RC70C-1K37CBPB - Welwyn Components, Ltd.

Precision Metal

Film Resistors

RC series

•CECC released products with low

TCRs over a wide resistance range

•Resistance tolerance down to 0.05%

•Express delivery available

•Low noise and negligible voltage coefficient

General Note

Welwyn Components reserves the right to make changes in product specification without notice or liability.

All information is subject to Welwyn’s own data and is considered accurate at time of going to print.

Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com

173

RC55 RC65 RC70 Notes

Commercial

Power rating at 70°C watts 0.25 0.5 1.0

Resistance range ohms 1R to 4M 1R to 4M 1R to 10M

Limiting element voltage volts 350 350 500

Isolation voltage volts 500 500 700

TCR (20 to +70°C) & codes ppm/°C 5(V), 10(T), 15(Y), 25(D), 50(C) & 100(Z) See resistance

Resistance tolerance % 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions

Electrical Data

Issue B · 03.02

A subsidiary of

TT electronics plc

Welwyn Components

Approved CECC 40101-004 H J K K L

Power rating at 70°C watts 0.063 0.125 0.25 0.25 0.5

Resistance range ohms 1R to 1M 1R to 1M 1R to 1M 10R to 1M 10R to 1M

Limiting element voltage volts 200 200 250 250 350

Isolation voltage volts 280 280 350 350 500

TCR & codes ppm/°C 15(Y), 25(D), 50(C) & 100(Z) See resistance

Resistance tolerance (code) % 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions

Approved CECC 40101-804 A B B C

Power rating at 70°C watts 0.125 0.25 0.25 0.5

Resistance range ohms 1R to 1M 1R to 1M 10R to 1M 10R to 1M

Limiting element voltage volts 200 250 250 350

Isolation voltage volts 280 350 350 500

TCR & codes ppm/°C 15(T), 25(E) & 50(C) See resistance

Resistance tolerance (code) % 0.05(W), 0.1(B), 0.25(C), 0.5(D) & 1(F) restrictions

Standard values E24, E96 preferred Any value

Thermal impedance °C/watt 110 70 60 to order

Ambient temperature range °C -55 to +155

CECC 40101-004 CECC 40101-804

*Actual Performance

Requirements Requirements Maximum Typical

Load at commercial rating: 1000 hours at 70°C ∆R% 0.3 0.1

Load at CECC rating: 1000 hours at 70°C ∆R% 0.5 0.5 0.3 0.05

Dry heat: 1000 hours at 155°C ∆R% 0.5 0.5 **1.0 0.15

Shelf life: 12 months at room temperature ∆R% Not specified Not specified 0.1 0.03

Derating from rated power at 70°C Zero at 155°C 50% at 125°C

Short term overload ∆R% 0.1 0.1 0.1 0.02

Climatic ∆R% 0.5 0.5 0.3 0.1

Climatic category 55/155/56 55/125/56 55/155/56

Long term damp heat ∆R% 0.5 0.5 0.5 0.1

Temperature rapid change ∆R% 0.1 0.1 **0.2 0.05

Resistance to solder heat ∆R% 0.1 0.1 0.06 0.03

Vibration and bump ∆R% 0.1 0.1 0.06 0.02

Noise (in a decade of frequency) µV/V Not specified Not specified 1.0 0.1

Voltage coefficient of resistance ppm/V Not specified Not specified <1

Construction

A metal film is deposited onto a high quality ceramic former.

Nickel-plated steel caps are force fitted to the former and

termination wires are welded to the caps.

The resistor is adjusted to value by a helical cut in the film

and the body is protected with a specially formulated epoxy

coating.

Terminations

Material Solder coated copper wire

Strength The terminations meet the requirements of

IEC 68.2.21.

Solderability The terminations meet the requirements of

IEC 115-1, Clause 4.17.3.2.

Precision Metal

Film Resistors

RC series

Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com

174

Issue B · 03.02

Welwyn Components

Marking

Type reference, TCR code, resistance value and

tolerance code.

The resistance values conform to IEC 62.

Solvent Resistance

The body protection and marking are resistant to all normal

industrial cleaning solvents suitable for printed circuits.

Performance Data

Note: *An 0.01 ohm addition to be added to the performance claims of all resistors <10R.

** All products within the specified approved range meet CECC requirements.

Dimensions (mm) & Weight (g)

PCB Min.

mounting Bend

Type L max D max f min d nom centres Radius Wt. nom

RC55 7.2 2.5 30 0.6 10.2 0.6 0.24

RC65 10.0 3.7 30 0.6 12.7 0.6 0.40

RC70 15.5 5.5 30 0.8 18.4 1.2 1.15

Physical Data

Application Notes

Matched Sets and Networks

Welwyn has many years experience in the supply of matched

set of precision resistors.

Resistors can be supplied matched for tolerance and TCR

down to ±0.02% and ±2ppm/°C, either as separate resistors

or pre-assembled and encapsulated within a plastic box.

The individual resistors within a set or module can be

manufactured with a tolerance of ±0.05% and TCR of

±5ppm/°C.

A low inductance version is available at 1% tolerance.

For low inductance version add suffix N.

Packaging

The standard method of packaging RC55 resistors is taped in

ammo packs. Taped resistors on reel or loose packed

components can also be supplied by special request. The

standard packaging for RC65 and RC70 resistors is loose in

boxes. By special request the RC65 components can also be

supplied taped on reel or in ammo pack. In the case of tape

packed components the usable lead length is reduced by the

width of the tape.

f1f2

Body location f1 – f2 ≤ 1.4 mm

Standard Quantities Per Package

Type RC55 RC65 RC70

Small box 250 125 25

Large box 1000 500 250

Reel 5000 2500 -

Large ammo pack 1000 1000 -

175

Tolerance

TCR RC55 RC65 RC70

ppm/°C 0.05% .1 – .25% .5 – 1% 0.05% .1 – .25% .5 – 1% 0.05% .1 – .25% .5 – 1%

5 10 to 500k 10 to 500k 1 to 500k 10 to 500k 10 to 500k 1 to 500k 10 to 750k 10 to 750k 1 to 750k

10 10 to 1M 10 to 1M 1 to 1M 10 to 1M 10 to 1M 1 to 1M 10 to 1M 10 to 1M 1 to 1M

15 10 to 1M 5 to 1M 1 to 1M 10 to 1M 5 to 1M 1 to 1M 10 to 1M 10 to 2M 1 to 2M

25 10 to 1M 5 to 2M 1 to 2M 10 to 1M 5 to 2M 1 to 2M 10 to 1M 10 to 5M 1 to 5M

50 10 to 1M 5 to 2M 1 to 4M 10 to 1M 5 to 2M 1 to 4M 10 to 1M 5 to 10M 1 to 10M

100 10 to 1M 1 to 2M 1 to 4M 10 to 1M 1 to 2M 1 to 4M 10 to 1M 1 to 10M 1 to 10M

Precision Metal

Film Resistors

RC series Welwyn Components

Table of Resistance Restrictions

Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com Issue B · 03.02