Obsolescence Notice This product is obsolete. This information is available for your convenience only. For more information on Zarlink’s obsolete products and replacement product lists, please visit http://products.zarlink.com/obsolete_products/ DS2442 - 2.2 SR12D 1.2V PRECISION VOLTAGE REFERENCE The SR12D is a monolithic integrated circuit using the bandgap principle to provide a precise reference voltage of 1.23V. This reference device is packaged in a standard SOT-23 small outline package, making it ideal for all surface mount applications. SOT-23 Fig. 1 Pin connections (top view) FEATURES ■ Standard SOT-23 Surface Mount Package ■ Low Knee Current - Typically 80 µA ■ Low temperature Coefficient ABSOLUTE MAXIMUM RATINGS Reference current 2.5mA Operating temperature range Storage temperature range -40°C to + 85°C -55°C to +125°C Fig.3 SR12D external connections. Fig.2 SR12D circuit diagram NOTE: In order to achieve optimum operation, an electrolytic stabilising capacitor (CS > 1µF) should be connected between VREF and 0V as shown in Fig. 3. ELECTRICAL CHARACTERISTICS These characteristics are guaranteed over the following conditions (unless otherwise stated): Tamb = +25°C, IREF = 150µA, CS = 1µF Value Characteristic Units Symbol Min. Output voltage VREF Slope resistance (see note 1) RREF Turn-on (knee) current Recommended operating current range Temperature coefficient (see note 2) 1.193 ION IREF TCVREF Typ. 1.230 1.267 2.5 1.5 EN V Ω µA IREF = 150µA to 2.5mA 80 90 2.5 mA 40 125 ppm/°C 0°C to +70°C 120 ppm/°C -40°C to + 85°C 0.09 40 RMS noise voltage Conditions Max. 10 µV Turn on time tON 7 ms Turn off time tOFF 24 ms Turn on time tON 0.4 ms Turn off time tOFF 1.8 ms 1Hz to 25kHz IREF = 5mA SR12D NOTES 1. Slope Resistance (RREF) The slope resistance is defined as RREF = Change in VREF over specified current range The change in reference current 2. Reference Voltage Temperature Coefficient (TCVREF) This is the normalised reference voltage change over temperature , divided by the change in temperature. It is expressed in ppm/°C as follows: TCVREF = ∆VREF x 106 VREF x ∆T ppm/°C ∆T = temperature change in °C ∆VREF = change in reference voltage over temperature change ∆T. Fig.5 SR12D typical response time (not to scale) Fig.4 Typical reference characteristic Fig.6 Typical temperature characteristic of SR12D at IREF = 150µA 2 SR12D Fig.7 Derating curve 3 SR12D HEADQUARTERS OPERATIONS GEC PLESSEY SEMICONDUCTORS Cheney Manor, Swindon, Wiltshire SN2 2QW, United Kingdom. Tel: (0793) 518000 Fax: (0793) 518411 GEC PLESSEY SEMICONDUCTORS P.O. Box 660017 1500 Green Hills Road, Scotts Valley, California 95067-0017, United States of America. Tel: (408) 438 2900 Fax: (408) 438 5576 CUSTOMER SERVICE CENTRES • FRANCE & BENELUX Les Ulis Cedex Tel: (1) 64 46 23 45 Fax : (1) 64 46 06 07 • GERMANY Munich Tel: (089) 3609 06-0 Fax : (089) 3609 06-55 • ITALY Milan Tel: (02) 66040867 Fax: (02) 66040993 • JAPAN Tokyo Tel: (03) 5276-5501 Fax: (03) 5276-5510 • NORTH AMERICA Integrated Circuits and Microwave Products Scotts Valley, USA Tel (408) 438 2900 Fax: (408) 438 7023. Hybrid Products, Farmingdale, USA Tel (516) 293 8686 Fax: (516) 293 0061. • SOUTH EAST ASIA Singapore Tel: (65) 3827708 Fax: (65) 3828872 • SWEDEN Stockholm, Tel: 46 8 702 97 70 Fax: 46 8 640 47 36 • UK, EIRE, DENMARK, FINLAND & NORWAY Swindon Tel: (0793) 518510 Fax : (0793) 518582 These are supported by Agents and Distributors in major countries world-wide. © GEC Plessey Semiconductors 1994 Publication No. DS2442 Issue No. 2.2 January 1994 This publication is issued to provide information only which (unless agreed by the Company in writing) may not be used, applied or reproduced for any purpose nor form part of any order or contract nor to be regarded as a representation relating to the products or services concerned. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or service. The Company reserves the right to alter without prior knowledge the specification, design or price of any product or service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specific piece of equipment. It is the user's responsibility to fully determine the performance and suitability of any equipment using such information and to ensure that any publication or data used is up to date and has not been superseded. These products are not suitable for use in any medical products whose failure to perform may result in significant injury or death to the user. All products and materials are sold and services provided subject to the Company's conditions of sale, which are available on request. 4