Specifications given herein may be changed at any time without prior notice. Please confirm technical specifications before you order and/or use.

Contact our sales representatives before you use our products for applications including automotives, medical equipment and aerospace equipment.

Malfunction or failure of the products in such applications may cause loss of human life or serious damage.

www.koaglobal.com

THICK FILM（PRECISION）

RK73H FlatChipResistors(PrecisionGrade)

■Construction

Coating color：Black（1F, 1H）,

Blue（1E, 1J, 2A, 2B, 2E, W2H, W3A, W3A2）

■Features

・Wide lineup from 01005 to 2512 size.

・Excellent heat resistance and weather resistance are ensured by

the use of metal glaze thick film.

・Suitable for both flow and reflow solderings.

・Products with lead free termination meet EU-RoHS requirements.

EU-RoHS regulation is not intended for Pb-glass contained in

electrode, resistor element and glass.

・AEC-Q200 Tested (Exemption 1F).

■Reference Standards

 IEC 60115-8

 JIS C 5201-8

 EIAJ RC-2134C

① Protective coating

② Resistive film

③ Inner electrode

④ Ni plating

⑤ Solder plating

⑥ Ceramic substrate

L

c

c

W

t

d

③

②

①

④

⑤

⑥

■Type Designation

　Example

※2 With type A（1E,1J,2A,2B）only T is available as the terminal surface material.

※3 Products with gold plated electrodes are also available with 1E, 1J and 2A types（10Ω∼1MΩ）, so please consult with us.

※4 With type 1F, 1H, W2H, W3A, W3A2 only T is available as the terminal surface material.

The terminal surface material lead free is standard.

Contact us when you have control request for environmental hazardous material other than the substance specified by EU-RoHS.

For further information on taping, please refer to APPENDIX C on the back pages.

■Dimensions

EU

RoHS

※1 RK73H 2H, 3A and 3A2 are also still available (different“d”dimensions=0.4＋0.2

−0.1

mm)

■Ratings

Type

Power

Rating

Rated Ambient

Temp.

Rated Terminal

Part Temp.

T.C.R.

（×10−6/K）

Resistance Range（Ω）

Max. Working

Voltage

Max.

Overload

Voltage

Packaging & Q'ty/Reel（pcs）

D:±0.5%

E24・E96

F:±1%

E24・E96

TX

TBL

TCM※8

TPL・TP

TD

TE

1F

0.03W

70℃

—

±200

—

100k～2M※5

20V

30V

40,000

20,000

—

—

—

—

±250

10～91k※5

1H

0.05W

70℃

125℃

±200

10～1M

10～10M※5

25V

50V

—

—

15,000

—

—

—

±400

—

1～9.1※5

1E

0.1W

70℃

125℃

±100

10～1M

10～1M

75V

100V

—

—

—

TPL：20,000

TP ：10,000

—

—

±200

—

1～9.76

1.02M～10M

1J

0.1W

70℃

125℃

±100

1.02k～1M

1.02k～1M

—

—

—

TP ：10,000※7

5,000

—

±200

—

1.02M～10M

0.125W

±100

10～1k

10～1k

±200

—

1～9.76

2A

0.25W

70℃

125℃

±100

10～1M

10～1M

150V

200V

—

—

—

TP ：10,000※7

5,000

4,000※7

±200

—

1～9.76

±400

1.02M～10M

2B

0.25W

70℃

125℃

±100

10～1M

10～1M

200V

400V

—

—

—

—

5,000

4,000※7

±200

—

1～9.76

1.02M～5.6M

±400

5.62M～10M

2E

0.5W

70℃

125℃

±100

10～1M

10～1M

—

—

—

—

5,000

4,000※7

±200

—

1～9.76

1.02M～5.6M

±400

5.62M～10M

W2H

0.75W

70℃

125℃

±100

10～1M

10～1M

—

—

—

—

—

4,000

±200

—

1～9.76

1.02M～5.6M

±400

5.62M～10M

W3A

1W

70℃

125℃

±100

10～1M

10～1M

200V

400V

—

—

—

—

—

4,000

±200

—

1～9.76

1.02M～5.6M

±400

5.62M～10M

W3A2

2W※6

70℃

95℃

±100

10～1M

10～1M

200V

400V

—

—

—

—

—

4,000

±200

—

1～9.76

1.02M～5.6M

±400

5.62M～10M

Operating Temperature Range :−55℃∼＋125℃（1F）、−55℃∼＋155℃（1H・1E・1J・2A・2B・2E・W2H・W3A・W3A2）

Rated voltage＝ Power Rating×Resistance value or Max. working voltage, whichever is lower.

For flat chip jumper resistor, please refer to RK73Z series.

※5 The nominal resistance value for RK73H1F（10Ω≦R≦2MΩ）and RK73H1H（1Ω≦R≦9.1Ω, 1MΩ≦R≦10MΩ）is E24.

※6 If you use at the rated power, please keep the condition that the terminal of the resistor is below the rated terminal part temperature. Please refer to the derating curves based on the terminal temperature of right side on the next page.

※7 Standard packaging：TD(4mm pitch punch paper)

※8 Standard taping specification of 1H is TCM. Previously available“TC(10,000pcs/Reel)”is not recommended for new designs.

If any questions arise whether to use the“Rated Ambient Temperature”or the“Rated Terminal Part Temperature”in your usage conditions, please give priority to the“Rated Terminal Part Temperature”.

For more details, please refer to“Introduction of the derating curves based on the terminal part temperature”on the beginning of our catalog.

While using under high power, the temperature of the product may increase depending on the condition of heat dissipation from PCB.

Be sure to check the terminal part temperature as well as precautions to use on delivery specifications before use.

√￣￣￣￣￣￣￣￣￣￣￣

Type

（Inch Size Code）

Dimensions（mm）

Weight（g）

（1000pcs）

L

W

c

d

t

1F（01005）

0.4±0.02

0.2±0.02

0.10±0.03 0.11±0.03 0.13±0.02

0.04

1H（0201）

0.6±0.03

0.3±0.03

0.1±0.05 0.15±0.05 0.23±0.03

0.14

1E（0402）

1.0＋0.1

－0.05

0.5±0.05

0.2±0.1

0.25＋0.05

－0.1

0.35±0.05

0.68

1E AT（0402）

0.25±0.10

0.3±0.15

1J（0603）

1.6±0.2

0.8±0.1

0.3±0.1

0.3±0.1

0.45±0.1

2.14

1J AT（0603）

0.35±0.15

0.5±0.2

2A（0805）

2.0±0.2

1.25±0.1

0.4±0.2

0.3＋0.2

－0.1

0.5±0.1

4.54

2A AT（0805）

0.45±0.25

0.6±0.2

0.55±0.10

2B（1206）

3.2±0.2

1.6±0.2

0.5±0.3

0.4＋0.2

－0.1

0.6±0.1

9.14

2B AT（1206）

0.55±0.35

0.8±0.2

2E（1210）

2.6±0.2

0.5±0.3

0.4＋0.2

－0.1

15.5

W2H（2010）※1

5.0±0.2

2.5±0.2

0.65±0.15

24.3

W3A（2512）※1

6.3±0.2

3.1±0.2

37.1

W3A2（2512）※1

Characteristic

Nil：Standard

A：Heat shock

resistance※2

Terminal

Surface Material

T：Sn

G：Au※3

（L：Sn/Pb※4）

Taping

TX：4mm width-

　　1mm pitch plastic

　　embossed

TBL・TCM：

2mm pitch

press paper

TPL・TP：

2mm pitch

punch paper

TD：4mm pitch

punch paper

TE：4mm pitch

plastic

embossed

BK：Bulk

Nominal

Resistance

4 digits

Resistance

Tolerance

D：±0.5%

F：±1%

RK73H

2B

T

TD

1002

F

Product

Code

Power

Rating

1F：0.03W

1H：0.05W

1E：0.1W

1J：0.1W

0.125Ｗ

2A：0.25Ｗ

2B：0.25W

2E：0.5W

W2H：0.75W

W3A：1W

W3A2：2W※5

Jul. 2022

Specifications given herein may be changed at any time without prior notice. Please confirm technical specifications before you order and/or use.

　　

Contact our sales representatives before you use our products for applications including automotives, medical equipment and aerospace equipment.

Malfunction or failure of the products in such applications may cause loss of human life or serious damage.

www.koaglobal.com

■Performance

■Precautions for Use

・The substrate of chip resistors is alumina. Cracks may occur at the connection of solder (solder fillet portion) due to the difference of the coefficient of thermal

expansion from a mounting board when heat stress like heat cycle, etc. are repeatedly given to them. Care should be taken to the occurrence of the cracks when

the change in ambient temperature or ON /OFF of load is repeated, especially when large types of W2H/W3A/W3A2 which have large thermal expansion and

also self heating. By general temperature cycle test using glass-epoxy (FR-4) boards under the maximum/minimum temperatures of operating temperature range,

the crack does not occur easily in the types of 1F∼2E, but the crack tends to occur in the types of W2H/W3A/W3A2. The occurrence of the crack by heat

stress may be influenced by the size of a pad, solder volume, heat radiation of mounting board etc., so please pay careful attention to designing when a big change

in ambient temperature and conditions for use like ON/OFF of load can be assumed.

・Care should be taken that RK73H1F may be damaged when static electricity occurs and is applied in the equipment.

Test Items

Performance Requirements　ΔR±（％＋0.1Ω）

Test Methods

Limit

Typical　

Resistance

Within specified tolerance

—

25℃

T.C.R.

Within specified T.C.R

—

＋25℃/－55℃ and ＋25℃/＋125℃

Overload（Short time）

2

1：1F

0.5：others

Rated voltage×2.5 for 5s

（1E, 2B, W3A2：Rated voltage×2 for 5s）

Resistance

to soldering heat

1：1F～W3A（10Ω≦R≦1MΩ）

3：1H～W3A（R＜10Ω, R＞1MΩ）

0.5：1F～W3A（10Ω≦R≦1MΩ）

1：1H～W3A（R＜10Ω, R＞1MΩ）

260℃±5℃, 10s±1s

Rapid change of

temperature

1：1F, Characteristic「A」

　　（Heat shock resistance）

0.5：others

0.5：1F, Characteristic「A」

　　（Heat shock resistance）

0.3：others

Characteristic「Nil」

（Standard）：

　　ー55℃（30min.）/＋125℃（30min.）100 cycles

Characteristic「A」

（Heat shock resistance）：

　　ー55℃（30min.）/＋125℃（30min.）1000 cycles

Moisture resistance

2：1J, 2A, 2B

3：others

0.75：1J, 2A, 2B

1.5：1F

1：others

40℃±2℃, 90%～95%RH, 1000h

1.5h ON/0.5h OFF cycle

Endurance at 70℃ or rated

terminal part temperature

2：1J, 2A, 2B

3：others

0.75：1J, 2A, 2B

1：others

70℃±2℃ or rated terminal part temperature ±2℃ 1000h

1.5h ON/0.5h OFF cycle

High temperature exposure

1

0.5：1F

0.3：others

＋125℃, 1000h：1F

＋155℃, 1000h：1H, 1E, 1J, 2A, 2B, 2E, W2H, W3A, W3A2

■Derating Curve

■Temperature Rise

■One-Pulse Limiting Electric Power

100

80

60

40

20

0

-60 -40 -20

0204060

70

-55

80 100 120

125 155

140 160

Ambient temperature（℃）

1F

1H,1E,1J,2A,2B

2E,W2H,W3A（1W）,

W3A2（2W）

100

80

60

40

20

0

-60 -40 -20

0204060

70

-55

80 100 120

125 155

140 160

Terminal part temperature（℃）

1H,1E,1J,2A,2B,2E,

W2H,W3A（1W）

100

80

60

40

20

0

-60 -40 -20

0204060

95

-55

80 100 120

155

140 160

Terminal part temperature（℃）

あ1

あ1

Ambient temperature

Terminal part temperature

Terminal part temperature

RK73H W3A2

For resistors operated at an ambient temperature of

70℃ or higher, the power shall be derated in accordance

with the above derating curve.

When the terminal part temperature of the resistor exceeds the rated terminal part temperature shown above, the power

shall be derated according to the derating curve.

※Please refer to“Introduction of the derating curves based on the terminal part temperature” on the beginning of our

catalog before use.

0

10

20

30

40

50

60

70

80

90

100

0

25

50

75

100

RK73H 2A-2E

2E

2E

2B

2A

2B

2A

0

50

100

150

200

250

300

0

25

50

75

100

Power Rating（%）

RK73H W2H-W3A2

W3A2

W3A2

W3A

W2H

W3A

W2H

②：Terminal

①：Hot spot

Measurement condition

Room temperature: 25℃

PCB: FR-4t = 1.6mm

Cu foil thickness: 35µm

Power Rating（%）

0

10

20

30

40

50

60

0

25

50

75

100

1E

1J

1E

1J

1H

1F

1H

1F

RK73H 1F-1J

Power Rating（%）

The maximum applicable voltage is equal to the max. overload voltage.

Please ask us about the resistance characteristic of continuous applied pulse.

The pulse endurance values are not assured values,so be sure to check the

products on actual equipment when you use them.

Pulse Duration（ms）

0.001

0.01

0.1

1

10

100

1000

RK73H 1F-2A

RK73H 2B-W3A2

100

10

1

0.1

0.01

Pulse Duration（ms）

0.001

0.01

0.1

1

10

100

1000

1000

100

10

1

2A

1J

1E

1H

1F

W3A/W3A2

2H/W2H

2E

2B

Regarding the temperature rise, the

value of the temperature varies per

conditions and board for use since the

temperature is measured under our

measuring conditions.

Jul. 2022

Specifications given herein may be changed at any time without prior notice. Please confirm technical specifications before you order and/or use.

Contact our sales representatives before you use our products for applications including automotives, medical equipment and aerospace equipment.

Malfunction or failure of the products in such applications may cause loss of human life or serious damage.

www.koaglobal.com

Oct. 2022