Filters
  • Manufacturer
    • Texas Instruments
    • Rochester Electronics
    • ON Semiconductor
    • NXP
    • Fairchild
    • Nexperia
    • Renesas
    • IDT
    • National Semiconductor
    • Diodes
    • Analog Devices, Inc.
    • Cypress
    • HARRIS
    • STMicroelectronics
    • Intersil
    • Wuxi I-core Elec
  • Base Part Number
  • Logic Type
  • Moisture Sensitivity Level (MSL)
  • Mounting Type
  • Number of Circuits
  • Operating Temperature
  • Package / Case
  • Packaging
  • Part Status
  • RoHS Status
  • Mount
  • Number of Pins

Attribute column

Categories

Logic - Universal Bus Functions

View Mode:
877 Results

Product

Inventory

Pricing(USD)

Quantity

Datasheet

RoHS

Factory Lead Time

Lifecycle Status

Contact Plating

Mount

Mounting Type

Package / Case

Number of Pins

Weight

Number of Elements

Operating Temperature

Packaging

Series

JESD-609 Code

Pbfree Code

Part Status

Moisture Sensitivity Level (MSL)

Number of Terminations

ECCN Code

Terminal Finish

Additional Feature

Packing Method

Voltage - Supply

Terminal Position

Terminal Form

Peak Reflow Temperature (Cel)

Number of Functions

Supply Voltage

Terminal Pitch

Frequency

Time@Peak Reflow Temperature-Max (s)

Base Part Number

Pin Count

Number of Outputs

Qualification Status

Output Voltage

Operating Supply Voltage

Polarity

Supply Voltage-Max (Vsup)

Power Supplies

Supply Voltage-Min (Vsup)

Number of Channels

Number of Circuits

Operating Supply Current

Load Capacitance

Number of Ports

Nominal Supply Current

Output Current

Max Supply Current

uPs/uCs/Peripheral ICs Type

Number of Bits

Propagation Delay

Quiescent Current

Turn On Delay Time

Family

Logic Function

Direction

Output Characteristics

Logic Type

Nominal Input Voltage

Output Polarity

Max I(ol)

Prop. Delay@Nom-Sup

Trigger Type

Control Type

Schmitt Trigger

Power Supply Current-Max (ICC)

Number of Input Lines

Input Current

Count Direction

Translation

Height

Length

Width

Thickness

Radiation Hardening

REACH SVHC

RoHS Status

Lead Free

SN74ALVCH16601DGGR
SN74ALVCH16601DGGR

Texas Instruments

216

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 4 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

252.792698mg

1

-40°C~85°C

Cut Tape (CT)

74ALVCH

e4

yes

Active

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

WITH INDEPENDENT OUTPUT ENABLE FOR EACH DIRECTION; WITH CLOCK ENABLE

TR

1.65V~3.6V

DUAL

GULL WING

260

1

1.8V

0.5mm

-

-

74ALVCH16601

56

-

-

-

-

Non-Inverting

3.6V

3.3V

-

-

18-Bit

-

50pF

2

-

-

40μA

-

18

5.8 ns

-

6.1 ns

ALVC/VCX/A

Transceiver

Bidirectional

3-STATE

Universal Bus Transceiver

-

-

0.024 A

-

POSITIVE EDGE

INDEPENDENT CONTROL

-

0.04mA

-

-

-

N/A

1.2mm

14mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

SN74VMEH22501ADGGR
SN74VMEH22501ADGGR

Texas Instruments

822

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 5 days ago)

-

Surface Mount

Surface Mount

48-TFSOP (0.240, 6.10mm Width)

48

223.195796mg

1

-40°C~85°C

Tape & Reel (TR)

74VMEH

e4

yes

Active

1 (Unlimited)

48

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

3.15V~3.45V

-

GULL WING

260

1

3.3V

0.5mm

-

-

74VMEH22501

48

-

-

-

3.3V

Non-Inverting

3.45V

-

-

-

8-Bit and Dual 1-Bit

-

-

2

-

64mA

-

-

10

10.1 ns

-

14.5 ns

74V

Transceiver

Bidirectional

3-STATE WITH SERIES RESISTOR

Universal Bus Transceiver

-

-

-

-

POSITIVE EDGE

COMMON CONTROL

-

30mA

-

-

-

N/A

1.2mm

12.5mm

6.1mm

1.15mm

No

No SVHC

ROHS3 Compliant

Lead Free

SN74VMEH22501ADGVR
SN74VMEH22501ADGVR

Texas Instruments

496

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 5 days ago)

-

Surface Mount

Surface Mount

48-TFSOP (0.173, 4.40mm Width)

48

123.490523mg

1

-40°C~85°C

Tape & Reel (TR)

74VMEH

e4

yes

Active

1 (Unlimited)

48

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

3.15V~3.45V

-

GULL WING

260

1

3.3V

0.4mm

-

-

74VMEH22501

48

-

-

-

3.3V

Non-Inverting

3.45V

-

-

-

8-Bit and Dual 1-Bit

-

-

2

-

64mA

30mA

-

10

10.1 ns

-

14.5 ns

74V

Transceiver

Bidirectional

3-STATE WITH SERIES RESISTOR

Universal Bus Transceiver

-

-

-

-

POSITIVE EDGE

COMMON CONTROL

-

-

-

-

-

N/A

1.2mm

9.7mm

4.4mm

1.05mm

No

No SVHC

ROHS3 Compliant

Lead Free

SN74VMEH22501DGGR
SN74VMEH22501DGGR

Texas Instruments

1000

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 5 days ago)

Gold

Surface Mount

Surface Mount

48-TFSOP (0.240, 6.10mm Width)

48

223.195796mg

1

-40°C~85°C

Cut Tape (CT)

74VMEH

e4

yes

Active

1 (Unlimited)

48

EAR99

-

-

TR

3.15V~3.45V

-

GULL WING

260

1

3.3V

0.5mm

-

-

74VMEH22501

48

-

-

2.4V

3.3V

Non-Inverting

3.45V

-

-

8

8-Bit and Dual 1-Bit

-

-

2

-

64mA

30mA

-

10

14.5 ns

30mA

14.5 ns

74V

Transceiver

Bidirectional

3-STATE WITH SERIES RESISTOR

Universal Bus Transceiver

2V

-

-

-

POSITIVE EDGE

COMMON CONTROL

-

-

-

-

-

N/A

1.2mm

12.5mm

6.1mm

1.15mm

No

No SVHC

ROHS3 Compliant

Lead Free

SN74VMEH22501DGVR
SN74VMEH22501DGVR

Texas Instruments

2000

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 5 days ago)

-

Surface Mount

Surface Mount

48-TFSOP (0.173, 4.40mm Width)

48

123.490523mg

1

-40°C~85°C

Cut Tape (CT)

74VMEH

e4

yes

Active

1 (Unlimited)

48

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

3.15V~3.45V

-

GULL WING

260

1

3.3V

0.4mm

-

-

74VMEH22501

48

-

-

-

3.3V

Non-Inverting

3.45V

-

-

-

8-Bit and Dual 1-Bit

-

-

2

-

64mA

30mA

-

10

14.5 ns

-

14.5 ns

74V

Transceiver

Bidirectional

3-STATE WITH SERIES RESISTOR

Universal Bus Transceiver

-

-

-

-

POSITIVE EDGE

COMMON CONTROL

-

-

-

-

-

N/A

1.2mm

9.7mm

4.4mm

1.05mm

No

-

ROHS3 Compliant

Lead Free

SN74ALVCH16501DGGR
SN74ALVCH16501DGGR

Texas Instruments

970

-

Datasheet

-

ACTIVE (Last Updated: 4 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

252.792698mg

1

-40°C~85°C

Cut Tape (CT)

74ALVCH

e4

yes

Discontinued

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

WITH INDEPENDENT OUTPUT ENABLE FOR EACH DIRECTION

TR

1.65V~3.6V

DUAL

GULL WING

260

1

2.5V

0.5mm

-

-

74ALVCH16501

56

-

-

-

-

Non-Inverting

3.6V

3.3V

-

-

18-Bit

-

50pF

2

-

-

40μA

-

18

6.3 ns

-

6.3 ns

ALVC/VCX/A

Transceiver

Bidirectional

3-STATE

Universal Bus Transceiver

-

-

0.024 A

3.9 ns

POSITIVE EDGE

INDEPENDENT CONTROL

-

0.04mA

-

-

-

N/A

1.2mm

14mm

6.1mm

1.15mm

No

No SVHC

ROHS3 Compliant

Lead Free

SN74GTL1655DGGR
SN74GTL1655DGGR

Texas Instruments

969

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 4 days ago)

-

Surface Mount

Surface Mount

64-TFSOP (0.240, 6.10mm Width)

64

262.601633mg

1

-40°C~85°C

Cut Tape (CT)

74GTL

e4

yes

Active

1 (Unlimited)

64

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

3V~3.6V

DUAL

GULL WING

260

2

3.3V

0.5mm

160MHz

-

74GTL1655

64

-

-

-

3.3V

Non-Inverting

3.6V

-

3V

-

16-Bit

-

-

2

5mA

100mA

-

-

16

6.7 ns

-

6.7 ns

GTL/TVC

Transceiver

Bidirectional

3-STATE

Universal Bus Transceiver

-

-

0.024 A

6.5 ns

POSITIVE EDGE

INDEPENDENT CONTROL

-

80mA

-

-

-

GTL/P & LVTTL

1.2mm

17mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

SN74ABT16501DLR
SN74ABT16501DLR

Texas Instruments

1000

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 4 days ago)

-

Surface Mount

Surface Mount

56-BSSOP (0.295, 7.50mm Width)

56

689.999043mg

1

-40°C~85°C

Cut Tape (CT)

74ABT

e4

yes

Active

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

WITH INDEPENDENT OUTPUT ENABLE FOR EACH DIRECTION

TR

4.5V~5.5V

DUAL

GULL WING

260

1

5V

0.635mm

-

-

74ABT16501

56

-

-

-

5V

Non-Inverting

-

5V

-

-

18-Bit

-

50pF

2

-

-

76mA

-

18

6.5 ns

-

6.5 ns

ABT

AND, D-Type, Transceiver

Bidirectional

3-STATE

Universal Bus Transceiver

-

-

0.064 A

4 ns

POSITIVE EDGE

INDEPENDENT CONTROL

-

-

-

-

-

N/A

2.79mm

18.41mm

7.49mm

2.59mm

No

-

ROHS3 Compliant

Lead Free

SN74ABTH18502APM
SN74ABTH18502APM

Texas Instruments

96

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 1 day ago)

Gold

Surface Mount

Surface Mount

64-LQFP

64

342.689036mg

2

-40°C~85°C

Tray

74ABTH

e4

yes

Active

3 (168 Hours)

64

EAR99

-

WITH INDEPENDENT OUTPUT ENABLE FOR EACH DIRECTION

-

4.5V~5.5V

QUAD

GULL WING

260

2

5V

0.5mm

-

-

74ABTH18502

64

-

-

-

5V

Non-Inverting

-

5V

-

-

18-Bit

-

50pF

2

-

-

-

-

18

5 ns

19mA

15 ns

ABT

Transceiver

Bidirectional

3-STATE

Scan Test Universal Bus Transceiver

-

-

-

-

POSITIVE EDGE

INDEPENDENT CONTROL

-

-

-

-

-

N/A

1.6mm

10mm

10mm

1.4mm

No

-

ROHS3 Compliant

Lead Free

SN74ALVC162836DGGR
SN74ALVC162836DGGR

Texas Instruments

993

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 4 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

249.986095mg

1

-40°C~85°C

Cut Tape (CT)

74ALVC

e4

yes

Active

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

1.65V~3.6V

DUAL

GULL WING

260

1

1.8V

0.5mm

-

-

74ALVC162836

56

-

-

-

-

Non-Inverting

3.6V

3.3V

-

20

20-Bit

-

50pF

2

128mA

12mA

-

-

20

6.5 ns

-

6.5 ns

ALVC/VCX/A

-

Unidirectional

3-STATE WITH SERIES RESISTOR

Universal Bus Driver

-

-

-

4 ns

-

ENABLE LOW

-

0.04mA

-

-

-

N/A

1.2mm

14mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

SN74ALVCH162836GR
SN74ALVCH162836GR

Texas Instruments

10000

-

Datasheet

-

ACTIVE (Last Updated: 2 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

249.986095mg

1

-40°C~85°C

Cut Tape (CT)

74ALVCH

e4

yes

Discontinued

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

1.65V~3.6V

DUAL

GULL WING

260

1

1.8V

0.5mm

-

NOT SPECIFIED

74ALVCH162836

56

-

Not Qualified

-

-

Non-Inverting

3.6V

3.3V

-

20

20-Bit

-

50pF

2

-

12mA

-

-

20

5.5 ns

-

6.5 ns

ALVC/VCX/A

-

Unidirectional

3-STATE WITH SERIES RESISTOR

Universal Bus Driver

-

-

-

4 ns

-

ENABLE LOW

-

0.04mA

-

-

-

N/A

1.2mm

14mm

6.1mm

1.15mm

-

-

ROHS3 Compliant

Lead Free

SN74ALVC16334DGGR
SN74ALVC16334DGGR

Texas Instruments

99000

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 4 days ago)

-

Surface Mount

Surface Mount

48-TFSOP (0.240, 6.10mm Width)

48

223.195796mg

1

-40°C~85°C

Cut Tape (CT)

74ALVC

e4

yes

Active

1 (Unlimited)

48

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

1.65V~3.6V

DUAL

GULL WING

260

1

1.8V

0.5mm

-

-

74ALVC16334

48

-

-

-

3.3V

Non-Inverting

3.6V

-

-

16

16-Bit

-

50pF

2

-

24mA

40μA

-

16

4.5 ns

-

5.4 ns

ALVC/VCX/A

-

Unidirectional

3-STATE

Universal Bus Driver

2V

-

0.024 A

3.3 ns

-

ENABLE LOW

-

0.04mA

-

-

-

N/A

1.2mm

12.5mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

SN74ALVCF162835GR
SN74ALVCF162835GR

Texas Instruments

1359

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 5 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

249.986095mg

1

-40°C~85°C

Cut Tape (CT)

74ALVCF

e4

yes

Active

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

2.3V~3.6V

DUAL

GULL WING

260

1

2.5V

0.5mm

-

-

74ALVCF162835

56

-

-

-

-

Non-Inverting

3.6V

3.3V

2.3V

18

18-Bit

100nA

50pF

2

-

18mA

40μA

-

18

5.6 ns

100nA

6 ns

ALVC/VCX/A

-

Unidirectional

3-STATE

Universal Bus Driver

-

-

-

3.5 ns

-

ENABLE LOW

-

0.04mA

-

-

-

N/A

1.2mm

14mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

SN74GTLPH1655DGGR
SN74GTLPH1655DGGR

Texas Instruments

189

-

Datasheet

8 Weeks

ACTIVE (Last Updated: 4 days ago)

-

Surface Mount

Surface Mount

64-TFSOP (0.240, 6.10mm Width)

64

262.601633mg

1

-40°C~85°C

Cut Tape (CT)

74GTLPH

e4

yes

Active

1 (Unlimited)

64

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

3.15V~3.45V

DUAL

GULL WING

260

2

3.3V

0.5mm

-

-

74GTLPH1655

64

-

-

-

3.3V

Non-Inverting

3.45V

-

-

-

16-Bit

-

-

2

40mA

100mA

-

-

16

800 ps

-

7.8 ns

-

Transceiver

Bidirectional

3-STATE

Universal Bus Transceiver

-

-

0.024 A

7.7 ns

POSITIVE EDGE

INDEPENDENT CONTROL

-

-

-

-

-

GTL/P & LVTTL

1.2mm

17mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

CD74HC299M
CD74HC299M

Texas Instruments

13

-

-

6 Weeks

ACTIVE (Last Updated: 2 days ago)

Gold

Surface Mount

Surface Mount

20-SOIC (0.295, 7.50mm Width)

20

500.709277mg

1

-55°C~125°C

Tube

74HC

e4

yes

Active

1 (Unlimited)

20

EAR99

-

COMMON I/O PINS; GATED OUTPUT CONTROL

-

2V~6V

DUAL

GULL WING

260

1

4.5V

-

50MHz

-

74HC299

20

-

-

-

-

-

6V

2/6V

2V

-

8-Bit

-

50pF

-

-

-

-

-

8

300 ns

8μA

300 ns

HC/UH

Shift Register

Bidirectional

-

Universal Shift Register

-

TRUE

0.0052 A

-

POSITIVE EDGE

-

No

-

3

1μA

-

-

2.65mm

12.8mm

7.5mm

2.35mm

No

No SVHC

ROHS3 Compliant

Lead Free

SN74GTLPH16912GR
SN74GTLPH16912GR

Texas Instruments

77

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 5 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

252.792698mg

1

-40°C~85°C

Cut Tape (CT)

74GTLPH

e4

yes

Active

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

3.15V~3.45V

DUAL

GULL WING

260

1

3.3V

0.5mm

-

-

74GTLPH16912

56

-

-

-

3.3V

Non-Inverting

3.45V

-

-

-

18-Bit

-

-

2

50mA

50mA

-

-

18

6.5 ns

-

6.5 ns

-

Transceiver

Bidirectional

3-STATE

Universal Bus Transceiver

-

-

0.024 A

-

POSITIVE EDGE

INDEPENDENT CONTROL

-

-

-

-

-

GTL/P & LVTTL

1.2mm

14mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

CD74HC299M96
CD74HC299M96

Texas Instruments

20000
-

6 Weeks

ACTIVE (Last Updated: 1 day ago)

Gold

Surface Mount

Surface Mount

20-SOIC (0.295, 7.50mm Width)

20

500.709277mg

1

-55°C~125°C

Cut Tape (CT)

74HC

e4

yes

Active

1 (Unlimited)

20

EAR99

-

COMMON I/O PINS; GATED OUTPUT CONTROL

TR

2V~6V

DUAL

GULL WING

260

1

4.5V

-

-

-

74HC299

20

-

-

-

-

-

6V

2/6V

2V

-

8-Bit

-

50pF

-

-

-

-

-

8

300 ns

8μA

300 ns

HC/UH

Shift Register

Bidirectional

-

Universal Shift Register

-

TRUE

0.0052 A

-

POSITIVE EDGE

-

No

-

3

-

-

-

2.65mm

12.8mm

7.5mm

2.35mm

No

No SVHC

ROHS3 Compliant

Lead Free

SN74LVT18512DGGR
SN74LVT18512DGGR

Texas Instruments

1

-

Datasheet

6 Weeks

ACTIVE (Last Updated: 3 days ago)

Gold

Surface Mount

Surface Mount

64-TFSOP (0.240, 6.10mm Width)

64

262.601633mg

2

-40°C~85°C

Cut Tape (CT)

74LVT

e4

yes

Active

1 (Unlimited)

64

EAR99

-

-

-

2.7V~3.6V

DUAL

GULL WING

260

-

3.3V

0.5mm

-

-

74LVT18512

64

-

-

-

3.3V

Non-Inverting

-

-

-

-

18-Bit

-

-

-

-

-

-

MICROPROCESSOR CIRCUIT

18

20 ns

18mA

20 ns

-

Transceiver

Bidirectional

-

Scan Test Universal Bus Transceiver

-

-

-

-

-

-

-

-

-

-

-

-

1.2mm

17mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

SN74ALVCH16269DGGR
SN74ALVCH16269DGGR

Texas Instruments

12

-

Datasheet

-

ACTIVE (Last Updated: 2 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

252.792698mg

1

-40°C~85°C

Cut Tape (CT)

74ALVCH

e4

yes

Discontinued

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

-

TR

1.65V~3.6V

DUAL

GULL WING

260

1

1.8V

0.5mm

-

-

74ALVCH16269

56

12

-

-

-

Non-Inverting

3.6V

3.3V

-

-

12 ~ 24-Bit

-

50pF

3

-

24mA

-

-

24

6.2 ns

40μA

8.2 ns

ALVC/VCX/A

-

-

3-STATE

Registered Bus Exchanger

2V

-

-

-

POSITIVE EDGE

INDEPENDENT CONTROL

-

0.04mA

-

-

UNIDIRECTIONAL

N/A

1.2mm

14mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free

SN74ABT16501DGGR
SN74ABT16501DGGR

Texas Instruments

1991

-

Datasheet

-

ACTIVE (Last Updated: 6 days ago)

-

Surface Mount

Surface Mount

56-TFSOP (0.240, 6.10mm Width)

56

249.986095mg

1

-40°C~85°C

Cut Tape (CT)

74ABT

e4

yes

Discontinued

1 (Unlimited)

56

EAR99

Nickel/Palladium/Gold (Ni/Pd/Au)

WITH INDEPENDENT OUTPUT ENABLE FOR EACH DIRECTION

TR

4.5V~5.5V

DUAL

GULL WING

260

1

5V

0.5mm

-

-

74ABT16501

56

-

-

-

5V

Non-Inverting

-

5V

-

-

18-Bit

-

50pF

2

-

64mA

-

-

18

4.5 ns

-

6.5 ns

ABT

Transceiver

Bidirectional

3-STATE

Universal Bus Transceiver

-

-

0.064 A

4 ns

POSITIVE EDGE

INDEPENDENT CONTROL

-

76mA

-

-

-

N/A

1.2mm

14mm

6.1mm

1.15mm

No

-

ROHS3 Compliant

Lead Free