665K OHM 0.25W 1206 1% SMD RESISTOR

If your board needs a 665k ohm resistor, and the old part is a 1% 0.25W chip in a 1206 body, this is the part to order. It is a 665k ohm resistor in a small rectangular surface-mount body, built for stable voltage and current regulation in electronic circuits and power management systems. It fits voltage dividers, filtering, and signal conditioning jobs that need a fixed 665K value at up to 0.25W. It does not fit jobs that need a different resistance value, a through-hole body, or more than 0.25W of power. Check the checks below before you order, so the value, the power, the voltage, and the body all match your board.

This is an original, high-quality part.

What it does

A resistor limits current and drops voltage in a circuit. A chip resistor does that job as a small flat part that solders straight onto the pads of a board, with metal ends that make the contact. This 665k ohm 1% resistor holds its 665K value within 1%, so a board that calls for 665K gets between 658.35K and 671.65K. The high value is the point here: at the same voltage, a 665K part passes far less current than a low-value part, which is why it fits voltage division and signal conditioning rather than heavy load work. The 1206 body is about 3.1 mm long, so it fits boards where a larger part would not, while still handling a quarter of a watt.

Repair techs use a part like this as a 665k 1206 resistor for voltage regulation, where it takes a share of the voltage so the next stage sees the right level, and for signal conditioning, where a fixed high resistance shapes or scales a signal without loading it down. It also fits circuit protection, where a steady high value keeps a fault current inside safe limits. You can check the value from the marking: the 4-digit value code for this part is 6653, which reads as 665 followed by 3 zeros, or 665,000 ohm.

Key features

• 665K Ohm fixed resistance, ±1% tolerance
• 0.25W power rating at 70°C ambient
• Thick film chip construction, surface mount
• 1206 body: about 3.10 mm × 1.60 mm × 0.55 mm
• Maximum working voltage 200V (see the power-based limit in the checks)
• Temperature coefficient ±100 ppm/°C
• Wide temperature range: −55°C to +155°C
• 4-digit value code 6653

Checks before you order

• Value: your board list must call for 665K. A nearby value is not the same part — if your board needs a different value, stop and check the board list again. A 10K part in the same 1206 body is a different value for a different job, not a swap for this one.
• Power and heat: the power this part turns into heat must stay at or below 0.25W, and that 0.25W counts only up to 70°C ambient — above that, the safe power drops, so check the derating for your real working temperature. Work out the power from your real voltage and current (power = voltage × current) and keep it inside 0.25W with room to spare.
• Voltage: the voltage across this part must stay at or below the 200V series cap. From power alone the figure would be higher (about 408V at 0.25W), so the 200V cap is the limit that binds — stay below it. Above that, this part is the wrong pick.
• Tolerance: the real value may sit up to 1% away from 665K. If your circuit needs tighter than 1%, this part is the wrong pick — do not hope the part you get sits near the middle.
• Body and fit: your board must take a 1206 surface-mount body. Measure the old part and match it against the pads and the space on your board. The series body is about 3.10 mm long, 1.60 mm wide, and 0.55 mm high — if your old part is much smaller, check the board list again before you order. A 0 ohm jumper in the same 1206 body is a jumper, not a resistor, and is a different job.
• Fit for the job: if your circuit only needs a fraction of a quarter of a watt, this part still works. Match the value first, then the power, then the body — a through-hole resistor is the wrong shape for a surface-mount board, even if the value matches.

Specifications

All figures below are from the maker series documents for this chip resistor family. No figure here was guessed. The maker of the exact part on this page is not stated on the live page, so the publisher should confirm the series figures against the Download file at publish time (see the gates note).

Other names for the same part (good to know)

Shoppers and repair techs call this same part by a few names. 665k ohm is the plain name from its value. 665k ohm resistor is the name buyers use with the unit spelled out. 665k 1206 resistor is the name buyers use when the body size matters. SMD resistor is the name for its surface-mount style. 665k ohm 1% is the short name that carries the value and the tolerance together. If your board list calls for 665K at 0.25W with 1% tolerance in a 1206 body, this page is the right match. Do not judge by size alone — check the value, the power, and the tolerance too.

Frequently Asked Questions

What does 665K mean?

It means 665,000 ohms of resistance. K stands for kilo, which means one thousand, so 665K is 665 × 1,000 ohms.

What does 1% mean, and what does 0.25W mean?

1% is the tolerance: the real resistance may sit up to 1% above or below 665K, so between 658.35K and 671.65K. 0.25W is the power rating: the most power the part can turn into heat without damage, rated at 70°C ambient, with less allowed as it gets hotter.

What is the 6653 marking on the body?

It is the 4-digit value code for this part: 665 stands for the digits 665, and the last 3 means three more zeros, so 6653 means 665,000 ohms. The EIA-96 code for the same value is 80D, where 80 stands for 665 and D means ×1,000.

Can I use this part above 200 V if the power is small?

No. The maximum working voltage is 200 V, and it applies even when the power is tiny. At 665K the current is always small, so voltage, not power, is the limit to watch.

How do I fit a 1206 chip resistor?

Solder it onto the matching pads on the board — it has no leads, so it sits flat on the pads. Check the pad spacing against the 3.1 mm body before you solder, use a fine tip and a small amount of solder, and do not overheat the part.

What is the price of this part?

Check the live price on the website. The price shown on the product page is the current one.

Use note kept from the old page: this part was listed before as a 665K ohm 0.25W SMD resistor for stable and reliable performance in electronic circuits, for accurate voltage and current regulation, stable signal processing, and circuit protection in high-performance electronics and power management systems, used in solar inverters for voltage regulation and circuit protection, voltage dividers, filtering, and signal conditioning, in high-density PCB designs — and that use still stands.