Trimmer Potentiometers

Part Number	Description / PDF	Quantity
3306K-1-201 J.W. Miller / Bourns	TRIMMER 200 OHM 0.2W PC PIN SIDE	0
3296Y-1-473 J.W. Miller / Bourns	TRIMMER 47K OHM 0.5W PC PIN TOP	0
TC33X-2-303G J.W. Miller / Bourns	TRIMMER 30K OHM 0.1W J LEAD TOP	0
3214X-2-200E J.W. Miller / Bourns	TRIMMER 20 OHM 0.25W GW TOP ADJ	0
3262P-1-501 J.W. Miller / Bourns	TRIMMER 500OHM 0.25W PC PIN SIDE	0
3361S-1-104GLF J.W. Miller / Bourns	TRIMMER 100K OHM 0.5W GW SIDE	633
3262P-1-503 J.W. Miller / Bourns	TRIMMER 50KOHM 0.25W PC PIN SIDE	0
3386G-1-474 J.W. Miller / Bourns	TRIMMER 470K OHM 0.5W PC PIN TOP	0
3223G-1-502E J.W. Miller / Bourns	TRIMMER 5K OHM 0.125W GW SIDE	87
3339P-1-104 J.W. Miller / Bourns	TRIMMER 100K OHM 0.5W PC PIN TOP	0
3329X-1-103 J.W. Miller / Bourns	TRIMMER 10K OHM 0.5W PC PIN SIDE	0
3386P-1-203 J.W. Miller / Bourns	TRIMMER 20K OHM 0.5W PC PIN TOP	284
3339H-1-201LF J.W. Miller / Bourns	TRIMMER 200 OHM 0.5W PC PIN TOP	0
3386H-1-203TLF J.W. Miller / Bourns	TRIMMER 20K OHM 0.5W PC PIN SIDE	0
3299Y-1-205LF J.W. Miller / Bourns	TRIMMER 2M OHM 0.5W PC PIN TOP	54
3329W-1-103LF J.W. Miller / Bourns	TRIMMER 10K OHM 0.5W PC PIN SIDE	167
3299W-1-201LF J.W. Miller / Bourns	TRIMMER 200 OHM 0.5W PC PIN TOP	1204
3314S-1-501G J.W. Miller / Bourns	TRIMMER 500OHM 0.25W J LEAD SIDE	0
3386X-1-223LF J.W. Miller / Bourns	TRIMMER 22K OHM 0.5W PC PIN SIDE	0
3362P-1-200 J.W. Miller / Bourns	TRIMMER 20 OHM 0.5W PC PIN TOP	0

Trimmer Potentiometers

1. Overview

Trimmer potentiometers (trimpots) are adjustable resistors designed for infrequent calibration and tuning of electronic circuits. Unlike standard potentiometers, trimpots are optimized for precision adjustments during device manufacturing or maintenance. They play a critical role in modern electronics by enabling fine-tuning of voltage division, signal levels, and circuit parameters in compact spaces.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Rotary Trimmer	Adjustment via rotational knob (single-turn -turn)	Power supply calibration, amplifier gain control
Slide Trimmer	Linear slider mechanism for resistance adjustment	Audio equipment balance control, sensor signal trimming
Surface Mount (SMD) Trimmer	Miniaturized design for PCB surface mounting	Mobile devices, IoT sensors
Digital Trimmer	Electronic adjustment via digital interface (I2C/PWM)	Smart instrumentation, automated calibration systems

3. Structure and Components

Typical trimpot construction includes:

Resistive Element: Cermet, carbon composition, or conductive plastic materials
Adjustment Mechanism: Precision screw-driven wiper system (rotary) or linear slider
Enclosure: Flame-retardant thermoplastic or ceramic housing
Terminals: Tin-plated copper or brass for PCB mounting
Protection Coating: Epoxy or UV-curable resin for environmental resistance

4. Key Technical Specifications

Parameter	Description	Importance
Resistance Range	10 to 5M standard values	Determines adjustment resolution and circuit compatibility
Tolerance	5% to 20% depending on material	Impacts initial calibration accuracy
Power Rating	0.1-0.5W typical	Limits maximum current/voltage handling
Temperature Coefficient	100 to 200 ppm/ C	Defines stability across operating temperatures
Mechanical Life	500-5000 adjustment cycles	Determines maintenance interval requirements

5. Application Fields

Consumer Electronics: Smartphone sensor calibration, audio device equalization
Industrial Control: PLC signal conditioning, motor speed regulation
Medical Devices: Diagnostic equipment parameter tuning, implantable device calibration
Automotive: ECU sensor signal adjustment, dashboard display brightness control
Aerospace: Avionics system gain adjustment, navigation equipment calibration

6. Leading Manufacturers and Products

Manufacturer	Key Products	Technical Highlights
Bourns Inc.	3296 series (Precision Cermet)	0.5% tolerance, 20-turn adjustment
Vishay Precision Group	Vishay Dale S1A series	Hermetically sealed, MIL-STD-202 qualified
TT Electronics	PVH series (High-Voltage)	500V rating, 10M maximum resistance
Ohmite Mfg. Co.	789 series (High-Power)	2W rating, aluminum heatsink design

7. Selection Recommendations

Key considerations include:

Environmental Factors: Operating temperature (-55 C to +155 C), humidity resistance
Adjustment Requirements: Single-turn vs multi-turn based on precision needs
Mounting Type: Through-hole vs SMD depending on PCB space constraints
Compliance: RoHS/REACH regulations for hazardous material restrictions
Cost-Performance Balance: Cermet (mid-range), carbon (budget), conductive plastic (high-end)

8. Industry Trends Analysis

Emerging trends shaping trimpot development:

Miniaturization: 0402 package size SMD trimpots for wearable electronics
Digital Integration: I2C-programmable trimpots with non-volatile memory
Material Innovation: Graphene-enhanced resistive elements for improved stability
Automated Calibration: Robotics-compatible adjustment interfaces for mass production
Environmental Durability: IP67-rated sealed trimpots for harsh industrial environments