up0111 Conceptual 600mA Low Dropout Linear Regulator General Description Pin Configuration Applications Ordering Information Features

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1 The is a compact fast response low dropout regulator specifically designed to continuously deliver up to 600mA output current. Designed with a P-channel MSFET series pass transistor, the yields extremely low dropout voltage (e.g. 00m at 600mA) and maintains very low ground current (70uA). The does not require a bypass capacitor, hence achieving the smallest PCB area. The is designed and optimized to work with low-value, low-cost ceramic capacitors. nly a uf ceramic output capacitor is required for stable operation for any load conditions. ther features include foldback overcurrent protection, quick soft start, and overtemperature protection. The is available in fixed output voltage from 0.8 to. with 0. per step or as an adjustable device with a 0.8 reference voltage. The device comes in various packages. Cellular and Cordless Phones Bluetooth Portable Radios and Accessaries Battery-Powered Equipment Laptop, Palmtops, Notebook Computers Hand-Held Instruments PCMCIA Cards Portable Information Appliances General Description 600mA Low Dropout Linear Regulator Applications Wide Input oltage Range from.5 to 5.5 Ultra Low Dropout oltage: 600mA Ultra Fast Response in Line/Load Transient Stable with uf Ceramic utput Capacitor Low Ground Current: 70uA Typical Low Shutdown Current: < ua Foldback utput Current Limit High utput Accuracy.5% Initial Accuracy Fixed utput oltages: 0.8 to. Adjustable utput oltage from 0.8 to 4.5 ver-temperature Protection RoHS Compliant and Halogen Free ST-L (AMA) Features Pin Configuration EN 5 4 ST-5L (AMA5) FB rdering Information ST-L (AJA) ST-L (BJA) rder Number AMA-XX AMA5-XX AJA-XX BJA-XX AKA-XX BKA-XX ADD8-XX ADC8-XX PSU8-XX QSU8-XX Package ST-L ST-5L ST-L ST-L ST89-L ST89-L DFNx-8L DFN6x5-8L PSP-8L PSP-8L Remark XX: oltage ptions 00: Adjustable utput oltage 08: 0.8; 0:.0; :. 5:.5; 8:.8; etc... D:.5; L:.4 (00 version is not available for -lead packages ) Note: upi products are compatible with the current IPC/ JEDEC J-STD-00 requirement. They are halogen-free, RoHS compliant and 00% matte tin (Sn) plating that are suitable for use in SnPb or Pb-free soldering processes. ST89-L (AKA) ST89-L (BKA) 8 EN NC 7 NC EN FB PSP-8L (PSU8) 8 EN 7 NC FB DFN x (ADD8) Note: The figures are not to scale 4 5 PSP-8L (QSU8) DFN 6x5 (ADC8) FB NC EN NC FB

2 Typical Application Circuit IN. C uf/00ma.uf/500ma AMA- C uf/00ma.uf/500ma IN =. 5 C uf/00ma.uf/500ma Enable Disable EN AMA FB R 00K R 00K C pf C uf/00ma.uf/500ma Pin No. Pin Name Pin Function G ND Ground. EN 4 FB 5 Functional Pin Description Input oltage. This pin connects to the source of the internal pass transistor that supplies current to the output pin. Bypass to with a minimum uf ceramic capacitor. Place the decoupling capacitor physically as close as possible to the device. Enable Input. Pulling this pin below 0.5 turns the regulator off, reducing the quiescent current to a fraction of its operating value. This pin is not available for -pin packages. Feedback Pin (Adjustable ersion). This pin is the non-inverting input of the error amplifier. The FB pin voltage is regulated to 0.8 reference voltage. Set the output voltage according to = 0.8 x (R + R)/ R (). This pin is not internally connected for the fixed output version. utput oltage. This pin is power output of the device. A pull low resistance exists when the device is disabled by pulling low the EN pin. To maintain adequate transient response to large load change, a minimum uf ceramic capacitor is required to reduce the effects of current transients on.

3 Functional Block Diagram Power n Reset Current Sense EN Band Gap Thermal Shutdown REF Error Amp. Fixed MSFET Driver Adjustable FB Definitions Some important terminologies for LD are specified below. Dropout oltage The input/output oltage differential at which the regulator output no longer maintains regulation against further reductions in input voltage. Measured when the output drops % below its nominal value, dropout voltage is affected by junction temperature, load current and minimum input supply requirements. Line Regulation The change in output voltage for a change in input voltage. The measurement is made under conditions of low dissipation or by using pulse techniques such that average chip temperature is not significantly affected. Load Regulation The change in output voltage for a change in load current at constant chip temperature. The measurement is made under conditions of low dissipation or by using pulse techniques such that average chip temperature is not significantly affected. Maximum Power Dissipation The maximum total device dissipation for which the regulator will operate within specifications. Functional Description Quiescent Bias Current Current which is used to operate the regulator chip and is not delivered to the load. The quiescent current I Q is defined as the supply current used by the regulator itself that does not pass into the load. It typically includes all bias currents required by the LD and any drive current for the pass transistor. The is a compact fast transient response low dropout regulator specifically designed to continuously deliver up to 600mA output current for space-limited applications. Designed with a P-channel MSFET series pass transistor, the yields extremely low dropout voltage (e.g. 00m at 600mA) and maintain very low ground current (70uA). The does not require a bypass capacitor, hence achieving the smallest PCB area. The is designed and optimized to work with lowvalue, low-cost ceramic capacitors. nly a uf ceramic output capacitor is required for stable operation for any load conditions. ther features include foldback overcurrent protection, quick soft start, and overtemperature protection. The is available in fixed output voltages from 0.8 to. with 0. increments. As shown in the Functional Block Diagram, the consists of a bandgap for reference voltage, error amplifier, P-channel MSFET pass transistor and internal feedback

4 connected to the inverting input of error amplifier. The error amplifier compares this reference voltage with the feedback voltage and amplifies the difference. If the feedback voltage is lower than the reference voltage, the pass-transistor gate is pulled low. This allows more current to pass to the output and increases the output voltage. If the feedback voltage is too high, the pass transistor gate is pulled high, allowing less current to pass to the output. The output voltage is fed back through an internal or external resistor voltage-divider connected to the pin. Additional blocks include a current limiter, thermal sensor, and shutdown logic. Supply Input Power n Reset The input voltage supplies current to the output voltage and supplies current for control circuit. The input voltage is monitored for power on reset (PR) to ensure the regulator is not enabled until the input voltage is high enough for normal operation. The PR threshold level is typical. at IN rising. Enable/Shutdown The features an active-high enable pin that allows the regulator to be disabled. Forcing the enable pin lower than 0.5 shuts down the regulator and reduces its quiescent current less than ua. The voltage reference, error amplifier, gate-driver circuit and pass transistor are disabled in the shutdown state. When the regulator is in shutdown mode, an internal 600Ω resistor is connected between and. This is intended to discharge C when the LD regulator is disabled. The internal 600Ω has no adverse effect on device turn-on time. Forcing the enable pin higher than. enables the output voltage (once the input voltage is higher than its PR threshold level). If the enable function is not needed in a specific application, it may be tied to to keep the regulator in an always on state. The enable pin uses CMS technology and cannot be left floating, as this may cause an indeterminate state on the output. Current Limit and Short-Circuit Protection The includes a current limiter that monitors and controls the gate voltage of pass transistor to limit the output current to 500mA typically. A short circuit protector monitors the output voltage and asserts output short circuit if is lower than 40% of NM. The current limiting level is reduced to 800mA. The output voltage is rebuilt after short circuit is removed. Functional Description vertemperature Protection The overtemperature protection limits total power dissipation in the. When the junction temperature exceeds T J = 70 C, the thermal sensor signal the shutdowns logic, turning off the pass transistor and allows the device to cool down. The thermal sensor turns on the pass transistor again after the device junction temperature drops by 40 C, resulting in a pulsed output during continuous during continuous thermal-overload conditions. The over temperature protection is designed to protect the device in the event of a fault condition. For continual operation, do not exceed the recommended temperature of T J = 5 C for maximum reliability. 4

5 Absolute Maximum Rating Supply Input oltage IN (Note ) -0. to +6 ther Pins -0. to ( IN + 0.) Storage Temperature Range -65 C to +50 C Junction Temperature - 50 C Lead Temperature (Soldering, 0 sec) 60 C ESD Rating (Note ) HBM (Human Body Mode) k MM (Machine Mode) 00 Thermal Information Package Thermal Resistance (Note ) ST-L θ JA - 50 C/W ST-5L θ JA - 50 C/W ST89-L θ JA - 5 C/W ST-L θ JA C/W DFNx-8L θ JA - 60 C/W DFN6x5-8L θ JA - 45 C/W PSP-8L θ JA 55 C/W ST-L θ JC 40 C/W ST-5L θ JC 40 C/W ST89-L θ JC 5 C/W ST-L θ JC C/W DFNx-8L θ JC 5 C/W DFN6x5-8L θ JC 4 C/W PSP-8L θ JC 5 C/W Power Dissipation, P T A = 5 C ST-L - 0.4W ST-5L - 0.4W ST89-L - 0.8W ST-L.6W DFNx-8L.8W DFN6x5-8L.W PSP-8L -.0W Recommended peration Conditions perating Junction Temperature Range (Note 4) -0 C to +5 C perating Ambient Temperature Range -0 C to +85 C Supply Input oltage, IN to

6 Electrical Characteristics Parameter Symbol Test Conditions Min Typ Max Unit Supply Input oltage Supply Input oltage PR Threshold RTH PR Hysteresis RHYS Quiescent Current I Q EN Shutdown Current IS HDN utput oltage IN. 5 P - P - EN = 5, I = 0mA 40 0 = ua - 0. ua utput oltage Accuracy IN = +.0; I = ma, NM fixed output voltage version % NM Reference Accuracy oltage FB IN =., I = ma, = FB adjustable output voltage version, utput Line Regulation Δ REF(LINE ) utput Load Regulation Δ REF(LAD).5 < I N I = ma ma < I < 5.5, and I N < 500mA, I N > +.0 = N M, %/ %/ A Dropout oltage RP Power Ratio Enable Supply Rejection I = 00mA,.5 < IN D I = 600mA,.7 < IN PSRR Frequency = 0Hz, Freequency = khz, Frequency = 00kHz, Frequency = 0Hz, Freequency = khz, Frequency = 00kHz, I I I I I <.7 - < = 0mA 68 = 0mA 65 = 0mA 50 = 00mA 48 I = 00mA 6 = 00mA 65 m db Enable Disable EN Input High Level Low Level Current EN. SD 0.5 I N E Enable Delay Time TDELA Y IN = 5.5, = 5.5 or 0 - ua EN form design >. to > 0% EN NM, by 0 us utput Ramp Up Time T SS from design = 0% to 90% of, NM by 40 us 6

7 Electrical Characteristics Parameter Symbol Test Conditions Min Typ Max Unit Protection Current Limit Threshold I LIM A Short Circuit Current 0. 6 A Thermal Shutdown Temperature Thermal Shutdown Hysteresis T SD I = 0mA, IN T I SDHYS = 0mA, I N = EN = EN = 5.5 -, - 70 C = C Note. Stresses listed as the above Absolute Maximum Ratings may cause permanent damage to the device. These are for stress ratings. 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 remain possibility to affect device reliability. Note. Devices are ESD sensitive. Handling precaution recommended. Note. θ JA is measured in the natural convection at T A = 5 C on a low effective thermal conductivity test board of JEDEC 5- thermal measurement standard. Note 4. The device is not guaranteed to function outside its operating conditions. 7

8 Typical peration Characteristics This page is intentionally left blank and will be updated later. 8

9 The is specially designed to provide low-noise, high PSRR output voltage without a bypassing capacitor on its reference voltage. However, input and output capacitor should be well considered for optimal performance. Input Capacitors The requires well-decoupled supply input for optimal performance. A minimum uf capacitor is required frominput-to-ground to provide stability. Input capacitors greater than uf offer superior input line transient response and will assist in maximizing the highest possible power supply ripple rejection ratio (PSRR). Ceramic, tantalum, or aluminum electrolytic capacitors may be selected for CIN. There is no specific capacitor ESR requirement for CIN. However, low-esr ceramic capacitors provide optimal performance at a minimum of space and are highly recommended due to their inherent capability over tantalum capacitors to withstand input current surges from low impedance sources such as batteries in portable devices. Additional high frequency capacitors, such as small-valued NP dielectric type capacitors, help filter out high-frequency noise and are good design practice in any RF-based circuit. Place the capacitors physically as close as possible to the device with wide and direct PCB traces. utput Capacitors and Stability For proper load voltage regulation and operational stability, a capacitor is required between and pins. The is designed and optimized to work with low-value, low-cost ceramic capacitors in space saving and performance consideration. Typical output capacitor values for maximum output current conditions range from uf to 0uF. Larger capacitors are recommended for applications expecting low output noise and optimum power supply ripple rejection characteristics. Place the capacitors physically as close as possible to the device with wide and direct PCB traces. X7R/X5R dielectric-type ceramic capacitors are recommended because of their temperature performance. X7R type capacitors loss capacitance by 5% over their operating temperature rand and are the most stable type of ceramic capacitors. Z5U or Y5 dielectric capacitors loss their capacitance by 50% and 60% respectively over their operating temperature ranges. If Y5 or Z5U capacitors are used as output capacitors, the capacitance must be much higher than that of X7R capacitors to ensure the same minimum capacitance over the operating temperature range. ESR of output capacitors should be well considered to ensure stable operation of the device. High ESR capacitors may cause high frequency oscillation. Figure shows the Application Information acceptable ESR range of output capacitor for stability. No Load Stability The is designed to maintain output voltage regulation and stability under operational no load conditions. This is important characteristic for CMS RAM keep-alive applications where the output current may drop to zero. 9

10 ST-L Package Information 0.60 MAX.90 BSC.00 REF REF.60 REF.90 REF.60 REF.80 BSC.60 BSC.90 BSC Recommended Solder Pad Layout MAX BSC ST-5L 0.60 MAX.00 REF.90 BSC.60 REF.60 REF 0.95 REF.60 REF.80 BSC.60 BSC 0.95 BSC Recommended Solder Pad Layout MAX BSC 0

11 ST - L Package Information. MAX 6.50 BSC.00 BSC.50 MAX 7.00 BSC MIN 6.0 REF 7.80 MAX.50 MAX.0 BSC.00 MAX.0 BSC Recommended Solder Pad Layout MAX MIN 4.60 BSC ST89 - L.00 MAX REF.00 MAX 0.70 MIN MAX.50 BSC.00 MAX Recommended Solder Pad Layout MAX BSC

12 0.76 REF.7 REF.85 REF Conceptual PSP - 8L BSC Package Information.9 BSC MIN.9 REF 6.5 REF 8.00 MIN.7 BSC Recommended Solder Pad Layout BSC MAX BSC Note.Package utline Unit Description: BSC: Basic. Represents theoretical exact dimension or dimension target MIN: Minimum dimension specified. MAX: Maximum dimension specified. REF: Reference. Represents dimension for reference use only. This value is not a device specification. TYP. Typical. Provided as a general value. This value is not a device specification..dimensions in Millimeters..Drawing not to scale. 4.These dimensions no not include mold flash or protrusions. Mold flash or protrusions shell not exceed 0.5mm.

13 Package Information DFNx - 8L BSC REF MAX BSC Recommended Solder Pitch and Dimensions Note.Package utline Unit Description: BSC: Basic. Represents theoretical exact dimension or dimension target MIN: Minimum dimension specified. MAX: Maximum dimension specified. REF: Reference. Represents dimension for reference use only. This value is not a device specification. TYP. Typical. Provided as a general value. This value is not a device specification..dimensions in Millimeters..Drawing not to scale. 4.These dimensions no not include mold flash or protrusions. Mold flash or protrusions shell not exceed 0.5mm.

14 DFN6x5-8L Package Information BSC REF MAX BSC Recommended Solder Pitch and Dimensions Note.Package utline Unit Description: BSC: Basic. Represents theoretical exact dimension or dimension target MIN: Minimum dimension specified. MAX: Maximum dimension specified. REF: Reference. Represents dimension for reference use only. This value is not a device specification. TYP. Typical. Provided as a general value. This value is not a device specification..dimensions in Millimeters..Drawing not to scale. 4.These dimensions no not include mold flash or protrusions. Mold flash or protrusions shell not exceed 0.5mm. 4