XC9509 TOREX | Alldatasheet
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September 30, 2003 Ver. 1 Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector !Input Voltage Range 2.4V ~ 6.0V " APPLICATIONS !Output Voltage Range DC/DC 0.9 ~ 4.0V ( ±2%) # HDD VR 0.9 ~ 4.0V ( ±2%) # CD-R / RW, DVD VD 0.9 ~ 5.0V ( ±2%) # PDAs, portable communication modem !Switching Frequency 300kHz, 600kHz, 1.2MHz # Cellular phones !Output Current DC/DC 600mA # Palmtop computers VR 200mA # Cameras, video recorders !Ultra Small Packages MSOP-10, USP-10 !Ceramic Capacitor Compatible " GENERAL DESCRIPTION " FEATURES Input Voltage Range : 2.4V ~ 6.0V Load Capacitors : Ceramic Capacitors Compatible (Low ESR Capacitors) VD Function : Sense internally either VDD, DCOUT, or VROUT. Nch Open Drain Output <DC/DC Converter> Output Voltage Range : 0.9 ~ 4.0V ( ±2%) Output Current : 600mA Controls : PWM Control Oscillation Frequency : 300kHz, 600kHz, 1.2MHz <Regulator> Output Voltage Range : 0.9 ~ 4.0V ( ±2%) Current Limit 300mA Dropout Voltage : 80mV @ IOUT=100mA (VOUT=2.8V) High Ripple Rejection 60dB @1kHz (VOUT=2.8V) " TYPICAL APPLICATION CIRCUIT " TYPICAL PERFORMANCE CHARACTERISTICS XC9509 Series PWM, PWM / PFM Automatic Switching External The XC9509 series consists of a step-down DC/DC converter and a high-speed LDO regulator connected in parallel with the DC/DC converter's output. A voltage detector is also built-in. Since the input for the LDO voltage regulator block comes from the input power supply, it is suited for use with various applications. The DC/DC converter block incorporates a P-Channel driver transistor and a synchronous N-Channel switching transistor. With an external coil, diode and two capacitors, the XC9509 can deliver output currents up to 600mA at efficiencies over 90%. The XC9509 is designed for use with small ceramic capacitors. A choice of three switching frequencies are available, 300 kHz, 600 kHz, and 1.2 MHz. Output voltage settings for the DC/DC and VR are set-up internally in range is of 0.9V to 5.0V (± 2.0%). The soft start time of the series is internally set to 5ms. With the built- in U.V.L.O. (Under Voltage Lock Out) function, the internal P-channel driver transistor is forced OFF when input voltage becomes 1.4 V or lower. The functions of the MODE pin can be selected via the external control pin to switch the DC/DC control mode and the disable pin to shut down either the DC/DC block or the regulator block. MSOP-10 (TOP VIEW) LX DCOUT VROUT MODE AGND PGND CE PVDD AVDD CL2 L CL1 SD ( ) 5 6 CIN2 VDOUT VROUT DCOUT Semiconductor Ltd. CIN1 XC9509Hxxxx 100 0.1 1 10 100 1000 DC/DC Output Current IDOUT (mA) Efficiency EFFI (%) PWM/PFM Switching Control PWM Control DC/DC Efficiency (DCOUT:2.2V, 1.2MHz) VIN=3.6V, Topr=25OC, L:4.7uH(CDRH4D28C) CIN:4.7uF(ceramic), CL1:10uF(ceramic), CL2: 1uF(ceramic) Data Sheet 1
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " PIN CONFIGURATION " PIN ASSIGNMENT " SELECTION GUIDE # Ordering Information XC9509 123456 The input for the voltage regulator block comes from VDD. Control Methods, the MODE pin, the VD Sense pin (See the chart below) Setting voltage and specifications of each DC/DC, VR, and VD (Based on the internal standard) Oscillation Frequency of DC/DC : 300kHz 600kHz 1.2MHz Package Type : MSOP-10 USP-10 Device Orientation : Embossed Tape : Standard Feed Embossed Tape : Reverse Feed % Control Methods, MODE Pins, and VD SENSE Pins * The XC9509A to F series' MODE pin switches either the regulator block or DC/DC block to stand-by mode. When the CE mode is off, every function except for the VD function enters into stand-by mode. (The MODE pin does not operate independently.) PWM Control PFM/PWM Auto Switch PWM Control VDD DCOUT VROUT DC/DC : OFF DC/DC : ON VDD DCOUT VROUT VDD DCOUT VROUT H K PWM, PFM/PWM Manual Switch XC9509 Series VD SENSE VR : OFF VR : ON SERIES XC9509 A L B C D E F PIN NUMBER FUNCTIONPIN NAME Power GroundPGND VROUT A D VR Output SwitchLX DCOUT DC/DC Output MODE CE PVDD VDOUT AVDD AGND Mode Switch Chip Enable Power Supply 1 VD Input Power Supply 2 Analog Ground DESIGNATOR DESCRIPTIONSYMBOL R L 4 3 C DC/DC CONTROL METHODS MODE PINS (H LEVEL) MODE PINS (L LEVEL) Semiconductor Ltd. PGND 1 CE 2 PVDD 3 AVDD 4 VDOUT 5 10 LX
9 DCOUT
8 VROUT
7 MODE
6 AGND
MSOP-10 (TOP VIEW ) USP-10 (TOP VIEW) PGND 1 CE 2 PVDD 3 AVDD 4 VDOUT 5 10 LX
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " PACKAGING INFORMATION %MSOP-10 %USP-10 " BLOCK DIAGRAM * Diodes shown in the above circuits are protective diodes. " ABSOLUTE MAXIMUM RATINGS Ta=25OC (*1) IOUT = Pd / (VIN - VOUT) when PC board mounting. (*2) Package power dissipation V VDOUT CE Pin Voltage MODE Pin Voltage USP-10 MSOP-10 MODE - 0.3 ~ VDD + 0.3 DCOUT - 0.3 ~ VDD + 0.3 V PVDD V CE - 0.3 ~ VDD + 0.3 SYMBOL RATINGS UNITS AVDD - 0.3 ~ 6.5 V - 55 ~ + 125 OC OC 120 (*2) Topr TstgStorage Temperature Range VDOUT Pin Voltage LX Pin Voltage Continuous Power Dissipation (*1) Operating Temperature Range VROUT Pin Voltage AVDD Pin Voltage PVDD Pin Voltage DCOUT Pin Voltage PARAMETER 350Pd XC9509 Series mW LX VROUT - 0.3 ~ VDD + 0.3 V - 40 ~ + 85 0.15+0.01 0.53+0.10 0~5O 3.00+0.10 3.00+0.10 4.90+0.10- 0.86+0.05 0.075+0.025 (0.5 )(0.2) 2.7+0.05 0.15 0.25+0.0 6(0.1) (1.50) 2.30 (0.5) 0.2+0.05 * Soldering fillet surface is not formed because the sides of the pins are not plated. Semiconductor Ltd. Vref with soft start PWM/PFM Controller Phase Compensation + Logic Buffer, Driv er Current Limit & Feedback Ramp Wav e Generator, OSC DCOUT AVD D U.V.L.O LX VR OU T AGN D Current Limit Vref MODE MODE CONTROL each circuit VD OU T PGND CE ON/OFF, CONTROL each circuit Vref PV DD SENSE (VDD or DCOUT or VROUT) Data Sheet 3
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " ELECTRICAL CHARACTERISTICS XC9509HxxCAx % Common Characteristics % DC/DC Converter (2.2V product) % Regulator (1.8V product) VMH IROUT=30mA IDOUT=30mA -40OC<Topr<85OC MODE 'H' Level Voltage 0.6 Connected to the external components, IDOUT=10mA 1IMH - 0.1 Connected to the external components, IDOUT=30mA V 3 IDD2 MODE 'L' Level Current µΑIML - 0.1 - MODE 'H' Level Current MODE 'L' Level Voltage VML VSS - 0.1 CONDITIONS µΑ - 0.25 V 0.1 µΑ Ta=25OC 0.1 Ta=25OC mA mV ppm /OC V 2 - 0.1 - 0.1 UNITS mA - 0.25 - VDD 0.1 1.2 - 3830 CE 'L' Level Voltage VCEL VSS 3VDD µΑ 1 V 3V1.40 2.5 µΑ - 6.0 1.78 Supply Current 2 - µΑ 1300 - µΑ 1 240 PARAMETER SYMBOL MIN. IDD1 VIN=CE=DCOUT=5.0V MAX. UNITS TEST CIRCUIT V 3 mA 2 mS VROUT=VSS VIN={VOUT(T) + 1.0} VDC + 0.5Vp-pAC IROUT=30mA, f=1kHz -6 0 2 0.5 - 5 3-- MAX. TYP. ±100 TEST CIRCUIT PFM Duty Ratio CONDITIONS Ω UNITS Connected to the external components, No Load DCOUT=VIN TEST CIRCUIT 2.156 2.200 2.244 V 3 MIN. TYP. MAX. Manimum Duty Ratio MINDUTY 4MAXDUTY 1.02Oscillation Frequency FOSC Maximum Duty Ratio DCOUT=0V PFMDUTY 3 1.20 1.38 MHz 100 - -- 4 RLXL LX SW 'High' On Resistance (note 3) RLXH - ΩDCOUT=0V, LX=VIN-0.05V 0.5 600 %Connected to the external components, IDOUT=100mA -9 0 -Efficiency (note 4) EFFI Temperature Characteristics ! Topr # VOUT Output Voltage ! VOUT TSS - PARAMETER SYMBOL MIN. Connected to the external components, CE=0V"VIN, IDOUT=1mA Latch Time (note 5) Tlat CONDITIONS %/V 2 Maximum Output Current IMAX2 200 Load Regulation ! VROUT Dropout Voltage 1 (note 6) Vdif 1 mV 2 15 50 mV 2 30 - -85 0.6 Current Limit Line Regulation ILIM2 Output Voltage VROUT(E) CE 'H' Level Current ICEH ! VOUT Soft Start Time Stand-by Current (note 1) ISTB CE 'H' Level Voltage VCEH VINInput Voltage Range VUVLOU.V.L.O. Voltage (note 2) Supply Current 1 XC9509 Series Ta=25OC TYP. VIN=CE=5.0V, DCOUT=0V V - 0.6 VIN=6.5V, CE=0V 1.00 2.4 ILIM1Current Limit PARAMETER Output Voltage SYMBOL DCOUT Maximum Output Current IMAX1 LX SW 'Low' On Resistance CE 'L' Level Current ICEL IDOUT=30mA -40 OC<Topr<85OC mS- ppm /OC Connected to the external components, VIN=CE=5.0V, Short DCOUT by 1Ω resistor 1.8001.764 1.836 1mA<IROUT<100mA IROUT=30mA IROUT=100mA -d B VROUT(T)+1V<VIN<6V VROUT=VROUT(E)x0.9 - - mA 300 -0.2 PSRR ! VOUT - ±100 IROUT=30mA ! VIN # VOUT Ripple Rejection Rate Dropout Voltage 2 Vdif 2 Short-Circuit Current ISHORT Temperature Characteristics ! Topr # VOUT Output Voltage Semiconductor Ltd. Data Sheet 4
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " ELECTRICAL CHARACTERISTICS (Continued) % Detector (2.7V product) Test Conditions : Unless otherwise stated; * VROUT(T) : Setting Output Voltage DC/DC : VIN=3.6V [@ DCOUT:2.2V] VD : VIN=6.0V VR : VIN = VROUT(T) + 1.0 (V) [When VROUT(T) < 1.4V, VIN =2.4V] note 1 : VD operates when in stand-by mode. note 2 : Including hysteresis operating voltage range. note 3 : On resistance = 0.05V / ILX note 4 : EFFI = { ( Output Voltage x Output Current ) / ( Input Voltage x Input Current) } x 100 note 5 : Time until it short-circuits DCOUT with GND through 1Ω of resistance from a state of operation and is set to DCOUT=0V from current limit pulse generating. note 6 : Vdif = (VIN1 (note 7) - VROUT1 (note 8 ) ) note 7 : VIN 1 = The input voltage when VROUT1 appears as input voltage is gradually decreased. note 8 : VROUT1 = A voltage equal to 98% of the output voltage whenever an amply stabilized IOUT {VROUT(T) + 1.0V} is input. Temperature Characteristics ! Topr # VDF 8--40OC<Topr<85OC ±100 - ppm /OC Output Voltage ! VDF % -58 2.646 2.754 Hysteresis Range VHYS 3 TEST CIRCUIT V 8Detect Voltage VDF 2.700 VDOUT=0.5VVD Output Current IVD 1 UNITS XC9509 Series CONDITIONS Ta=25OC PARAMETER SYMBOL TYP. MAX. MIN. -- m A 9 Semiconductor Ltd. Data Sheet 5
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " TEST CIRCUITS Circuit 1 Supply Current, Stand-by Current, Circuit 2 Output Voltage (VR), Load Stability, Dropout Voltage, CE Current, MODE Current CE Current (MODE Current) Circuit 3 Output Voltage (DC/DC) Oscillation Frequency, Circuit 4 Minimum Duty Cycle, Maximum Duty Cycle U.V.L.O. Voltage, Soft start Time, Latch Time, CE Voltage, (PFM Duty Cycle), (MODE Voltage) Circuit 5 Lx ON Resistance Circuit 6 Current Limit 1 (DC/DC) Circuit 7 Current Limit 2 (VR), Short Protection (VR) Circuit 8 Detect Voltage, Release Voltage Circuit 9 Detect Voltage, Release Voltage XC9509 Series FOSC 300kHz 600kHz 1.2MHz L 22uH 10uH 4.7uH Semiconductor Ltd. 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE CIN:1.0uF (ceramic) AA A DCOUT : VIN or GND MODE: VIN or GND CIN : 4.7uF (ceramic) V CL : 10uF (ceramic) V L 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE IDOUT V CE : VIN 200 Ω 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE CIN : 1.0uF (ceramic) V CE : VIN 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE CIN : 1.0uF (ceramic) CIN:1uF V CE : VSS 200k Ω 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE VD_SENSE (DCOUT or VROUT) V CIN:1uF V CE : VSS A 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE VD_SENSE (DCOUT or VROUT) V IROUT V 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE CIN : 4.7uF (ceramic) CE : VIN or GND MODE: VIN or GND CL:1.0uF(ceramic, VROUT>1.5V) 2.2uF(ceramic, VROUT<1.5V) CE : VIN MODE: VIN or GND CIN : 4.7uF (ceramic) 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE IDOUT L MODE : VIN or GNDCE : VIN V V A CIN : 4.7uF (ceramic) 5 6 PVDD CE VDOUT AGND LX DCOUT VROUT AVDD PGND MODE CL:1.0uF(ceramic) Data Sheet 6
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " TYPICAL APPLICATION CIRCUIT CIN : 4.7 µF (ceramic, TAIYO-YUDEN) CL1 : 10 µF (ceramic, TAIYO-YUDEN) CL2 : 1 µF (ceramic, TAIYO-YUDEN), VROUT>1.5V : 2.2µF (ceramic, TAIYO-YUDEN), VROUT<1.5V " OPERATIONAL EXPLANATION %DC/DC Converter < Reference Voltage Source > The reference voltage source provides the reference voltage to ensure stable output voltage of the DC/DC converter. < Ramp Wave Circuit > < Error Amplifier > < PWM/PFM > XC9509 Series L The XC9509 series consists of a synchronous step-down DC/DC converter, a high speed LDO voltage regulator, and a voltage detector. FOSC 4.7µH (CDRH4D28C, SUMIDA) 10µH (CDRH4D28C, SUMIDA) 22µH (CDRH4D28C, SUMIDA) 1.2MHz 600kHz 300kHz The error amplifier is designed to monitor output voltage. The amplifier compares the reference voltage with the feedback voltage divided by the internal split resistors. When a voltage lower than the reference voltage is fed back, the output voltage of the error amplifier increases. The gain and frequency characteristics of the error amplifier output are fixed internally to deliver an optimized signal to the mixer. The ramp wave circuit determines switching frequency. The frequency is fixed internally and can be selected from 300kHz, 600 kHz and 1.2 MHz. Clock pulses generated in this circuit are used to produce ramp waveforms needed for PWM operation, and to synchronize all the internal circuits. MSOP-10 (TOP VIEW) The series consists of a reference voltage source, ramp wave circuit, error amplifier, PWM comparator, phase compensation circuit, output using the error amplifier, the voltage of the internal voltage reference source with the feedback voltage from the VOUT pin through split resistors. Phase compensation is performed on the resulting error amplifier output, to input a signal to the PWM comparator to determine the turn-on time during PWM operation. The PWM comparator compares, in terms of voltage level, the signal from the error amplifier with the ramp wave from the ramp wave circuit, and delivers the resulting output to the buffer driver circuit to cause the Lx pin to output a switching duty cycle. This process is continuously performed to ensure stable output voltage. The current feedback circuit monitors the P-channel MOS driver transistor current for each switching operation, and modulates the error amplifier output signal to provide multiple feedback signals. This enables a stable feedback loop even when a low ESR capacitor, such as a ceramic capacitor, is used, ensuring stable output voltage. The PWM mode of the XC9509A to F series are controlled on a specified frequency from light loads through the heavy loads. Since the frequency is specified, the composition of a noise filter etc. becomes easy. However, the efficiency at the time of the light load may become low. The XC9509H to L series can switch in any timing between PWM control and PWM/PFM automatic switching control. The series can not control only PFM mode. If needed, the operation can be set on a specified frequency; therefore, the control of the noise etc. is possible and the high efficiency at the time of the light load during PFM control mode is possible. With the automatic PWM/PFM switching control function, the series ICs are automatically switched from PWM control to PFM control mode under light load conditions. If during light load conditions the coil current becomes discontinuous and on-time rate falls lower than 30%, the PFM circuit operates to output a pulse with 30% of a fixed on-time rate from the Lx pin. During PFM operation with this fixed on-time rate, pulses are generated at different frequencies according to conditions of the moment. This causes a reduction in the number of switching operations per unit of time, resulting in efficiency improvement under light load conditions. However, since pulse output frequency is not constant, consideration should be given if a noise filter or the like is needed. Necessary conditions for switching to PFM operation depend on input voltage, load current, coil value and other factors. Semiconductor Ltd. LX DCOUT VROUT MODE AGND PGND CE PVDD AVDD CL2 L CL1 SD ( ) 5 6 CIN2 VDOUT VROUT DCOUT CIN1 Data Sheet 7
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " OPERATIONAL EXPLANATION (Continued) < Synchronous / Non-synchronous > % Continuous Mode : Synchronous % Discontinuous Mode : Non-Synchronous < Current Limit > XC9509 Series The current limiter circuit of the XC9509 series monitors the current flowing through the P-channel MOS driver transistor connected to the Lx pin, and features a combination of the constant-current type current limit mode and the operation suspension mode. 1 When the driver current is greater than a specific level, the constant-current type current limit function operates to turn off the pulses from the Lx pin at any given timing. 2 When the driver transistor is turned off, the limiter circuit is then released from the current limit detection state. 3 At the next pulse, the driver transistor is turned on. However, the transistor is immediately turned off in the case of an over current state. 4 When the over current state is eliminated, the IC resumes its normal operation. The IC waits for the over current state to end by repeating the steps 1 through 3 . If an over current state continues for 8msec and the above three steps are repeatedly performed, the IC performs the function of latching the OFF state of the driver transistor, and goes into operation suspension mode. Once the IC is in suspension mode, operations can be resumed by either turning the IC off via the CE pin, or by restoring power to the VIN pin. The suspension mode does not mean a complete shutdown, but a state in which pulse output is suspended; therefore, the internal circuitry remains in operation. The constant-current type current limit of the XC9509 series can be set at 1.2A. The XC9509 series automatically switches synchronous / non synchronous according to the state of the DC/DC converter. In the series, highly efficient operation using the synchronous mode while the coil current is in a continuation state. The series enters non-synchronous operation when the built-in Nch switching transistor for synchronous operation is shutdown which happens when the load current becomes low and the operation changes to a discontinuous state. The IC can operate without an external schottky diode because the parasitic diode in the Nch switching transistor provides the circuit's step- down operation. However, since Vf of the parasitic diode is high 0.6V, the efficiency level during non-synchronous operation shows a slight decrease. Please use an external schottky diode if high efficiency is required during light load current. 0mA ILmin ILmax Coil Current LX Wav e Form ILmax 0mA Coil Current LX Wav e Form VIN CE LX DCOUT IDOUT Current Limit LEVEL Limit<8mS Restart VSS 0mA Limit>8mS * 1.2MHz, Typical Semiconductor Ltd. Data Sheet 8
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector " OPERATIONAL EXPLANATION (Continued) < U.V.L.O. Circuit> %High Speed LDO Voltage Regulator < Reference Voltage Source > The reference voltage source provides the reference voltage to ensure stable output voltage of the regulator. < Error Amplifier > The error amplifier compares the reference voltage with the signal from VROUT, and the amplifier controls the output of the Pch driver transistor. <Current Limit Circuit> %Voltage Detector The detector block of the XC9509 series detects output voltage from the VDOUT pin while sensing either VDD, DCOUT, or VROUT internally. (N channel Open Drain Type) <CE Pin Function> <MODE Pin Function> XC9509 Series The operation of the XC9509 series' DC/DC converter block and voltage regulator block will enter into the shut down mode when a low level signal is input to the CE pin. During the shut down mode, the current consumption occurs only in the detector and is 0.6 µA (TYP.), with a state of high impedance at the Lx pin and the DCOUT pin. The IC starts its operation by inputting a high level signal to the CE pin. The input to the CE pin is a CMOS input and the sink current is 0 µA (TYP.). The operation of the XC9509A series' voltage detector block will enter into stand-by mode when a high level signal is input to the MODE pin. When a low level signal is input, the voltage regulator block will enter into stand-by mode. However, if the IC enters into stand-by mode via the CE pin, the voltage regulator block also shuts down. Likewise, if the XC9509B series enters into stand-by mode via the CE pin, the DC/DC converter block can also shut down. With the XC9509C series control can be PWM control when the MODE pin is 'H' level and PWM/PFM automatic switching control when the MODE pin is 'L' level. When the VIN pin voltage becomes 1.4 V or lower, the P-channel output driver transistor is forced OFF to prevent false pulse output caused by unstable operation of the internal circuitry. When the VIN pin voltage becomes 1.8 V or higher, switching operation takes place. By releasing causes pulse output to be suspended; therefore, the internal circuitry remains in operation. The voltage regulator block includes a combination of a constant current limiter circuit and a foldback circuit. The voltage regulator senses output current of the built-in P channel output driver transistor inside. When the load current reaches the current limit level, the current limiter circuit operates and the output voltage of the voltage regulator block drops. As a result of this drop in output voltage, the foldback circuit operates, output voltage drops further and the load current decreases. When the VROUT and GND pin are shorted, the load current of about 30mA flows. The voltage regulator block of the XC9509 series consists of a reference voltage source, error amplifier, and current limiter circuit. The voltage divided by split resistors is compared with the internal reference voltage by the error amplifier. The P-Channel MOSFET, which is connected to the VROUT pin, is then driven by the subsequent output signal. The output voltage at the VROUT pin is controlled and stabilized by a system of negative feedback. A stable output voltage is achievable even if used with low ESR capacitors as a phase compensation circuit is built-in. Semiconductor Ltd. Data Sheet 9