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How to Use CHR0805-1 220kOhm Resistors in Electronic Circuits (South Africa)

Learn to select and use CHR0805-1 220kOhm SMD resistors for prototyping, repairs, and engineering. Covers specs, calculations, circuit examples, and local sourcing at Communica.

Published:February 21, 2026

4 min read

Image supplied by 123RF

Key Specifications Explained

Understand wattage, tolerance, and package details for CHR0805-1 220kOhm resistors.

Circuit Use & Calculations

See practical voltage divider and pull-up examples using 220kOhm SMD resistors.

Local Sourcing & Substitution

Find stock, related specs, and brand options at Communica branches and online.

Overview: What Is a CHR0805-1 220kOhm Resistor?

Resistors are crucial passive components used to control current, divide voltages, and set operating points in all sorts of electronics. The CHR0805-1 220kOhm is an 0805-sized surface mount device (SMD) resistor with a resistance value of 220,000 ohms. This SMD type is widely used due to its small footprint and reliability in modern PCBs, including prototyping, IoT projects, repairs, and commercial assemblies.

Typical use cases in South Africa include universities and FET colleges teaching SMD soldering, local PCB repairs, and OEM projects where compact, standardized passives are needed.

Technical Specifications and Standards

Feature	CHR0805-1 220kOhm
Resistance	220,000 Ohm (220kOhm)
Tolerance	1% (E96 Standard)
Power Rating	1/8 Watt (0.125W)
Size	0805 (2.0mm x 1.25mm)
Mounting	Surface Mount (SMD/SMT)
Temperature Coefficient	Typically 100 ppm/ degreesC
Packaging	Tape/Reel or Cut-tape

These resistors comply with typical IEC and JEDEC industry standards for SMD passives. The 0805 footprint is widely compatible with automated assembly systems used throughout South African OEMs and tertiary labs.

Where and Why to Use 220kOhm SMD Resistors

Voltage dividers for signal scaling or ADC reference inputs.
Pull-up or pull-down resistors for microcontroller GPIOs or logic inputs.
Biasing in analog (op-amp) and RF applications, provided parasitic capacitance is not critical.
RC timing circuits and filters (often paired with lower value capacitors).
Low-power LED current limiting for status indicators.

220kOhm is considered a high-value resistor, allowing minimal current draw and is well suited for battery-powered and low-leakage circuits frequently built by South African makers and students.

Package Size and Soldering Considerations

The 0805 size strikes a balance between ease of hand soldering (using tweezers and fine-tipped tools) and density for automated pick-and-place machines. In academic labs and field repairs, these can be soldered or reworked with a temperature-adjustable soldering iron (350-370 degreesC recommended), fine solder (<=0.5mm), and ESD-safe tweezers.

Calculations: Sizing, Power Rating, and Example Circuits

Always verify that the resistor can safely dissipate the expected power. Calculate power using Ohm's Law:

Formula:
P = V2 / R or P = I2 x R

With a 0.125W (1/8W) CHR0805-1 resistor, keep the actual dissipation well below the rating, ideally at or under 0.1W for reliability in warm South African environments.

Example: If used as a pull-up to 3.3V:
P = (3.3V)2 / 220,000Ohm ~ 0.00005W (well within spec)

Sample Application: Voltage Divider

Suppose you need to halve a 3.3V logic signal to ~1.65V for an ADC input. Using two identical 220kOhm resistors in series:

+3.3V
 |
[220kOhm] R1
 |
------ Output (1.65V)
 |
[220kOhm] R2
 |
GND

The divided voltage V_out = V_in x (R2 / [R1+R2]) = 3.3V x (220k/440k) ~ 1.65V

For digital logic, ensure the divider's output impedance is low enough for your ADC input (check datasheet recommendations).

Troubleshooting Tips for SMD 220kOhm Usage

Double-check resistor orientation using the component code (if laser marked).
Cold solder joints: Retouch connections showing intermittent readings.
Measure in-circuit resistance with power off-unwanted parallel paths may affect readings. Remove one end if needed.
If a circuit is unresponsive, verify you haven't accidentally swapped the part for a 220Ohm or 2.2MOhm SMD (decoding can be tricky).
For harsh SA environments (dust, humidity), consider conformal coating or cleaning flux residue for reliability.

Availability and SA Buying Advice:
CHR0805-1 220kOhm and related values are typically available from Communica's Centurion warehouse, Pretoria, and Cape Town branches, as well as sub-distributors. You can browse resistors by value or package, and check stock or request VAT invoices for institution/industry orders.

Sourcing, Brands, and Alternatives

CHR0805-1 is supplied alongside equivalent parts from preferred brands like Yageo, KOA Speer, and Panasonic.
Look for the same package (0805), resistance, and power ratings for direct substitution in repairs.
For prototyping or less space-constrained builds, 1206 or 0603 SMD sizes, or even leaded equivalents, can be used if design allows.
Bulk packaging (tape/reel) simplifies automated assembly for industry users.

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How to Use CHR0805-1 220kOhm Resistors in Electronic Circuits (South Africa)

Key Specifications Explained

Circuit Use & Calculations

Local Sourcing & Substitution

Communica South Africa

Overview: What Is a CHR0805-1 220kOhm Resistor?

Technical Specifications and Standards

Where and Why to Use 220kOhm SMD Resistors

Package Size and Soldering Considerations

Calculations: Sizing, Power Rating, and Example Circuits

Sample Application: Voltage Divider

Troubleshooting Tips for SMD 220kOhm Usage

Sourcing, Brands, and Alternatives

Sources

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