SMD Economy Trimmers Type 3121 Series Type 3121 Series Characteristics - Electrical Resistance Range: 100R to 1M (Linear) Resistance Values: 1, 2, 5 in each decade Resistance Tolerance: ± 25% Temperature Coefficient of Resistance: ±250ppm/°C ( -20°C ~ +85°C) Continuous Operating Voltage: 50 Volts DC maximum Power Rating @ 70°C: 0.15 Watt Effective Electrical Angle: 260° ±20° Is this the ultimate in small Characteristics - size electro-mechanical components? Mechanical Probably not, but certainly so for some long time to come. Just 2.2mm x Mechanical Adjustment: Continuous 2.7mm in size, this tiny surface mount Rotational Torque: 1 to 15 mNm trimmer is offered in a range of values Rotational Life: ±15% maximum change (20 cycles) and available from Tyco Electronics Packaging: 3000 pieces per 7" reel NOW. The 3121 covers a board area of approx. 6mm square - about the same size as a 12:06 flat chip. Its adjustment Characteristics - rotor has an unbroken perimeter with Environmental internal driver slot allowing standard vacuum nozzles and trim tools Operating Temperature: -40°C to +100°C to be used. Storage Temperature: -10°C to +40°C Storage Time: 6 Months For maximum shelf life do not disturb polythene sleeve until you are ready to use potentiometers. Key Features � Consumes Minimal Board Space Dimensions � Taped and Reeled (8mm) � 50V Operating Maximum � Wide Value Range � Attractively Priced � Suited to Pick and Place � 0.15 Watts Power Rating � Stable Alumina Substrate Recommended Land Pattern Circuit Diagram 13 2 Literature No. 1773124 Dimensions are shown for Dimensions are in millimetres Specifications subject to www.tycoelectronics.com Issued: 08-05 reference purposes only. unless otherwise specified. change. passives.tycoelectronics.com SMD Economy Trimmers Type 3121 Series Application Notes- Suggested Circuit Configuaration The best results are obtained when using the potentiometer as a voltage divider see diagram circuit A below. Current controller type circuit B below is not a recommended application for this potentiometer. Anode Oxidation 3 2 1 When D.C. current is is used and the trimmer is to remain in one set position for a long period, it is good practise to connect the negative line to the resistance element and the positive line to the wiper terminal. With the polarity reversed, particularly in moist conditions, it is possible for the surface oxidation of the contact to cause a resistance increase. Notes Solder and Flux deposited onto the surface of the resistive element, can cause damage to the wiper. Please ensure potentiometer is fully cleaned prior to adjustment. The use of Lock Paint is not recommended for the 3121 Series How to Order 3121 X 102 P Common Part Orientation Resistance Value Tolerance The first two digits are signifigant figures of resistance value and the X - Terminals 1 and 3 third denotes the number Auto Adjust Trimmer away from the P - 25 % of zeros following. sprocket holes e.g. 1K: 102 5K: 103 100K: 104 Literature No. 1773124 Dimensions are shown for Dimensions are in millimetres Specifications subject to www.tycoelectronics.com Issued: 08-05 reference purposes only. unless otherwise specified. change. passives.tycoelectronics.com