up mA Low Dropout Linear Regulator General Description Pin Configuration Applications Ordering Information Features

Transcription

1 The up777 is a compact fast response low dropout regulator specifically designed to continuously deliver up to 6mA output current. Designed with a P-channel MSFET series pass transistor, the up777 yields extremely low dropout voltage (e.g. mv at 6mA) and maintains very low ground current (7uA). The up777 does not require a bypass capacitor, hence achieving the smallest PCB area. The up777 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 up777 is available in fixed output voltage from.8v to.v with.v per step or as an adjustable device with a.8v 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 up777 6mA Low Dropout Linear Regulator Applications rdering Information Wide Input Voltage Range from.5v to 5.5V Ultra Low Dropout Voltage: 6mA Ultra Fast Response in Line/Load Transient Stable with uf Ceramic utput Capacitor Low Ground Current: 7uA Typical Low Shutdown Current: < ua Foldback utput Current Limit High utput Accuracy.5% Initial Accuracy Fixed utput Voltages:.8V to.v Adjustable utput Voltage from.8v to 4.5V ver-temperature Protection Features RoHS Compliant and % Lead (Pb)-Free ST- (M) Pin Configuration EN 5 4 ST-5 (M5) FB rder Number Package Remark ST- (J) ST- (JA) up777m-xx ST- up777m5-xx ST-5 up777j-xx ST- up777ja-xx ST- up777k-xx ST89- up777ka-xx ST89- up777d-xx DFNx-8 up777d8a-xx DFN6x5-8 XX: Voltage ptions : Adjustable utput Voltage 8:.8V; :.V; :.V 5:.5V; 8:.8V; etc... D:.5V; L:.4V ( version is not available for -lead packages ) ST89- (K) PSP-8 (U8) EN NC NC EN FB ST89- (KA) PSP-8 (U8A) FB NC up777u8-xx PSP-8 up777u8a-xx PSP-8 Note: upi products are compatible with the current IPC/ JEDEC J-STD- and RoHS requirements. They are % matte tin (Sn) plating and suitable for use in SnPb or Pbfree soldering processes. 4 DFN x (D) 8 EN 7 NC 6 5 FB 4 DFN 6x5 (D8A) Note: The figures are not to scale EN NC FB

2 Typical Application Circuit V IN V =.6V 5 Enable Disable C.uF EN up777m5-4 FB R K R K C pf C.uF Pin No. Pin Name Pin Function G ND Ground. EN 4 FB 5 Functional Pin Description Input Voltage. 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.5v 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 Version). This pin is the non-inverting input of the error amplifier. The FB pin voltage is regulated to.8v reference voltage. Set the output voltage according to V =.8 x (R + R)/ R (V). This pin is not internally connected for the fixed output version. utput Voltage. 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 V REF Error Amp. Fixed MSFET Driver Adjustable FB Definitions Some important terminologies for LD are specified below. Dropout Voltage The input/output Voltage 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 up777 is a compact fast transient response low dropout regulator specifically designed to continuously deliver up to 6mA output current for space-limited applications. Designed with a P-channel MSFET series pass transistor, the up777 yields extremely low dropout voltage (e.g. mv at 6mA) and maintain very low ground current (7uA). The up777 does not require a bypass capacitor, hence achieving the smallest PCB area. The up777 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 up777 is available in fixed output voltages from.8v to.v with.v increments. As shown in the Functional Block Diagram, the up777 consists of a bandgap for reference voltage, error amplifier, P-channel MSFET pass transistor and internal feedback voltage divider. The.8V bandgap reference voltage is

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 voltagedivider 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.v at V IN rising. Enable/Shutdown The up777 features an active-high enable pin that allows the regulator to be disabled. Forcing the enable pin lower than.5v 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 6Ω resistor is connected between and. This is intended to discharge C when the LD regulator is disabled. The internal 6Ω has no adverse effect on device turn-on time. Forcing the enable pin higher than.v 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 up777 includes a current limiter that monitors and controls the gate voltage of pass transistor to limit the output current to 5mA typically. A short circuit protector monitors the output voltage and asserts output short circuit if V is lower than 4% of V NM. The current limiting level is reduced to 8mA. The output voltage is rebuilt after short circuit is removed. vertemperature Protection Functional Description The overtemperature protection limits total power dissipation in the up777. When the junction temperature exceeds T J = 7 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 4 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 Voltage V IN (Note ) - -.V to +6V ther Pins -.V to (V IN +.V) Storage Temperature Range C to +5 C Junction Temperature 5 C Lead Temperature (Soldering, sec) 6 C ESD Rating (Note ) HBM (Human Body Mode) - kv MM (Machine Mode) - V Thermal Information Package Thermal Resistance (Note ) ST- θ JA - 5 C/W ST-5 θ JA - 5 C/W ST89- θ JA - 5 C/W ST- θ JA 6.5 C/W DFNx-8 θ JA - 6 C/W DFN6x5-8 θ JA - 45 C/W PSP-8 θ JA 55 C/W ST- θ JC 4 C/W ST-5 θ JC 4 C/W ST89- θ JC 5 C/W ST- θ JC C/W DFNx-8 θ JC 5 C/W DFN6x5-8 θ JC - 4 C/W PSP-8 θ JC 5 C/W Power Dissipation, P T A = 5 C ST- -.4W ST-5 -.4W ST89-.8W ST- -.6W DFNx-8 -.8W DFN6x5-8.W PSP-8 -.W Recommended peration Conditions perating Junction Temperature Range (Note 4) - C to +5 C perating Ambient Temperature Range - C to +85 C Supply Input Voltage, V IN +.5V to +5.5V 5

6 Electrical Characteristics Parameter Symbol Test Conditions Min Typ Max Unit Supply Input Voltage Supply Input Voltage PR Threshold V RTH PR Hysteresis V RHYS Quiescent Current I Q V EN Shutdown Current IS HDN utput Voltage V IN. 5 P - P - V EN = 5V, I = ma 4 = V V -. V -. 4 V 7 5 ua -. ua utput Voltage Accuracy V V IN = V +.V; I = ma, NM fixed output voltage version V % NM Reference Accuracy Voltage V FB V IN =.V, I = ma, = FB adjustable output voltage version, V utput Line Regulation V REF(LINE ) utput Load Regulation V REF(LAD).5V < VI N I = ma ma < I < 5.5V, and VI N < 5mA, VI N > V +.V = VN M, +.V -.. %/ V %/ A Dropout Voltage V RP Power Ratio Enable Supply Rejection I = ma,.5v < V IN D I = 6mA,.7V < V IN PSRR Frequency = Hz, Freequency = khz, Frequency = khz, Frequency = Hz, Freequency = khz, Frequency = khz, I I I I I <.7V - < 5.5V = ma 68 = ma 65 = ma 5 = ma 48 I = ma 6 = ma 65 mv db Enable Disable EN Input High Level Low Level Current V EN. V V SD.5 V I N E Enable Delay Time TDELA Y V IN = 5.5V, V = 5.5V or V - ua EN form V design >.V to V > % V EN NM, by us utput Ramp Up Time T SS from V design = % to 9% of V, NM by 4 us 6

7 Electrical Characteristics Parameter Symbol Test Conditions Min Typ Max Unit Protection Current Limit Threshold I LIM. 9. A Short Circuit Current. 6 A Thermal Shutdown Temperature Thermal Shutdown Hysteresis T SD T SDHYS I I = ma, VI N = ma, VI N = VEN = VEN = 5.5V -, - 7 C = 5.5V 4 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 Power n Waveforms Typical peration Characteristics Turn n Waveforms V IN (V/Div) EN (V/Div) V (V/Div) V (V/Div) I IN (5mAV/Div) I IN (5mAV/Div) ms/div C IN = C = uf, V =.V, R = 5.5Ω Power ff Waveforms us/div C IN = C = uf, V =.V, R = 5.5Ω Turn ff Waveforms V IN (V/Div) V (V/Div) EN (V/Div) V (V/Div) I IN (5mAV/Div) I IN (5mAV/Div) ms/div C IN = C = uf, V =.V, R = 5.5Ω Load Transient Response us/div C IN = C = uf, V =.V, R = 5.5Ω Line Transient Response V IN (V/Div) V (5mV/Div) V (5mV/Div) I IN (5mAV/Div) us/div C IN = C = uf, V =.V, I = to 6mA 5us/Div C IN = C = uf, V =.V, V IN = 4V to 5V 8

9 Typical peration Characteristics utput Voltage Variation (%) utput Voltage vs. Temperature Temperature ( C) Shutdown Current (ua) Shutdown Current vs. Temperature Temperature ( C) Quiescent Current (ua) Quiscent Current vs. Temperature Temperature ( C) Enable/Disable Threshold (V) Enable/Disable vs. Temperature Temperature ( C) n Resistance (mω) n Resistance vs. Temperature Temperature ( C) V IN = V Pull Low Resistance (Ω) Pull Low Resistance vs. Input Voltage Input Voltage (V) EN = V, V = V, Pull Low Resistance at Pin. 9

10 Quiescent Current (ua) Dropout Current (mv) n Resistance (mω) Quiescent Current vs. Input Voltage Input Voltage (V) V =.8V Dropout Voltage vs. utput Current T J = 5 C utput Current (ma) V IN = V =.V T J = -5 C n Resistance vs. Input Voltage T J = 5 C Input Voltage I = 6mA utput Voltage Variation (%) Enable/Disable Threshold PSRR (db) Typical peration Characteristics utput Voltage Line Regulation Input Voltage (V) For V IN > V + V Enable/Disable vs. Input Voltage Enable Disable Input Voltage (V) PSRR 9 k k k M Frequency (Hz) V IN =.V, V =.8V, I = ma

11 The up777 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 up777 requires well-decoupled supply input for optimal performance. A minimum uf capacitor is required from-input-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 up777 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 uf. 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 Y5V dielectric capacitors loss their capacitance by 5% and 6% respectively over their operating temperature ranges. If Y5V 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 acceptable ESR range of output capacitor for stability. Application Information No Load Stability The up777 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.

12 ST- Package Information.6 MAX.9 BSC. REF REF.6 REF.9 REF.6 REF.8 BSC.6 BSC.9 BSC Recommended Solder Pad Layout MAX BSC ST-5.6 MAX. REF.9 BSC.6 REF.6 REF.95 REF.6 REF.8 BSC.6 BSC.95 BSC Recommended Solder Pad Layout MAX BSC

13 ST - Package Information. MAX 6.5 BSC. BSC.5 MAX 7. BSC MIN 6. REF 7.8 MAX.5 MAX. BSC. MAX. BSC Recommended Solder Pad Layout MAX MIN 4.6 BSC. -. ST89 -. MAX REF. MAX.7 MIN MAX.5 BSC. MAX Recommended Solder Pad Layout MAX BSC

14 PSP - 8 Package Information.76 REF.7 REF.85 REF BSC.9 BSC MIN.9 REF 6.5 REF 8. MIN.7 BSC. -.5 Recommended Solder Pad Layout BSC MAX BSC 4

15 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.5mm. 5

16 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.5mm. 6