GS-R12VXXX1.5 1.8W TO 7.5W STEP DOWN SWITCHING REGULATOR FAMILY PRELIMINARY FEATURE ■ MTBF 1 000 000 hours (Tamb=25)C) ■ 1.5A max output current 15V max input voltage 1.5V max drop-out voltage Not-latching overload and short circuit protection Thermal shutdown No heatsink required ■ ■ ■ ■ ■ DESCRIPTION The GS-R12VXXX1.5 series is a family of high efficiency step down switching voltage regulator, designed to replace linear regulators. ORDERING NUMBER: GS-R12VXXX1.5 The foot print of GS-R12V perfectly fits a standard TO220 package. Based on STM L5973 device, this non isolated family of regulators are suitable for the full spectrum of applications including telecom, industry, computer and distributed power system applications having a widely ranging input voltage. SELECTION CHART Type Ordering Number Output Voltage [V] Input Voltage [V] Output Ripple [mVpp] Efficiency [%] Notes GS-R12V0121.5 1.235 ± 3% 4.5 ÷ 15 35 68 Fixed output voltage GS-R12V0181.5 1.8 ± 4% 4.5 ÷ 15 35 72 Fixed output voltage GS-R12V0251.5 2.5 ± 4% 4.5 ÷ 15 35 76 Fixed output voltage GS-R12V0331.5 3.3 ± 4% 4.5 ÷ 15 35 82 Fixed output voltage GS-R12V0501.5 5.0 ± 4% 6.6 ÷ 15 35 85 Fixed output voltage October 2003 This is preliminary information on a new product now in development. Details are subject to change without notice. 1/5 GS-R12VXXX1.5 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Unit 16 V Vi DC Input Voltage Iout Maximum Output Current Tstg Storage Temperature Range -40 ÷ 105 °C Top Operating Ambient Temperature -25 ÷ 70 °C CONNECTION DIAGRAM AND MECHANICAL DATA 2/5 Value int. limit GS-R12VXXX1.5 PIN DESCRIPTION Pin Function 1 + input 2 GND 3 + output Description DC input voltage Common GND Regulated DC output voltage ELECTRICAL CHARACTERISTICS (Tamb=25)C, unless otherwise specified.) Symbol Parameter Test Condition Min. Typ. Max. Unit Temperature Stability Vi =Vo + 1.5V Io = 1.5A Io Output Current Vi =4.5 ÷ 15V IoL Current Limit Vi =4.5 ÷ 15V 2.5 Iq Quiescent Current Vi =12V Io = 0A 1.8 2.5 mA fs Switching Frequency Vi =12V Io = 1.5A 250 275 kHz SRV mV/°C 0 225 1.5 Supply Voltage Rejection A A mV/V Vr Ripple Voltage Vi =12V Io = 1A/1.5A Rth Thermal Resistance Case to ambient 25/35 mVpp °C/W USER NOTES Input Voltage The recommended operating maximum DC Input Voltage is 15V inclusive of ripple voltage. Current protection The device has two current limit protections, pulse by pulse and frequency fold back. The current is sensed through a resistor and if reaches the threshold, the on time is reduced and consequently the output voltage too. Since the minimum switch ON time (necessary to avoid false overcurrent signal) is not enough to obtain a sufficiently low duty cycle at 250 Hz, the output current, in strong overcurrent or short circuit conditions, could increase again. For this reason the switching frequency is also reduced, so keeping the inductor current under its maximum threshold. The frequency depends on the feedback voltage. As the feedback voltage decreases (due to the reduced duty cycle), the switching frequency decrease too. Thermal shutdown The shutdown block generates a signal that turns off the power stage if the temperature of the internal chip goes higher than a fixed internal threshold (150 ºC). The sensing element of the chip is very close to the PDMOS area, so ensuring an accurate and fast temperature 3/5 GS-R12VXXX1.5 detection. An hysteresis of approximately 20ºC avoids that the devices turns on and off continuously. Thermal Characteristics ADDITIONAL FEATURES AND PROTECTIONS Feedback disconnection In case of feedback disconnection, the duty cycle increases versus the maximum allowed value, bringing the output voltage close to the input supply. THis condition could destroy the load. To avoid this dangerous condition, the device is turned off if the internal feedback pin remains floating. Output overvoltage protection The overvoltage protection, OVP, is realized by using an internal comparator, which input is connected to the feedback, that turns off the power stage when the OVP threshold is reached. This threshold is typically 30% higher than the feedback voltage. 4/5 GS-R12VXXX1.5 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners © 2003 STMicroelectronics - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Belgium - Brazil - Canada -China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com 5/5