ISSUED DATE :2004/11/05 REVISED DATE :2006/04/18B GL2138 1 . 5 A C M O S L o w D ro p o u t Vo l t ag e R e g u l a t o r Description The GL2138 series of positive, linear regulators feature low quiescent current (45 A typ.) with low dropout voltage, making them ideal for battery applications. These rugged devices have both Thermal Shutdown, and Current Fold-back to prevent device failure under the “Worst” of operating conditions. The GL2138 is stable with an output capacitance of 4.7 F or greater. Features Very Low Dropout Voltage Guaranteed 1.5A output Over-Temperature Shutdown Current Limiting Short Circuit Current Fold-back Highly Accurate± 1.5% Low Temperature Coefficient Functional Block Diagram Applications Battery Powered Widgets Instrumentation Wireless Devices PC Peripherals Portable Electronics Package Dimensions SOT-223 REF. A C D E I H Millimeter Min. Max. 6.70 7.30 2.90 3.10 0.02 0.10 0° 10° 0.60 0.80 0.25 0.35 REF. B J 1 2 3 4 5 Millimeter Min. Max. 13°TYP. 2.30 REF. 6.30 6.70 6.30 6.70 3.30 3.70 3.30 3.70 1.40 1.80 Typical Application Circuit 1/5 ISSUED DATE :2004/11/05 REVISED DATE :2006/04/18B Absolute Maximum Ratings Parameter Symbol Ratings Unit Input Max Voltage VIN 8 V Output Current IOUT PD/( VIN- VO) A Output Voltage VOUT 1.5~5.0 V Operating Ambient Temperature Topr -40 ~ +85 Tj -40 ~ +125 Tj Max 150 Junction Temperature Maximum Junction Temperature Thermal Resistance jc (Non-Conductive Epoxy)* 31 /W ja 135 /W PD 800 mW Internal Power Dissipation EDS Classification B *Measure jc on backside center of tab. Electrical Characteristics VIN=VOUT(T)+2V, Ta=25 Parameter Output Voltage Symbol VOUT (E) Output Current Current Limit Load Regulation IO ILIM REGLOAD Dropout Voltage VDROPOUT unless otherwise noted Condition Min IQ IGND Line Regulation REGLINE Input Voltage Over Temperature Shutdown Over Temperature Hysterisis Output Voltage Temperature Coefficient Short Circuit Current 1.5% V - A -1.5% VO>1.2V 1.5 VO>1.2V 1.5 2.0 - A VIN=VOUT(T)+2V, IO=1mA to 1.5A -1 0.2 1 % 1.4V<VOUT(T) 2.0V - - 1300 2.0V<VOUT(T) 2.8V - - 800 2.8V<VOUT(T) - - 600 IO=1.5A VO=VOUT(E)-2% (Note2) - mV VIN= VOUT(T)+2V, IO=0mA - 45 70 A VIN= VOUT(T)+2V, IO=1mA~1.5A - 45 - A VOUT(T)<2.0V IO=1mA VIN=VOUT(T)+1 to 2.0V VOUT(T)<4.0V VOUT(T)+2 4.0V VOUT(T) -0.15 - 0.15 -0.1 0.02 0.1 -0.4 - 0.4 % Note3 - 7 - 150 - - 30 - TC - 30 - ppm/ - 750 70 50 20 30 - mA PSRR Output Voltage Noise Unit VIN OTS OTH ISC Power Supply Rejection Max IO=1mA (Note1) Quiescent Current Ground Pin Current TYP VOUT(T) eN VIN=VOUT(T)+1V, VOUT<0.4V f=100Hz f=1kHz f=10kHz f=10Hz~100kHz, Io=10mA, Co=4.7 F Io=100mA Co=4.7 F V dB Vrms Note 1: VOUT (E) =Effective Output Voltage (i.e. the output voltage when “VOUT (T) + 2.0V” is provided at the VIN pin while maintaining a certain IOUT value). 2: VOUT (T) =Specified Output Voltage 3: VIN (MIN) =V OUT+VDROPOUT Ordering Information ( contd. ) Part Number GL2138-15 GL2138-19 GL2138-33 GL2138-50 Marking 8T152 XXXX 8T192 XXXX 8T332 XXXX 8T502 XXXX Output Voltage 1.5V Part Number GL2138-18 1.9V GL2138-25 3.3V GL2138-47 Marking 8T182 XXXX 8T252 XXXX 8T472 XXXX Output Voltage 1.8V 2.5V 4.75V 5.0V 2/5 ISSUED DATE :2004/11/05 REVISED DATE :2006/04/18B Detailed Description The GL2138 series of COMS regulators contain a PMOS pass transistor, voltage reference, error amplifier, over-current protection, and thermal shutdown. The P-channel pass transistor receives data from the error amplifier, over-current shutdown, and thermal protection circuits. During normal operation, the error amplifier compares the output voltage to a precision reference. Over-current and Thermal shutdown circuits become active when the junction temperature exceeds 150 , or the current exceeds 2.2A. During thermal shutdown, the output voltage remains low. Normal operation is restored when the junction temperature drops below 120 . The GL2138 behaves like a current source when the load reaches 2.2A. However, if the load impedance drops below 0.3 , the current drops back to 600mA to prevent excessive power dissipation. Normal operation is restored when the load resistance exceeds 0.75 . External Capacitors The GL2138 is stable with an output capacitance to ground of 4.7 F or greater. Ceramic capacitors have the lowest ESR, and will offer the best AC performance. Conversely, Aluminum Electrolytic capacitors exhibit the highest ESR, resulting in the poorest AC response. Unfortunately, large value ceramic capacitors are comparatively expensive. One option is to parallel a 0.1 F ceramic capacitor with a 10 F Aluminum Electrolytic. The benefit is low ESR, high capacitance, and low overall cost. A second capacitor is recommended between the input and ground to stabilize Vin. The input capacitor should be at least 0.1 F to have a beneficial effect. All capacitors should be placed in close proximity to the pins. A “Quiet” ground termination is desirable. This can be achieved with a “Star” connection. Characteristics Curve 3/5 ISSUED DATE :2004/11/05 REVISED DATE :2006/04/18B 115 85 55 25 -5 -45 4/5 ISSUED DATE :2004/11/05 REVISED DATE :2006/04/18B Important Notice: All rights are reserved. Reproduction in whole or in part is prohibited without the prior written approval of GTM. GTM reserves the right to make changes to its products without notice. GTM semiconductor products are not warranted to be suitable for use in life-support Applications, or systems. GTM assumes no liability for any consequence of customer product design, infringement of patents, or application assistance. Head Office And Factory: Taiwan: No. 17-1 Tatung Rd. Fu Kou Hsin-Chu Industrial Park, Hsin-Chu, Taiwan, R. O. C. TEL : 886-3-597-7061 FAX : 886-3-597-9220, 597-0785 China: (201203) No.255, Jang-Jiang Tsai-Lueng RD. , Pu-Dung-Hsin District, Shang-Hai City, China TEL : 86-21-5895-7671 ~ 4 FAX : 86-21-38950165 5/5