How Many Watts Is a 2835 SMD LED? Specs, Power Tiers & Selection Guide
The 2835 SMD LED is the highest-volume mid-power package in general lighting: just 2.8×3.5 mm, available in 0.1 W, 0.2 W, and 0.5 W tiers (driven at 30 mA, 60 mA, and 150 mA), and found everywhere from LED strips and bulbs to panel lights and tube lights. "How many watts is a 2835?", "2835 vs 5050 — which is better?", "Can a 2835 replace a 3528?" — this guide answers these questions with a complete selection method covering size, power tiers, electrical and optical specs, grade levels, and pricing differences.
1. 2835 LED Dimensions, Power and Family Position
Named after its footprint — 2.8 mm × 3.5 mm, about 0.8 mm thick — the 2835 is a top-emitting mid-power SMD LED. Its position in the lighting SMD family:
| Package | Size (L×W mm) | Typical power | Typical current | Typical use |
|---|---|---|---|---|
| 3528 | 3.5×2.8 | 0.06 W | 20 mA | Legacy strips, budget lighting (being replaced by 2835) |
| 2835 | 2.8×3.5 | 0.1 / 0.2 / 0.5 W | 30 / 60 / 150 mA | LED strips, bulbs, panel lights, tubes |
| 5050 | 5.0×5.0 | 0.2 W (3-die) | 60 mA | RGB color changing, strips, light boxes |
| 5730 | 5.7×3.0 | 0.5 / 1 W | 150 / 350 mA | High-brightness bulbs, downlights, industrial lighting |
The 2835 is the successor to the 3528/3014: similar size, but a large thermal pad with a heat-separated lead frame conducts heat straight from the die to the PCB. That thermal structure — far better than the bent-lead frames of 3528 and 5050 — is exactly why a 2835 can run at 0.5 W while a 3528 tops out at 0.06 W.
2. How Many Watts Is a 2835 LED? Three Power Tiers
This is the most-asked question from buyers and engineers. The 2835 has no single wattage — it comes in three common tiers:
| Power tier | Drive current | White luminous flux (typical) | Typical use |
|---|---|---|---|
| 0.1 W | 30 mA | 10–15 lm | Low-voltage strips, accent lighting, backlights |
| 0.2 W | 60 mA | 20–25 lm | Standard strips and bulbs (the most common tier) |
| 0.5 W | 150 mA | 50–60 lm | High-brightness panels, tubes, commercial lighting |
Selection tip: don't run any tier at maximum current continuously. Leave a 10%–20% current margin — lumen maintenance and lifetime improve noticeably. At the same wattage, prefer higher efficacy (lm/W): a 0.2 W part at 130 lm/W is 30% brighter than one at 100 lm/W, and the energy gap adds up over years of operation.
3. Key Electrical and Optical Specifications
Electrical
| Parameter | Red / Yellow | Blue / Pure green / White | Notes |
|---|---|---|---|
| Forward voltage VF | 1.8–2.3 V | 2.8–3.6 V | Design white-LED drivers around 3.0–3.4 V |
| Forward current IF | Per tier: 30/60/150 mA | Same | Leave a 10%–20% margin |
| Reverse voltage VR | 5 V | 5 V | Reverse connection may destroy the die |
| Beam angle | 120° | 120° | Standard flat package |
Optical
- CCT (white): warm white 2700–3500 K (homes, hotels), neutral/cool white 6000–6500 K (offices, commercial), cool white 7000 K+ (special uses). Strips and residential lighting are dominated by warm and neutral white.
- CRI (Ra): standard Ra70–75, mid-grade Ra80, high-grade Ra90+ (R9>50). Use Ra80 minimum for residential, commercial and hospitality; Ra90+ for museums and fresh-food lighting.
- Wavelength (single color): red 620–625 nm, pure green 520–525 nm, blue 465–470 nm — for decoration, signaling, and horticulture.
- Efficacy: mid-grade finished fixtures commonly reach 100–130 lm/W; high-grade parts go higher. Always check the test conditions behind a datasheet lumen figure (current, temperature, phosphor conversion losses).
4. 2835 vs 3528, 5050 and 5730
| Item | 3528 | 2835 | 5050 | 5730 |
|---|---|---|---|---|
| Power per LED | 0.06 W | 0.1–0.5 W | 0.2 W | 0.5–1 W |
| Thermal structure | Bent leads, high resistance | Large thermal pad, excellent | Plastic-wrapped leads, average | Heat-separated, very good |
| Brightness per LED | 6–8 lm | 10–60 lm | 16–22 lm | 50–70 lm |
| Drop-in replacement? | No — different pads, board redesign needed | — | No — different size | No — different size |
| Status | Phasing out | Mainstream | Mainstream for RGB | Mainstream for high brightness |
In one sentence: the 2835 is the sweet spot of cost and thermal performance — first choice for single-color lighting; pick 5050 for RGB color changing; pick 5730 for higher brightness per LED; and don't design-in 3528 for new projects.
5. Standard vs Mid-Grade vs High-End: What Changes, and What's the Price Gap?
2835 LEDs with the same markings can cost several times apart. The difference comes down to die, lead frame, bonding wire, phosphor, and quality standards:
| Item | Standard (low-end) | Mid-grade | High-end |
|---|---|---|---|
| Die | Small domestic die | Branded domestic die | Imported/custom large die |
| Lead frame | Iron or brass | Copper | Anti-sulfur copper / EMC frame |
| Bonding wire | Alloy wire | Gold wire | Gold wire with zener ESD protection |
| Phosphor | Generic, visible color drift | Branded, SDCM ≤5 | Premium, SDCM ≤3, high-CRI recipe |
| CRI | Ra70 | Ra80 | Ra90+ (R9>50) |
| Quality standards | Basic electrical specs + RoHS only | RoHS/REACH, IEC 62717 performance standard, JEDEC J-STD-020 moisture/reflow rating, factory burn-in sampling with full binning records | Mid-grade plus: full LM-80 lumen maintenance report, 85°C/85%RH damp-heat test, thermal shock, anti-sulfur testing, HBM 4–8 kV ESD, full batch traceability |
| Consistency / lifetime | Visible drift, fast early decay | Controlled, ~25,000-hour class | 36,000–50,000-hour class with LM-80 data |
| Typical use | Budget strips, toy lights, giveaways | Residential lighting, standard strips, bulbs | Commercial lighting, export fixtures, premium projects |
A few standards worth understanding:
- LM-80: the IES lumen-maintenance test — 6,000+ hours of continuous operation at 55°C/85°C/105°C while recording the decay curve. It is the most rigorous basis for any "50,000-hour lifetime" claim, but the test is slow and expensive, so usually only high-end products carry it. Indicator-class LEDs (like the 0603) are not lighting products and don't require it.
- IEC 62717: the international performance standard for LED modules — it defines how flux, chromaticity and CRI are measured, and is the benchmark for judging datasheet credibility.
- Anti-sulfur testing: trace sulfur in the air blackens silver-plated frames and collapses lumen output — a critical treatment for LED strips and outdoor lighting.
- SDCM (color tolerance): ≤5 SDCM is visually uniform; ≤3 SDCM suits demanding commercial projects.
Toy-grade, consumer-grade, industrial-grade — how do they map?
The 2835 is a lighting device, so its application tiers map roughly like this (2835s are rarely used in automotive; car indicators typically use small packages like the 0603):
| Tier | Config | Standards | Typical use |
|---|---|---|---|
| Toy-grade | Low-end | RoHS only, no reliability testing | Light-up toys, gift lights |
| Consumer-grade | Mid-grade | RoHS/REACH, IEC 62717, J-STD-020, factory burn-in sampling with binning records | Residential lighting, standard strips, bulbs |
| Industrial-grade | High-end | Consumer-grade plus full LM-80 report, 85/85 damp heat, thermal shock, anti-sulfur, batch traceability | Industrial & outdoor lighting, commercial projects, export orders |
Price gap: as a rule of thumb, mid-grade costs 2–3× the low-end, and high-end 5–10×. For a 0.2 W white 2835: roughly ¥20–30 per thousand pieces at the low end, ¥50–60 mid-grade, and ¥100+ for high-CRI imported-die parts (market reference only — actual quotes prevail).
How to choose: mid-grade minimum for domestic residential lighting; for project and export orders, verify SDCM data and the maker's lifetime-test basis (an LM-80 report is a plus); never save a few cents on low-end parts for strip projects — strips are dense, and one dead LED darkens a whole section. Note that HC-LED's 2835 LEDs are mid-grade and above only — we don't make low-end parts. The low-end column exists to help buyers see what really sits behind market price gaps.
6. Five Steps to Select a 2835 LED
- Set the power tier: work back from the fixture's lumen target; 0.2 W is the strip staple, 0.5 W suits high-brightness panels.
- Set CCT and CRI: warm white Ra80 for homes, neutral white Ra80–90 for commercial, Ra90+ for special cases.
- Check the electrical design: drive white LEDs at VF 3.0–3.4 V with constant current, 10%–20% margin; use metal-core PCBs or generous copper for heat spreading.
- Pick the grade: mid-grade minimum, with SDCM ≤5 and complete binning records.
- Audit the maker: check burn-in sampling data and binning records (an LM-80 report is a plus); for strips and outdoor use also ask about anti-sulfur treatment; for export orders verify RoHS/REACH and IEC 62717 test bases.
7. Soldering and Handling Notes
- Reflow peak ≤ 260 °C within 10 seconds. Most 2835 parts are MSL 2a–3 — use within 168 hours of opening; bake at 60 °C if moisture is suspected.
- Rework iron ≤ 350 °C, no more than 3 seconds per joint.
- Thermal management decides lifetime: prefer metal-core boards, maximize copper area, avoid tight spacing. Every 10 °C drop in internal temperature roughly doubles LED life.
- Use constant-current drivers; avoid capacitive-drop direct drive (high ripple accelerates lumen decay and causes flicker).
8. FAQ
Q: How many watts is a 2835 LED? There's no single wattage. Common tiers are 0.1 W, 0.2 W, and 0.5 W, driven at 30 mA, 60 mA, and 150 mA respectively. The 0.2 W (60 mA) tier is the most common for LED strips and bulbs. Choose the tier based on the fixture's brightness target and thermal design.
Q: Can a 2835 replace a 3528? Not as a drop-in. Although the numbers are just swapped (2.8×3.5 vs 3.5×2.8 mm), the pad layouts and thermal structures differ — the 2835 uses a large thermal-pad design. A board redesign for 2835 brings clear gains in brightness and heat dissipation, which is why the 2835 has fully replaced the 3528.
Q: 2835 vs 5050 — which is better? Different jobs. For single-color lighting (strips, bulbs, panels), pick the 2835: better thermals and value. For RGB color changing, pick the 5050: three dies in one package for full color. At equal power, the 2835 beats the 5050 on efficacy and lifetime in single-color use.
Q: How do I tell the positive and negative of a 2835 LED? Check the back of the package: the side with the green dot or T-shaped mark is the cathode (negative). Internally, the larger frame pad is usually the cathode too. The safest way is a multimeter on diode mode: red probe to anode, black to cathode, and the LED glows faintly when connected correctly (white LEDs show ~2.8 V+; some meters can't light them, which is normal).
Q: How many 2835 LEDs per meter for a strip? Common specs are 60 LEDs/m and 120 LEDs/m. A 60 LEDs/m strip at the 0.2 W tier draws about 12 W/m for general ambience; 120 LEDs/m gives more uniform light with no dark spots, ideal for exposed installations without diffusers. For close-range cabinet and display lighting, choose 120 LEDs/m.
Q: What is an LM-80 report, and does it matter? LM-80 is the international lumen-maintenance test: 6,000+ hours at three temperatures while recording the decay curve — the most rigorous basis for lifetime claims. But the test is slow and costly, so only some high-end makers run it. Most manufacturers (including HC-LED) control lifetime and consistency through factory burn-in sampling and binning records instead. If a project or export order explicitly requires LM-80, confirm availability with the supplier directly.
9. Final Words
2835 selection comes down to four things: power tier (0.1/0.2/0.5 W), CCT and CRI, drive-current margin, and grade level. HC-LED (Hongcheng Optoelectronics) specializes in LED diodes and SMD LEDs. We stock the full 2835 white CCT range (warm/neutral/cool) plus single colors, insist on mid-grade-and-above builds with no low-end line, support custom CCT/CRI/brightness binning, and ship with burn-in sampling data, free samples, and datasheets. For 2835 datasheets or samples, visit our TOP LED product series or contact our engineering team.
