G914 Global Mixed-mode Technology Inc. 150mA Low-Dropout Linear Regulators Features General Description The G914 is a low supply current, low dropout linear regulator that comes in a space saving SOT23-5 package. The supply current at no-load is 52µA. In the shutdown mode, the maximum supply current is less than 1µA. Operating voltage range of the G914 is from 2.5V to 5.5V. The over-current protection limit is set at 370mA typical and 150mA minimum. An overtemperature protection circuit is built-in in the G914 to prevent thermal overload. These power saving features make the G914 ideal for use in the battery-powered applications such as notebook computers, cellular phones, and PDA’s. Low, 52µA Ground Current Guaranteed 150mA Output Current Dropout Voltage is 100mV @ 50mA Load Over-Temperature Protection and Short-Circuit Protection Adjustable Mode: from 2.5V to 5.5V Max. Supply Current in Shutdown Mode < 1µA Low Output Noise is 170 µVRMS Applications Notebook Computers Cellular Phones PDAs Digital still Camera and Video Recorders Hand-Held Devices Bar Code Scanners The G914 is a adjustable output version in a small SOT 23-5 package. Ordering Information TEMP. RANGE PINPACKAGE -40°C~ +85°C SOT 23-5 PART MARKING VOLTAGE G914 14 Adjustable Pin Configuration IN 1 5 OUTPUT VOLTAGE OUT IN OUT R1 ＋ G914 ADJ GND 2 － G914 BATTERY C IN 1µF SHDN GND COUT 1µF R2 470pF SHDN 3 4 ADJ Adjustable mode SOT23-5 VOUT =1.250 X ( R2/R1+1) TEL: 886-3-5788833 http://www.gmt.com.tw Ver 0.1 Preliminary Nov 05, 2001 1 G914 Global Mixed-mode Technology Inc. Continuous Power Dissipation (TA = +25°C) SOT23-5……………………………………...…..568 mW Operating Temperature Range………...-40°C to +85°C Junction Temperature……………………….……+150°C θJA….…..……………….…………….…..…..220°C/Watt Storage Temperature Range………….-65°C to +160°C Lead Temperature (soldering, 10sec)..…………+300°C Absolute Maximum Ratings VIN to GND……………………………………-0.3V to +7V Output Short-Circuit Duration………………….….Infinite SET to GND.……………………………..…..-0.3V to +7V SHDN to GND…………………..………….-0.3V to +7V SHDN to IN….…………………..…………..-7V to +0.3V OUT to GND…………………………-0.3V to (VIN + 0.3V) Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Electrical Characteristics (VIN = VOUT +1V; V SHDN = VIN; CIN = COUT = 1µF = TA = TJ = +25°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Voltage (Note 2) Output Voltage Accuracy Adjustable Output Voltage Range (Note 3) Maximum Output Current Current Limit VIN VOUT VOUT Dropout Voltage (Note 3) VDROP Line Regulation ∆VLNR VOUT = 0V ILOAD = 0mA ILOAD = 150mA IOUT = 1mA IOUT = 50mA IOUT =150mA VIN=VO +0.1V to 5.5V, IOUT = 1mA Load Regulation ∆VLDR IOUT = 0mA to 150mA Ground Pin Current Output Voltage Temperature Coefficient Output Voltage Noise (10HZ to 100KHZ) ILIM Variation from specified VOUT, IOUT=1mA IQ Note2 -2 2.5 150 52 %/V mV 40 ppm/°C CADJ = 10nF 170 TA = +25°C µA 30 192 VIH VIL 80 2 100 340 0.1 CADJ = 470pF IL = 150mA V % V mA mA 370 ∆VO / ∆T IOUT = 40mA, TJ = 25°C to 125°C en 5.5 2 5.5 mV µVRMS SHUTDOWN SHDN Input Bias Current I SHDN Regulator enabled Regulator shutdown V SHDN = VIN 0.007 0.1 µA Shutdown Supply Current ADJ INPUT ADJ Input Leakage Current THERMAL PROTECTION Thermal Shutdown Temperature Thermal Shutdown Hysteresis IQSHDN VOUT = 0V TA = +25°C 0.06 1 µA VADJ = 1.3V TA = +25°C 5 20 nA SHDN Input Threshold IADJ TSHDN ∆TSHDN 2 0.4 150 15 V °C °C Note 1: Limits is 100% production tested at TA= +25°C. Low duty pulse techniques are used during test to maintain junction temperature as close to ambient as possible. Note 2: VIN (min) = VOUT +VDROP. Note 3: The dropout voltage is defined as (VIN-VOUT) when VOUT is 100mV below the value of VOUT for VIN = VOUT +2V. TEL: 886-3-5788833 http://www.gmt.com.tw Ver 0.1 Preliminary Nov 05, 2001 2 Global Mixed-mode Technology Inc. G914 Pin Description PIN NAME FUNCTION 1 IN 2 GND 3 SHDN 4 ADJ 5 OUT Regulator Input. Supply voltage can range from +2.5V to +5.5V. Bypass with 1µF to GND Ground. This pin also functions as a heatsink. Solder to large pads or the circuit board ground plane to maximize thermal dissipation. Active-Low Shutdown Input. A logic low reduces the supply current to less than 1µA. Connect to IN for normal operation. Adjust (Input): Adjustable regulator feedback input. It can connect to an external resistor divider for adjustable output voltage. It also must connect ≥470pF ceramic capacitor from ADJ pin to GND for reduce output noise. Regulator Output. Fixed or adjustable from +2.5V to +5.5V. Sources up to 150mA. Bypass with a 1µF, ＜0.2Ω typical ESR capacitor to GND. Detailed Description This equation is correct due to the configuration of the bandgap reference. The bandgap voltage is relative to the output, as seen in the block diagram. Traditional regulators normally have the reference voltage relative to ground and have a different VOUT equation. Resistor values are not critical because ADJ (adjust)has a high input impedance, but for best results use resistors of 470kΩ or less. A capacitor from ADJ to ground provides greatly improved noise performance. The block diagram of the G914 is shown in Figure 1. It consists of an error amplifier, 1.25V bandgap reference, PMOS output transistor, shutdown logic, over current protection circuit, and over temperature protection circuit. The G914 can be adjusted to a specific output voltage by using two external resistors (Figure 2). The resistors set the output voltage based on the following equation: R2 VOUT =1.250V X +1 R1 IN SHDN SHUTDOWN LOGIC ERROR AMP. ＋ OVER TEMP. & OVER CURRENT PROTECTION OUT 1.25V ref ADJ GND Figure 1. Functional Diagram TEL: 886-3-5788833 http://www.gmt.com.tw Ver 0.1 Preliminary Nov 05, 2001 3 G914 Global Mixed-mode Technology Inc. OUT IN of the chosen package to the ambient air. In the case of a SOT23-5 package, the thermal resistance is typically 220oC/Watt. OUTPUT VOLTAGE R1 ＋ The die attachment area of the G914’s lead frame is connected to pin 2, which is the GND pin. Therefore, the GND pin of G914 can carry away the heat of the G914 die very effectively. To improve the power dissipation, connect the GND pin to ground using a large ground plane near the GND pin. G914 ADJ － BATTERY CIN 1µF SHDN GND COUT 1µF R2 RL 470pF Applications Information Figure 2. Adjustable Output Using External Feedback Resistors Capacitor Selection and Regulator Stability Normally, use a 1µF capacitor on the input and a 1µF capacitor on the output of the G914. Larger input capacitor values and lower ESR provide better supply-noise rejection and transient response. A highervalue input capacitor (10µF) may be necessary if large, fast transients are anticipated and the device is located several inches from the power source. Over Current Protection The G914 use a current mirror to monitor the output current. A small portion of the PMOS output transistor’s current is mirrored onto a resistor such that the voltage across this resistor is proportional to the output current. This voltage is compared against the reference voltage. Once the output current exceeds the limit, the PMOS output transistor enters constant current mode. The current is set to 370mA typically. Power-Supply Rejection and Operation from Sources Other than Batteries The G914 is designed to deliver low dropout voltages and low quiescent currents in battery powered systems. Power-supply rejection is 42dB at low frequencies. Over Temperature Protection To prevent abnormal temperature from occurring, the G914 has a built-in temperature monitoring circuit. When it detects the temperature is above 150oC, the output transistor is turned off. When the IC is cooled down to below 135oC, the output is turned on again. In this way, the G914 will be protected against abnormal junction temperature during operation. When operating from sources other than batteries, improve supply-noise rejection and transient response by increasing the values of the input and output capacitors, and using passive filtering techniques. Load Transient Considerations The G914 load-transient response graphs show two components of the output response: a DC shift of the output voltage due to the different load currents, and the transient response. Typical overshoot for step changes in the load current from 0mA to 100mA is 12mV. Increasing the output capacitor's value and decreasing its ESR attenuates transient spikes. Shutdown Mode When the SHDN pin is connected a logic low voltage, the G914 enters shutdown mode. All the analog circuits are turned off completely, which reduces the current consumption to only the leakage current. The output is disconnected from the input. When the output has no load at all, the output voltage will be discharged to ground through the internal resistor voltage divider. Input-Output (Dropout) Voltage A regulator's minimum input-output voltage differential (or dropout voltage) determines the lowest usable supply voltage. In battery-powered systems, this will determine the useful end-of-life battery voltage. Because the G914 use a P-channel MOSFET pass transistor, their dropout voltage is a function of RDS(ON) multiplied by the load current. Operating Region and Power Dissipation Since the G914 is a linear regulator, its power dissipation is always given by P = IOUT (VIN – VOUT). The maximum power dissipation is given by: PD(MAX) = (TJ–TA)/θJA,=150oC-25oC/220oC/W= 568mW Where (TJ–TA) is the temperature difference the G914 die and the ambient air,θJA, is the thermal resistance TEL: 886-3-5788833 http://www.gmt.com.tw Ver 0.1 Preliminary Nov 05, 2001 4 Global Mixed-mode Technology Inc. Layout Guide An input capacitance of ≅ 1µF is required between the G914 input pin and ground (the amount of the capacitance may be increased without limit), This capacitor must be located a distance of not more than 1cm from the input and return to a clean analog ground. G914 routing wire. Otherwise, the actual voltage at the IN pin may exceed the absolute maximum rating. The output capacitor also must be located a distance of not more than 1cm from output to a clean analog ground. Because it can filter out the output spike caused by the surge current due to the inductive effect of the package pin and the printed circuit board’s routing wire. Figure 3 is suggested PCB layout of G914. Input capacitor can filter out the input voltage spike caused by the surge current due to the inductive effect of the package pin and the printed circuit board’s Figure 3. Suggested PCB Layout *Distance between pin & capacitor must no more than 1cm TEL: 886-3-5788833 http://www.gmt.com.tw Ver 0.1 Preliminary Nov 05, 2001 5 G914 Global Mixed-mode Technology Inc. Package Information C D L E H θ1 e1 e A A2 A1 b Note: 1. Package body sizes exclude mold flash protrusions or gate burrs 2. Tolerance ±0.1000 mm (4mil) unless otherwise specified 3. Coplanarity: 0.1000mm 4. Dimension L is measured in gage plane SYMBOLS DIMENSIONS IN MILLIMETERS NOM MIN A A1 A2 b C D E e e1 H L θ1 1.00 0.00 0.70 0.35 0.10 2.70 1.40 --------2.60 0.37 1º 1.10 ----0.80 0.40 0.15 2.90 1.60 1.90(TYP) 0.95 2.80 -----5º MAX 1.30 0.10 0.90 0.50 0.25 3.10 1.80 --------3.00 ----9º Taping Specification Feed Direction SOT23-5 Package Orientation TEL: 886-3-5788833 http://www.gmt.com.tw Ver 0.1 Preliminary Nov 05, 2001 6