Single, 1mA µcap ULDO General Description The is a high performance, single output ultra low LDO (ULDO ) regulator, offering low total output noise. The is capable of sourcing 1mA output current and offers high PSRR and low output noise, making it an ideal solution for RF applications. For battery operated applications, the offers 2% accuracy, extremely low dropout voltage (4mV @ 1mA), and low ground current (typically 8µA total). The can also be put into a zero-off-mode current state, drawing no current when disabled. The is available in the 1.6mm x 1.6mm Thin MLF package, occupying only 2.6mm 2 of PCB area, a 36% reduction in board area compared to SC-7 and 2mm x 2mm MLF packages. The has an operating junction temperature range of 4 C to +12 C and is available in fixed and adjustable output voltages in lead-free (RoHS compliant) Thin MLF and Thin SOT-23- packages. Data sheets and support documentation can be found on Micrel s web site at www.micrel.com. Features Ultra low dropout voltage 4mV @ 1mA Input voltage range: 2.3V to.v 1mA guaranteed output current Stable with ceramic output capacitors Ultra low output noise 3µVrms Low quiescent current 8µA total High PSRR up to 7dB@1kHz 3µs turn-on time High output accuracy ± 2% initial accuracy ± 3% over temperature Thermal shutdown and current limit protection Tiny 6-pin 1.6mm x 1.6mm Thin MLF leadless package Thin SOT-23- package Applications Mobile phones PDAs GPS receivers Portable electronics Digital still and video cameras Typical Application -x.xymt V IN VIN VOUT 1µF.1µF EN BYP 1µF Portable Application ULDO is a trademark of Micrel, Inc. MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc. Micrel Inc. 218 Fortune Drive San Jose, CA 9131 USA tel +1 (48) 944-8 fax + 1 (48) 474- http://www.micrel.com April 28 M9999-428
Ordering Information Part number Marking Code (1) Output Temperature Range Package Voltage (2) -2.8YML (4) 2JC 2.8V 4 C to +12 C 6-Pin 1.6mm x 1.6mm MLF YML (4) CAA ADJ. 4 C to +12 C 6-Pin 1.6mm x 1.6mm MLF -1.3YMT (3,4) 13C 1.3V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -1.YMT (3,4) 1C 1.V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -1.8YMT (3,4) 18C 1.8V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -2.1YMT (3,4) 21C 2.1V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -2.YMT (3,4) 2C 2.V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -2.6YMT (3,4) 26C 2.6V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -2.8YMT (3,4) 28C 2.8V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -2.8YMT (3,4) 2JC 2.8V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -2.9YMT (3,4) 29C 2.9V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -3.YMT (3,4) 3C 3.V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -3.3YMT (3,4) 33C 3.3V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -4.6YMT (3,4) 46C 4.6V 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF YMT (3,4) CAA ADJ. 4 C to +12 C 6-Pin 1.6mm x 1.6mm Thin MLF -1.3YD QC13 1.3V 4 C to +12 C -Pin TSOT-23-1.YD QC1 1.V 4 C to +12 C -Pin TSOT-23-1.8YD QC18 1.8V 4 C to +12 C -Pin TSOT-23-2.1YD QC21 2.1V 4 C to +12 C -Pin TSOT-23-2.YD QC2 2.V 4 C to +12 C -Pin TSOT-23-2.6YD QC26 2.6V 4 C to +12 C -Pin TSOT-23-2.8YD QC28 2.8V 4 C to +12 C -Pin TSOT-23-2.8YD QC2J 2.8V 4 C to +12 C -Pin TSOT-23-2.9YD QC29 2.9V 4 C to +12 C -Pin TSOT-23-3.YD QC3 3.V 4 C to +12 C -Pin TSOT-23-3.3YD QC33 3.3V 4 C to +12 C -Pin TSOT-23-4.6YD QC46 4.6V 4 C to +12 C -Pin TSOT-23 YD QCAA ADJ. 4 C to +12 C -Pin TSOT-23 Notes: 1. Under bar / Over bar symbol may not be to scale. 2. Other Voltages available. Contact Micrel for details. 3. Thin MLF Pin 1 indicator =. 4. MLF Thin MLF are GREEN RoHS compliant packages. Lead Finish is NiPdAu. Mold compound is Halogen Free. April 28 2 M9999-428
Pin Configuration EN 1 6 BYP EN 1 6 BYP 2 NC 2 ADJ VIN 3 4 OUT VIN 3 4 OUT 6-Pin 1.6mm x 1.6mm Thin MLF (MT) Fixed (Top View) 6-Pin 1.6mm x 1.6mm Thin MLF (MT) Adjustable (Top View) EN VIN 3 2 1 EN VIN 3 2 1 4 BYP OUT 4 ADJ OUT TSOT-23- (D) Fixed (Top View) TSOT-23- (D) Adjustable (Top View) Pin Description Pin No. Thin MLF-6 Fixed Pin No. Thin MLF-6 Adj. Pin No. TSOT-23- Fixed Pin No. TSOT-23- Adj. Pin Name Pin Function 1 1 3 3 EN Enable Input. Active High. High = on, low = off. Do not leave floating. 2 2 2 2 Ground 3 3 1 1 VIN Supply Input. 4 4 OUT. NC No connection. 4 ADJ Adjust Input. Connect to external resistor voltage divider network. 6 6 4 BYP Reference Bypass: Connect external.1µf to for reduced Output Noise. May be left open. HS Pad HS Pad E PAD Exposed Heatsink Pad connected to ground internally. April 28 3 M9999-428
Absolute Maximum Ratings (1) Supply Voltage (V IN )...V to +6V Enable Input Voltage (V EN )...V to +6V Power Dissipation, Internally Limited (3) Lead Temperature (soldering, 3sec)...26 C Storage Temperature (T S )... 6 C to +1 C Operating Ratings (2) Supply Voltage (V IN )... +2.3V to +.V Enable Input Voltage (V EN )... V to V IN Junction Temperature (T J )... 4 C to +12 C Junction Thermal Resistance MLF-6 (θ JA )... C/W Thin MLF-6 (θ JA )... C/W TSOT-23- (θ JA )... 23 C/W Electrical Characteristics (4) V IN = V OUT + 1.V; C OUT = 1.µF; I OUT = µa; T J = 2 C, bold values indicate 4 C to +12 C, unless noted. Parameter Conditions Min Typ Max Units Accuracy Variation from nominal V OUT -2. +2. % Variation from nominal V OUT ; 4 C to +12 C -3. +3. % Line Regulation to.v; I OUT = µa.2.3.6 Load Regulation I OUT = µa to 1mA.1 2. % Dropout Voltage () I OUT = µa I OUT = ma I OUT = 1mA.1 2 4 7 mv mv mv Ground Pin Current I OUT = to 1mA 8 12 µa Ground Pin Current in V EN.2V.1 2 µa Shutdown Ripple Rejection f = 1kHz; C OUT = 1.µF; C BYP =.1µF f = 2kHz; C OUT = 1.µF; C BYP =.1µF 7 db db Current Limit V OUT = V 27 4 8 ma Noise C OUT = 1.µF; C BYP =.1µF; Hz to khz 3 µv RMS Enable Input Enable Input Voltage Logic Low.2 V Logic High 1 V Enable Input Current V IL.2V.1 1 µa V IH 1.V.1 1 µa Turn-on Time Turn-on Time C OUT = 1.µF; C BYP =.1µF 3 µs Notes: 1. Exceeding the absolute maximum rating may damage the device. 2. The device is not guaranteed to function outside its operating rating. 3. The maximum allowable power dissipation of any T A (ambient temperature) is P D(max) = (T J(max) T A ) / θ JA. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. 4. Specification for packaged product only.. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 2% below its nominal value measured at 1V differential. %/V %/V April 28 4 M9999-428
Functional Diagram VIN VOUT EN BYP V REF Quick- Start Error Amp LDO Thermal Shutdown Current Limit Block Diagram Fixed VIN VOUT EN BYP V REF Thermal Shutdown Quick- Start Error Amp LDO Current Limit ADJ Block Diagram Adjustable April 28 M9999-428
Typical Characteristics -9-8 -7-6 - -4-3 Power Supply Rejection Ratio µa ma 1mA -2 V IN = 3.8V - C BYP =.1µF.1 1 1, FREQUENCY (khz) 6 4 4 3 3 2 2 1 Dropout Voltage vs. Temperature V OUT = 2.8V TEMPERATURE ( C) 1mA ma ma 2mA 4 4 3 3 2 2 1 Dropout Voltage vs. Output Current 2 7 12 1 OUTPUT CURRENT (ma) 2.88 vs. Output Current 3. vs. Supply Voltage 3.4 vs. Temperature 2.87 2.86 2.8 2.84 2.83 2.82 2 7 12 1 OUTPUT CURRENT (ma) 2. 2. µa 1. 1.. 1mA 1 2 3 4 6 SUPPLY VOLTAGE (V) 3.2 3. 2.8 2.6 2.4 2.2 I OUT = µa TEMPERATURE ( C) 9 8 7 6 4 3 2 Ground Current vs. Output Current 2 7 12 1 OUTPUT CURRENT (ma) 9 88 86 84 82 8 78 76 74 72 7 Ground Current vs. Temperature µa 1mA TEMPERATURE ( C) 9 8 7 6 4 3 2 Ground Current vs. Supply Voltage 1mA µa 3. 3. 4. 4... SUPPLY VOLTAGE (V) 49 48 47 46 4 44 43 42 4 Current Limit vs. Input Voltage V EN = V IN 3. 3. 4. 4... INPUT VOLTAGE (V) 1.1 Output Noise Spectral Density.1 V IN = 4V C BYP =.1µF.1.1.1 1 1,, FREQUENCY (khz) April 28 6 M9999-428
Functional Characteristics Enable Turn-On Load Transient Enable (.V/div) (2mV/div) 1mA (1V/div) C BYP =.1µF Output Current (ma/div) ma Time (µs/div) Time (4µs/div) Line Transient V 4V Input Voltage (2V/div) C BYP =.1µF I OUT = ma (mv/div) Time (4µs/div) April 28 7 M9999-428
Applications Information Enable/Shutdown The comes with an active-high enable pin that allows the regulator to be disabled. Forcing the enable pin low disables the regulator and sends it into a zero off-mode-current state. In this state, current consumed by the regulator goes nearly to zero. Forcing the enable pin high enables the output voltage. The active-high enable pin uses CMOS technology and the enable pin cannot be left floating; a floating enable pin may cause an indeterminate state on the output. Input Capacitor The is a high-performance, high bandwidth device. Therefore, it requires a well-bypassed input supply for optimal performance. A 1µF capacitor is required from the input to ground to provide stability. Low-ESR ceramic capacitors provide optimal performance at a minimum of space. Additional highfrequency capacitors, such as small-valued NPO dielectric-type capacitors, help filter out highfrequency noise and are good practice in any RFbased circuit. Output Capacitor The requires an output capacitor of 1µF or greater to maintain stability. The design is optimized for use with low-esr ceramic chip capacitors. High ESR capacitors may cause high frequency oscillation. The output capacitor can be increased, but performance has been optimized for a 1µF ceramic output capacitor and does not improve significantly with larger capacitance. X7R/XR dielectric-type ceramic capacitors are recommended because of their temperature performance. X7R-type capacitors change capacitance by 1% over their operating temperature range and are the most stable type of ceramic capacitors. ZU and YV dielectric capacitors change value by as much as % and 6%, respectively, over their operating temperature ranges. To use a ceramic chip capacitor with YV dielectric, the value must be much higher than an X7R ceramic capacitor to ensure the same minimum capacitance over the equivalent operating temperature range. Bypass Capacitor A capacitor can be placed from the noise bypass pin to ground to reduce output voltage noise. The capacitor bypasses the internal reference. A.1µF capacitor is recommended for applications that require low-noise outputs. The bypass capacitor can be increased, further reducing noise and improving PSRR. Turn-on time increases slightly with respect to bypass capacitance. A unique, quick-start circuit allows the to drive a large capacitor on the bypass pin without significantly slowing turn-on time. Refer to the Typical Characteristics section for performance with different bypass capacitors. No-Load Stability Unlike many other voltage regulators, the will remain stable and in regulation with no load. This is especially important in CMOS RAM keep-alive applications. Adjustable Regulator Application Adjustable regulators use the ratio of two resistors to multiply the reference voltage to produce the desired output voltage. The can be adjusted from 1.2V to.v by using two external resistors (Figure 1). The resistors set the output voltage based on the following equation: R1 V + OUT = VREF 1 R2 V REF = 1.2V V IN 1µF YMT VIN VOUT EN ADJ R1 R2 Figure 1. Adjustable Voltage Output 1µF V OUT Thermal Considerations The is designed to provide 1mA of continuous current. Maximum ambient operating temperature can be calculated based on the output current and the voltage drop across the part. Given that the input voltage is.v, the output voltage is 2.8V and the output current = 1mA. The actual power dissipation of the regulator circuit can be determined using the equation: P D = (V IN V OUT ) I OUT + V IN I Because this device is CMOS and the ground current is typically <µa over the load range, the power dissipation contributed by the ground current is < 1% and can be ignored for this calculation. P D = (V 2.8V) 1mA P D =.33W April 28 8 M9999-428
To determine the maximum ambient operating temperature of the package, use the junction-toambient thermal resistance of the device and the following basic equation: P D(MAX) = T J(MAX) - T A T J(max) = 12 C, the maximum junction temperature of the die θ JA thermal resistance = C/W. The table below shows junction-to-ambient thermal resistance for the in the 6-pin 1.6mm x 1.6mm MLF package. Package 6-Pin 1.6x1.6 MLF 6-Pin 1.6x1.6 Thin MLF JA θ JA Recommended Minimum Footprint C/W C/W The maximum power dissipation must not be exceeded for proper operation. For example, when operating the -2.8YML at an input voltage of V and 1mA load with a minimum footprint layout, the maximum ambient operating temperature T A can be determined as follows:.33w = (12 C T A )/( C/W) T A =92 C Therefore, a 2.8V application with 1mA of output current can accept an ambient operating temperature of 92 C in a 1.6mm x 1.6mm MLF package. For a full discussion of heat sinking and thermal effects on voltage regulators, refer to the Regulator Thermals section of Micrel s Designing with Low-Dropout Voltage Regulators handbook. This information can be found on Micrel's website at: http://www.micrel.com/_pdf/other/ldobk_ds.pdf Thermal Resistance Substituting P D for P D(max) and solving for the ambient operating temperature will give the maximum operating conditions for the regulator circuit. The junction-to-ambient thermal resistance for the minimum footprint is C/W. April 28 9 M9999-428
Package Information 6-Pin 1.6mm x 1.6mm MLF (ML) 6-Pin 1.6mm x 1.6mm Thin MLF (MT) April 28 M9999-428
-Pin TSOT-23 (D) MICREL, INC. 218 FORTUNE DRIVE SAN JOSE, CA 9131 USA TEL +1 (48) 944-8 FAX +1 (48) 474- WEB http:/www.micrel.com The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. 26 Micrel, Inc. April 28 11 M9999-428