
RECOMMENDED OPERATING CONDITIONS
2
MIN
MAX
VI(IN)
Input voltage
2.7
5.5
V
VI(EN)
Input voltage
0
5.5
V
IO(OUT)
Continuous output current
0
100
mA
TJ
Operating virtual junction temperature
–40
125
°C
Submit Documentation Feedback
UNIT
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
ELECTRICAL CHARACTERISTICS
over recommended operating junction temperature range, VI(IN) = 5.5 V, IO = 90 mA, VI(EN) = 0 V (unless otherwise noted)
TEST CONDITIONS (1)
PARAMETER
MIN
TYP MAX
UNIT
POWER SWITCH
rDS(on)
Static drain-source
on-state resistance, 5-V
operation and 2.7-V
operation
VI(IN) = 2.7 V or 5.5 V,
IO = 90 A,
–40°C < TJ < 125°C
400
650
mΩ
tr
Rise time, output
VI(IN) = 2.7 V
CL = 1 µF,
RL = 50 Ω, TJ = 25°C
0.1
0.4
ms
tf
Fall time, output
VI(IN) = 2.7 V
CL = 1 µF,
RL = 50 Ω, TJ = 25°C
0.3
ms
0.03
ENABLE INPUT EN
VIH
High-level input voltage
2.7 V ≤ VI(IN)≤ 5.5 V
VIL
Low-level input voltage
2.7 V ≤ VI(IN)≤ 5.5 V
II
Input current
VI(EN) = 0 V or VI(EN) = VI(IN)
ton
Turnon time
toff
Turnoff time
2
V
0.8
V
0.5
µA
CL = 1 µF, RL = 50 Ω, TJ = 25°C
1
ms
CL = 1 µF, RL = 50 Ω, TJ = 25°C
1
ms
200
mA
325
mA
–0.5
CURRENT LIMIT
IOS
Short-circuit output
current
VI(IN) = 5 V, OUT connected to GND, Device enabled into
short-circuit, 10°C < TJ < 40°C
IOC_trip
Overcurrent trip threshold
10°C < TJ < 40°C, 100 A/sec current rate increase
100
Short-circuit response
tme
150
µs
2
SUPPLY CURRENT
TJ = 25°C
0.5
1
–40°C ≤ TJ ≤ 125°C
0.5
5
TJ = 25°C
43
60
–40°C ≤ TJ ≤ 125°C
43
70
VI(EN) = 5.5 V,
–40°C ≤ TJ≤ 125°C
1
µA
VI(OUT) = 5.5 V,
VI(EN) = 0 V
TJ = 25°C
0
µA
Supply current, low-level output
No load on OUT
VI(EN) = 5.5 V
Supply current, high-level output
No load on OUT
VI(EN) = 0 V
Leakage current
OUT connected to
ground
Reverse leakage current
IN = ground
µA
µA
UNDERVOLTAGE LOCKOUT
IN
Low-level input voltage
IN
Hysteresis
2
TJ = 25°C
2.5
75
V
mV
OVERCURRENT OC
VOL(OC)
Output low voltage
IO(OC) = 5 mA
0.4
Off-state current
VO(OC) = 5 V or 3.3 V
OC deglitch
OC assertion or deassertion
4
8
V
1
µA
15
ms
THERMAL SHUTDOWN (2)
Thermal shutdown threshold
135
Recovery from thermal shutdown
125
Hysteresis
(1)
(2)
°C
°C
10
°C
Pulse-testing techniques maintain junction temperature close to ambient temperature; thermal effects must be taken into account
separately.
The thermal shutdown only reacts under overcurrent conditions.
Submit Documentation Feedback
3
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
FUNCTIONAL BLOCK DIAGRAM
TERMINAL FUNCTIONS
TERMINAL
NAME
I/O
DESCRIPTION
EN1
4
I
Enable input, logic low turns on power switch
GND
1
I
Ground
IN
2, 3
I
Input voltage
OC
5
O
Overcurrent, report, active-low, open-drain output
6, 7, 8
O
Power-switch output
OUT
4
NO.
Submit Documentation Feedback
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
PARAMETER MEASUREMENT INFORMATION
OUT
RL
tf
tr
CL
VO(OUT)
90%
10%
90%
10%
TEST CIRCUIT
50%
VI(EN)
50%
toff
ton
VO(OUT)
50%
VI(EN)
90%
50%
toff
ton
VO(OUT)
10%
90%
10%
VOLTAGE WAVEFORMS
Figure 1. Test Circuit and Voltage Waveforms
RL = 50 W
VI(EN)
2 V/div
CL = 1 m F
VO(OUT)
2 V/div
VI(EN)
2 V/div
RL = 50 W
CL = 1 m F
VO(OUT1)
2 V/div
t - Time - 100 ms/div
t - Time - 100 ms/div
Figure 2. Turnon Delay and Rise Time With 1-µF Load
Figure 3. Turnoff Delay and Fall Time With 1-µF Load
Submit Documentation Feedback
5
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
PARAMETER MEASUREMENT INFORMATION (continued)
VI(EN)
5 V/div
Enable Into a Short
Watching OC Flag’s Delay
VO(OUT1)
5 V/div
Hotshort 5 Ω on Output
Watch Current Limit
Response Time.
OC
200 ms/div
IO(OUT1)
200 mA/div
VI(OUT)
5 V/div
t - Time - 2 ms/div
t - Time - 2 ms/div
Figure 4. Device Enabled Into a Short
6
Figure 5. 5-Ω Load Connected to Enabled Device
Submit Documentation Feedback
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
APPLICATION INFORMATION
2,3
6,7,8
5
4
Figure 6. Typical Application
POWER-SUPPLY CONSIDERATIONS
A 0.01-µF to 0.1-µF ceramic bypass capacitor between IN and GND, close to the device, is recommended.
Placing a high-value electrolytic capacitor on the output pin(s) is recommended when the output load is heavy.
This precaution reduces power-supply transients that may cause ringing on the input. Additionally, bypassing the
output with a 0.01-µF to 0.1-µF ceramic capacitor improves the immunity of the device to short-circuit transients.
OVERCURRENT
A sense FET is employed to check for overcurrent conditions. Unlike current–sense resistors, sense FETs do
not increase the series resistance of the current path. When an overcurrent condition is detected, the device
maintains a constant output current and reduces the output voltage accordingly. Complete shutdown occurs only
if the fault is present long enough to activate thermal limiting.
Three possible overload conditions can occur. In the first condition, the output has been shorted before the
device is enabled or before VI(IN) has been applied (see Figure 6). The TPS2049 senses the short and
immediately switches into a constant-current output.
In the second condition, a short or an overload occurs while the device is enabled. At the instant the overload
occurs, very high currents may flow for a short period of time before the current-limit circuit can react. After the
current-limit circuit has tripped (reached the overcurrent trip threshhold) the device switches into constant-current
mode.
In the third condition, the load has been gradually increased beyond the recommended operating current. The
current is permitted to rise until the current-limit threshold is reached or until the thermal limit of the device is
exceeded. The TPS2049 is capable of delivering current up to the current-limit threshold without damaging the
device. Once the threshold has been reached, the device switches into its constant-current mode.
OC RESPONSE
The OC open-drain output is asserted (active low) when an overcurrent or overtemperature shutdown condition
is encountered after a 10-ms deglitch timeout. The output remains asserted until the overcurrent or
overtemperature condition is removed. Connecting a heavy capacitive load to an enabled device can cause a
momentary overcurrent condition; however, no false reporting on OC occurs due to the 10-ms deglitch circuit.
The TPS2049 is designed to eliminate false overcurrent reporting. The internal overcurrent deglitch eliminates
the need for external components to remove unwanted pulses. OC is not deglitched when the switch is turned
off due to an overtemperature shutdown.
Figure 7. Typical Circuit for the OC Pin
Submit Documentation Feedback
7
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
APPLICATION INFORMATION (continued)
POWER DISSIPATION AND JUNCTION TEMPERATURE
The low on-resistance on the n-channel MOSFET allows small surface-mount packages to pass large currents.
The thermal resistances of these packages are high compared to those of power packages; it is good design
practice to check power dissipation and junction temperature. Begin by determining the rDS(on) of the N-channel
MOSFET relative to the input voltage and operating temperature. As an initial estimate, use the highest
operating ambient temperature of interest. Using this value, the power dissipation per switch can be calculated
by:
PD = rDS(on)× I2
Finally, calculate the junction temperature:
TJ = PD× RΘJA + TA
Where:
TA = Ambient temperature °C
RΘJA = Thermal resistance
PD = Total power dissipation based on number of switches being used.
Compare the calculated junction temperature with the initial estimate. If they do not agree within a few degrees,
repeat the calculation, using the calculated value as the new estimate. Two or three iterations are generally
sufficient to get a reasonable answer.
THERMAL PROTECTION
Thermal protection prevents damage to the IC when heavy-overload or short-circuit faults are present for
extended periods of time. The TPS2049 implement a thermal sensing to monitor the operating junction
temperature of the power distribution switch. In an overcurrent or short-circuit condition the junction temperature
will rise due to excessive power dissipation. Once the die temperature rises to approximately 140°C due to
overcurrent conditions, the internal thermal sense circuitry turns the power switch off, thus preventing the power
switch from damage. Hysteresis is built into the thermal sense circuit, and after the device has cooled
approximately 10°C, the switch turns back on. The switch continues to cycle in this manner until the load fault or
input power is removed. The OC open-drain output is asserted (active low) when an overtemperature shutdown
or overcurrent occurs.
UNDERVOLTAGE LOCKOUT (UVLO)
An undervoltage lockout ensures that the power switch is in the off state at power up. Whenever the input
voltage falls below approximately 2 V, the power switch will be quickly turned off. This facilitates the design of
hot-insertion systems where it is not possible to turn off the power switch before input power is removed. The
UVLO will also keep the switch from being turned on until the power supply has reached at least 2 V, even if the
switch is enabled. Upon reinsertion, the power switch will be turned on, with a controlled rise time to reduce EMI
and voltage overshoots.
8
Submit Documentation Feedback
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
APPLICATION INFORMATION (continued)
GENERIC HOT-PLUG APPLICATIONS (see Figure 8)
In many applications it may be necessary to remove modules or pc boards while the main unit is still operating.
These are considered hot-plug applications. Such implementations require the control of current surges seen by
the main power supply and the card being inserted. The most effective way to control these surges is to limit and
slowly ramp the current and voltage being applied to the card, similar to the way in which a power supply
normally turns on. Due to the controlled rise times and fall times of the TPS2049, these devices can be used to
provide a softer start-up to devices being hot-plugged into a powered system. The UVLO feature of the
TPS2049 also ensures the switch will be off after the card has been removed, and the switch will be off during
the next insertion. The UVLO feature insures a soft start with a controlled rise time for every insertion of the card
or module.
Figure 8. Typical Hot-Plug Implementation
By placing the TPS2049 between the VCC input and the rest of the circuitry, the input power reaches these
devices first after insertion. The typical rise time of the switch is approximately 1 ms, providing a slow voltage
ramp at the output of the device. This implementation controls system surge currents and provides a
hot-plugging mechanism for any device.
DETAILED DESCRIPTION
POWER SWITCH
The power switch is an N-channel MOSFET with a low on-state resistance. Configured as a high-side switch,
the power switch prevents current flow from OUT to IN and IN to OUT when disabled. The power switch
supplies a minimum current of 90 mA.
CHARGE PUMP
An internal charge pump supplies power to the driver circuit and provides the necessary voltage to pull the gate
of the MOSFET above the source. The charge pump operates from input voltages as low as 2.7 V and requires
little supply current.
DRIVER
The driver controls the gate voltage of the power switch. To limit large current surges and reduce the associated
electromagnetic interference (EMI) produced, the driver incorporates circuitry that controls the rise times and fall
times of the output voltage.
ENABLE (EN)
The logic enable pin disables the power switch and the bias for the charge pump, driver, and other circuitry to
reduce the supply current. The supply current is reduced to less than 1 µA when a logic high is present on EN. A
logic zero input on EN restores bias to the drive and control circuits and turns the switch on. The enable input is
compatible with both TTL and CMOS logic levels.
Submit Documentation Feedback
9
TPS2049
www.ti.com
SLVS713 – OCTOBER 2006
DETAILED DESCRIPTION (continued)
OVERCURRENT (OC)
The OC open-drain output is asserted (active low) when an overcurrent or overtemperature condition is
encountered. The output remains asserted until the overcurrent or overtemperature condition is removed. A
10-ms deglitch circuit prevents the OC signal from oscillation or false triggering. If an overtemperature shutdown
occurs, the OC is asserted instantaneously.
CURRENT SENSE
A sense FET monitors the current supplied to the load. The sense FET measures current more efficiently than
conventional resistance methods. When an overload or short circuit is encountered, the current-sense circuitry
sends a control signal to the driver. The driver in turn reduces the gate voltage and drives the power FET into its
saturation region, which switches the output into a constant-current mode and holds the current constant while
varying the voltage on the load.
THERMAL SENSE
The TPS2049 implements a thermal sensing to monitor the operating temperature of the power distribution
switch. In an overcurrent or short-circuit condition, the junction temperature rises. When the die temperature
rises to approximately 140°C due to overcurrent conditions, the internal thermal sense circuitry turns off the
switch, thus preventing the device from damage. Hysteresis is built into the thermal sense, and after the device
has cooled approximately 10 degrees, the switch turns back on. The switch continues to cycle off and on until
the fault is removed. The open-drain false reporting output (OC) is asserted (active low) when an
overtemperature shutdown or overcurrent occurs.
UNDERVOLTAGE LOCKOUT
A voltage sense circuit monitors the input voltage. When the input voltage is below approximately 2V, a control
signal turns off the power switch.
10
Submit Documentation Feedback
PACKAGE OPTION ADDENDUM
www.ti.com
6-Nov-2006
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TPS2049D
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPS2049DG4
ACTIVE
SOIC
D
8
75
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPS2049DR
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
TPS2049DRG4
ACTIVE
SOIC
D
8
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
Lead/Ball Finish
MSL Peak Temp (3)
(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.
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 1
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications,
enhancements, improvements, and other changes to its products and services at any time and to discontinue
any product or service without notice. Customers should obtain the latest relevant information before placing
orders and should verify that such information is current and complete. All products are sold subject to TI’s terms
and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI
deems necessary to support this warranty. Except where mandated by government requirements, testing of all
parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for
their products and applications using TI components. To minimize the risks associated with customer products
and applications, customers should provide adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right,
copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process
in which TI products or services are used. Information published by TI regarding third-party products or services
does not constitute a license from TI to use such products or services or a warranty or endorsement thereof.
Use of such information may require a license from a third party under the patents or other intellectual property
of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without
alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction
of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for
such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that
product or service voids all express and any implied warranties for the associated TI product or service and
is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Following are URLs where you can obtain information on other Texas Instruments products and application
solutions:
Products
Applications
Amplifiers
amplifier.ti.com
Audio
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DSP
dsp.ti.com
Broadband
www.ti.com/broadband
Interface
interface.ti.com
Digital Control
www.ti.com/digitalcontrol
Logic
logic.ti.com
Military
www.ti.com/military
Power Mgmt
power.ti.com
Optical Networking
www.ti.com/opticalnetwork
Microcontrollers
microcontroller.ti.com
Security
www.ti.com/security
Low Power Wireless www.ti.com/lpw
Mailing Address:
Telephony
www.ti.com/telephony
Video & Imaging
www.ti.com/video
Wireless
www.ti.com/wireless
Texas Instruments
Post Office Box 655303 Dallas, Texas 75265
Copyright  2006, Texas Instruments Incorporated