Advanced Monolithic Systems

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Rhoda Holmes
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1 Advanced Monolithic Systems FEATURES.,.,. and. ersions High Accuracy Output oltage Extremely Low Quiescent Current Low Dropout oltage Extremely Tight Load and Line Regulation ery Low Temperature Coefficient Current and Thermal Limiting Needs Minimum Capacitance (µf) for Stability Unregulated DC Positive Transients ADDITIONAL FEATURES (AMS9 ONLY). to 9 Programmable Output Error Flag Warning of oltage Output Dropout Logic Controlled Electronic Shutdown AMS9/AMS9 ma LOW DROPOUT OLTAGE REGULATOR APPLICATIONS Battery Powered Systems Portable Consumer Equipment Cordless Telephones Portable (Notebook) Computers Portable Instrumentation Radio Control Systems Automotive Electronics Avionics Low-Power oltage Reference RoHS compliant GENERAL DESCRIPTION The AMS9 and AMS9 are micropower voltage regulators ideally suited for use in battery-powered systems. These devices feature very low quiescent current (typ.µa), and very low dropout voltage (typ.m at light loads and m at ma) thus prolonging battery life. The quiescent current increases only slightly in dropout. The AMS9/AMS9 has positive transient protection up to and can survive unregulated input transient up to below ground. The AMS9 and AMS9 were designed to include a tight initial tolerance (typ..%), excellent load and line regulation (typ..%), and a very low output voltage temperature coefficient, making these devices useful as a low-power voltage reference. The AMS9 is offered in the -pin TO-9 package. AMS9 is available in -pin plastic SOIC and DIP packages and offers three major additional system features. An error flag output warns of a low output voltage, often due to failing batteries on input. The AMS9 also features the logic-compatible shutdown input which enables the regulator to be switched on and off. The AMS9 device may be pin-strapped for a.,.,. or. output, or programmed from. to 9 with an external pair of resistors. ORDERING INFORMATION PACKAGE TYPE OPERATING TO-9 LEAD PDIP LEAD SOIC TEMP. RANGE AMS9ACN-X AMS9ACP- AMS9ACS-X IND. AMS9CN-X AMS9CP-X AMS9CS-X IND X =.,.,. PIN CONNECTION L SOIC/ L PDIP OUTPUT SENSE SHUTDOWN FEEDBACK TAP GROUND Top iew OUTPUT TO-9 Bottom iew Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

2 AMS9/AMS9 ABSOLUTE MAXIMUM RATINGS (Note ) Input Supply oltage -. to OPERATING RATINGS (Note ) SHUTDOWN Input oltage, Max. Input Supply oltage Error Comparator Output Junction Temperature Range oltage,(note 9) (T J ) (Note ) FEEDBACK Input oltage -. to AMS9AC-XX, AMS9C-XX (Note 9) (Note ) AMS9AC-XX, AMS9C-XX - C to C Power Dissipation Internally Limited Junction Temperature C Storage Temperature - C to C Soldering Temperature ( sec) C ELECTRICAL CHARACTERISTICS at s =out, Ta= C, unless otherwise noted. Parameter. ersions (Note ) Output oltage Output oltage. ersions (Note ) Output oltage Output oltage. ersions (Note ) Output oltage Output oltage. ersions (Note ) Output oltage Output oltage All oltage Options Conditions (Note ) T J = C (Note ) - C T J C Full Operating Temperature Range µa I L ma T J T JMAX T J = C (Note ) - C T J C Full Operating Temperature Range µa I L ma T J T JMAX T J = C (Note ) - C T J C Full Operating Temperature Range µa I L ma T J T JMAX T J = C (Note ) - C T J C Full Operating Temperature Range µa I L ma T J T JMAX Output oltage Temperature Coefficient (Note ) (Note ) AMS9AC AMS9AC Min. Typ. Max AMS9C AMS9C Min. Typ. Max Units ppm/ C Line Regulation (Note ) in (Note ).... % Load Regulation (Note ) µa I L ma.... % Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

3 ELECTRICAL CHARACTERISTICS (Note ) (Continued) Dropout oltage (Note ) PARAMETER I L = µ A I L = ma CONDITIONS (Note ) AMS9AC AMS9AC Min. Typ. Max. AMS9/AMS9 AMS9C AMS9C Min. Typ. Max. Units Ground Current I L = µa µa I L = ma ma Current Limit out = ma Thermal Regulation (Note ).... %/W Output Noise, Hz to KHz C L = µf C L = µf C L =. µf (Bypass =. µf pins to (AMS9)) -Pin ersions only AMS9AC AMS9C Reference oltage Reference oltage Over Temperature (Note ).9... Feedback Pin Bias Current na m m µ rms µ rms µ rms Reference oltage Temperature Coefficient ( Note ) Feedback Pin Bias Current Temperature Coefficient Error Comparator ppm/ C.. na/ C Output Leakage Current = OH.. µa Output Low oltage in =. I OL = µa m Upper Threshold oltage (Note ) m Lower Threshold oltage (Note ) 9 9 m Hysteresis (Note ) m Shutdown Input Input logic oltage Shutdown Pin Input Current (Note ) Regulator Output Current in Shutdown (Note ) Low (Regulator ON) High (Regulator OFF) s =. s =.... (Note ) µa Note : Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which operation of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions, see the Electrical Characteristics tables. Note : Unless otherwise specified all limits guaranteed for IN = ( ONOM ), I L = µa and C L = µf for versions and.µf for and. versions. Limits appearing in boldface type apply over the entire junction temperature range for operation. Limits appearing in normal type apply for T A = T J = C Additional conditions for the -pin versions are FEEDBACK tied to TAP, OUTPUT tied to SENSE and SHUTDOWN.. Note : Guaranteed and % production tested. Note : Guaranteed but not % production tested. These limits are not used to calculate outgoing AQL levels. Note : Dropout voltage is defined as the input to output differential at which the output voltage drops m below its nominal value measured at differential. At very low values of programmed output voltage, the minimum input supply voltage of (. over temperature) must be taken into account. Note : Comparator thresholds are expressed in terms of a voltage differential at the feedback terminal below the nominal reference voltage measured at IN = ( ONOM ). To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = out/ref = (R R)/R. For example, at a programmed output voltage of, the error output is guaranteed to go low when the output drops by 9 m x /. = m. Thresholds remain constant as a percent of out as out is varied, with the dropout warning occurring at typically % below nominal,.% guaranteed. Note : ref out ( in - ),. in, µa I L ma, T J T JMAX. µa µa Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

4 AMS9/AMS9 Note : The junction-to-ambient thermal resistance are as follows: C/W and C/W for the TO-9 (N) package with. inch and. inch leads to the printed circuit board (PCB) respectively, C/W for the molded plastic DIP (P) and C/W for the molded plastic SO- (S). The above thermal resistances for the N, S and P packages apply when the package is soldered directly to the PCB. Note 9: May exceed input supply voltage. Note : When used in dual-supply systems where the output terminal sees loads returned to a negative supply, the output voltage should be diode-clamped to ground. Note : shutdown, in, out =, Feedback pin tied to TAP. Note : Output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range. Note : Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load or line regulation effects. Specifications are for a ma load pulse at IN = (.W pulse) for T = ms. Note : Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation. Note : Line regulation for the AMS9 is tested at C for I L = ma. For I L = µa and T J = C, line regulation is guaranteed by design to.%. See typical performance characteristics for line regulation versus temperature and load current. Note : All AMS9 devices have the nominal output voltage coded as the last two digits of the part number. In the AMS9 products, the.. and. versions are designated by the last two digits, but the version is denoted with no code of the part number. BLOCK DIAGRAM AND TYPICAL APPLICATIONS AMS9-XX AMS9-XX UNREGULATED DC UNREGULATED DC OUT I L ma - AMPLIFIER. REFERENCE OUTPUT GROUND OUT I L ma SEE APPLICATION HINTS FROM CMOS OR TTL SHUT- DOWN FEED- BACK m - -. REFERENCE AMPLIFIER OUTPUT SENSE TAP GROUND kω SEE APPLICATION HINTS TO CMOS OR TTL DETECTION COMPARATOR Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

5 AMS9/AMS9 TYPICAL PERFORMANCE CHARACTERISTICS GROUND CURRENT (ma). Quiescent Current.. LOAD CURRENT (ma) OUTPUT OLTAGE () Dropout Characteristics Input Current OUTPUT OUTPUT R L = kω R L = kω R L = Ω R L = 9 OLTAGE () OLTAGE () CURRENT (µa) CURRENT (ma) Input Current OUTPUT R L = Ω 9 9 OLTAGE () OUTPUT OLTAGE () Temperature Drift of Representative Units OUTPUT.% QUIESCENT CURRENT ( µa) Quiescent Current OUTPUT I L = ma I L = OLTAGE () QUIESCENT CURRENT ( µa) 9 Quiescent Current OUTPUT I L = µa IN = QUIESCENT CURRENT (ma) 9 Quiescent Current OUTPUT IN = I L = ma QUIESCENT CURRENT ( µa) Quiescent Current OUTPUT I L = ma OLTAGE () Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

6 AMS9/AMS9 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) Short Circuit Current Dropout oltage Dropout oltage SHORT CIRCUIT CURRENT ( ma) DROPOUT OLTAGE (m) I L = ma ~ I L = µa DROPOUT OLTAGE (m) T J = C µa ma ma ma OUTPUT CURRENT MINIMUM OPERATING OLTAGE () AMS9 Minimum Operating oltage BIAS CURRENT (na) - - AMS9 Feedback Bias Current T A = - C FEEDBACK OLTAGE () FEEDBACK CURRENT (µa) AMS9 Feedback Pin Current PIN DREN BY EXTERNAL SOURCE (REGULATOR RUN OPEN LOOP) T A = C T A = C. OUTPUT () AMS9 Error Comparator Output 9. OUT =. k RESISTOR TO EXTERNAL SUPPLY. k RESISTOR TO OUT HYSTERESIS SINK CURRENT (ma).. AMS9 Comparator Sink Current T A = C T A = C T A = - C OUTPUT OLTAGE CHANGE OLTAGE Line Transient Response m m - m ~ C L = µf I L = ma OUT = OLTAGE () OUTPUT LOW OLTAGE ().9 TIME (µs) Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

7 AMS9/AMS9 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) OUTPUT OLTAGE CHANGE (m) LOAD CURRENT Load Transient Response - - C L = µf ~ OUT = ma µa TIME (ms) OUTPUT OLTAGE CHANGE (m) LOAD CURRENT Load Transient Response - C L = µf - OUT = - ~ ma µa TIME (ms) OUTPUT OLTAGE () SHUTDOWN PIN OLTAGE () ~ - - AMS9 Enable Transient C L = µf C L = µf I L = ma IN = OUT = TIME (µs) OUPUT IMPEDANCE (Ω).... Output Impedance I O = ma I O = µa I O = ma OUT = C L = µf.. K K K FREQUENCY (Hz) M RIPPLE REJECTION (db) Ripple Rejection 9 I L = C L = µf I L = µa IN = OUT = I L = ma FREQUENCY (Hz) FREQUENCY (Hz) RIPPLE REJECTION (db) Ripple Rejection 9 I L = ma C L = µf IN = OUT = RIPPLE REJECTION (db) Ripple Rejection I L = ma I L = ma C L = µf IN = OUT = OLTAGE NOISE SPECTRAL DENSITY(m/ Hz) AMS9 Output Noise OUTPUT C L =. µf C L = µf I L = ma C L = µf.. µf BYPASS PIN TO. PIN FREQUENCY (Hz) FREQUENCY (Hz) PIN TO PIN RESISTANCE (k Ω) AMS9 Divider Resistance Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

8 AMS9/AMS9 TYPICAL PERFORMANCE CHARACTERISTICS (Continued) SHUTDOWN TRESHOLD OLTAGE () Shutdown Treshold oltage.. REGULATOR OFF.. REGULATOR ON OUTPUT OLTAGE CHANGE () Line Regulation I L = µa T J = C I L = ma ~ T J = C I L = µa - - OLTAGE () OUTPUT CURRENT ( ma) AMS9 Maximum Rated Output Current T A = C T A = C PIN MOLDED DIP SOLDERED TO PC BOARD T JMAX = C OUT = T A = C OLTAGE () OUTPUT CURRENT ( ma) AMS9 Maximum Rated Output Current T A = C TO-9 PACKAGE."LEADS SOLDERED TO PC BOARD T JMAX = C T A = C OLTAGE () OUTPUT OLTAGE CHANGE (m) POWER DISSIPATION (W) Thermal Response - ~.W - TIME (µs) Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

9 AMS9/AMS9 APPLICATION HINTS External Capacitors A. µf or greater capacitor is required between output and ground for stability at output voltages of or more. At lower output voltages, more capacitance is required (.µ or more is recommended for and. versions). Without this capacitor the part will oscillate. Most types of tantalum or aluminum electrolytic works fine here; even film types work but are not recommended for reasons of cost. Many aluminum types have electrolytes that freeze at about - C, so solid tantalums are recommended for operation below - C. The important parameters of the capacitor are an ESR of about Ω or less and resonant frequency above khz parameters in the value of the capacitor. The value of this capacitor may be increased without limit. At lower values of output current, less output capacitance is required for stability. The capacitor can be reduced to. µf for currents below ma or. µf for currents below ma. Using the adjustable versions at voltages below runs the error amplifier at lower gains so that more output capacitance is needed. For the worst-case situation of a ma load at. output (Output shorted to Feedback) a.µf (or greater) capacitor should be used. Unlike many other regulators, the AMS9, will remain stable and in regulation with no load in addition to the internal voltage divider. This is especially important in CMOS RAM keep-alive applications. When setting the output voltage of the AMS9 version with external resistors, a minimum load of µa is recommended. A µf tantalum or aluminum electrolytic capacitor should be placed from the AMS9/AMS9 input to the ground if there is more than inches of wire between the input and the AC filter capacitor or if a battery is used as the input. Stray capacitance to the AMS9 Feedback terminal can cause instability. This may especially be a problem when using a higher value of external resistors to set the output voltage. Adding a pf capacitor between Output and Feedback and increasing the output capacitor to at least. µf will fix this problem. Error Detection Comparator Output The comparator produces a logic low output whenever the AMS9 output falls out of regulation by more than approximately %. This figure is the comparator s built-in offset of about m divided by the. reference voltage (Refer to the block diagram). This trip level remains % below normal regardless of the programmed output voltage of the 9. For example, the error flag trip level is typically. for a output or. for a output. The out of regulation condition may be due either to low input voltage, current limiting, or thermal limiting. Figure gives a timing diagram depicting the signal and the regulator output voltage as the AMS9 input is ramped up and down. For versions the signal becomes valid (low) at about. input. It goes high at about input (the input voltage at which out =. ). Since the AMS9 s dropout voltage is load dependent (see curve in typical performance characteristics), the input voltage trip point (about ) will vary with the load current. The output voltage trip point (approx..) does not vary with load. The error comparator has an open-collector output which requires an external pull-up resistor. This resistor may be returned to the output or some other supply voltage depending on system requirements. In determining a value for this resistor, note that the output is rated to sink µa, this sink current adds to battery drain in a low battery condition. Suggested values range from K to MΩ. The resistor is not required if this output is unused. Programming the Output oltage (AMS9) The AMS9 may be pin-strapped for the nominal fixed output voltage using its internal voltage divider by tying the output and sense pins together, and also tying the feedback and TAP pins together. Alternatively, it may be programmed for any output voltage between its. reference and its maximum rating. As seen in Figure, an external pair of resistors is required. The complete equation for the output voltage is: out = REF ( R / R ) I FB R where REF is the nominal. reference voltage and I FB is the feedback pin bias current, nominally - na. The minimum recommended load current of µa forces an upper limit of. MΩ on value of R, if the regulator must work with no load (a condition often found in CMOS in standby) I FB will produce a % typical error in OUT which may be eliminated at room temperature by trimming R. For better accuracy, choosing R = k reduces this error to.% while increasing the resistor program current by µa. Since the AMS9 typically draws µa at no load with Pin open-circuited, this is a small price to pay. Reducing Output Noise In reference applications it may be an advantageous to reduce the AC noise present at the output. One method is to reduce the regulator bandwidth by increasing the size of the output capacitor. This is the only way that noise can be reduced on the lead AMS9 but is relatively inefficient, as increasing the capacitor from µf to µf only decreases the noise from µ to µ rms for a khz bandwidth at output. Noise could also be reduced fourfold by a bypass capacitor across R, since it reduces the high frequency gain from to unity. Pick C BYPASS / πr Hz or about. µf. When doing this, the output capacitor must be increased to. µf to maintain stability. These changes reduce the output noise from µ to µ rms for a khz bandwidth at output. With the bypass capacitor added, noise no longer scales with output voltage so that improvements are more dramatic at higher output voltages. Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

10 AMS9/AMS9 APPLICATION HINTS (Continued) IN OUTPUT OLTAGE. k * OLTAGE. OUPUT **SHUTDOWN IN * OUT SD AMS9 FB. R OUT. *. µf.µf REF R FIGURE. Output Timing *When IN. the error flag pin becomes a high impedance, and the error flag voltage rises to its pull-up voltage. Using out as the pull-up voltage (see Figure ), rather than an external source, will keep the error flag voltage under. (typ.) in this condition. The user may wish to drive down the error flag voltage using equal value resistors ( kω suggested), to ensure a lowlevel logic signal during any fault condition, while still allowing a valid high logic level during normal operation. FIGURE. Adjustable Regulator *See Application Hints. out = REF ( R / R ) **Drive with TTL- high to shut down. Ground or leave if shutdown feature is not used. Note: Pins and are left open. TYPICAL APPLICATIONS ma Regulator with. Dropout Wide Input oltage Range Current Limiter UNREGULATED IN OUT Ω N () IN AMS9 TAP SENSE FB.µF kω LOAD ma TO ma OUTPUT OUPUT SHUTDOWN IN OUT AMS9 SD FB * OUT ΙΝ *Minimum Input-Output voltage ranges from m to m, depending on load current. Current limit is typically ma Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

11 AMS9/AMS9 TYPICAL APPLICATIONS (Continued) Low Drift Current Source olt Current Limiter = I L LOAD BUS IN IN OUT AMS9 -. * OUT SHUTDOWN AMS9 SD FB.µF OUT µf R % µf *Minimum Input-Output voltage ranges from m to m, depending on load current. Current limit is typically ma Regulator with. Sleep Function Open Circuit Detector for to ma Current Loop IN *SLEEP C - MOS GATE ma.kω *OUTPUT OUPUT SHUTDOWN kω IN SD AMS9 OUT FB pf kω N9 OUT kω %.µf kω N.µF IN OUT AMS9 FB N % kω MIN. OLTAGE Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

12 AMS9/AMS9 TYPICAL APPLICATIONS (Continued) Ampere Low Dropout Regulator Regulator with Early Warning and Auxiliary Output CURRENT LIMIT SECTION IN = OUT. IN D N9.MΩ kω. MJE9 A IN SENSE TAP OUT AMS9 # FB D µf MEMORY SUPPLY. NICAD IN AMS9 SD FB FLAG R %. TANT. µf.mω D kω D EARLY WARNING kω. OUT R Q IN TAP SENSE OUT FB AMS9 # SD kω MAIN OUTPUT µf RESET µp DD OUT =.(R/R) For OUT, use internal resistors. Wire pin to and pin to OUT Buss. Early warning flag on low input voltage Main output latches off at lower input voltages Battery backup on auxiliary output Operation: Reg.# s OUT is programmed one diode drop above. It s error flag becomes active when IN.. When IN drops below., the error flag of Reg.# becomes active and via Q latches the main output off. When IN again exceeds. Reg.# is back in regulation and the early warning signal rises, unlatching Reg.# via D. A Regulator with. Dropout Latch Off When Error Flag Occurs UNREGULATED IN µf kω.µf ΜΩ IN TAP SENSE AMS9 FB OUT.µF kω SUPERTEX PC µf I Q µa OUTPUT ± TO A kω IN OUT kω AMS9 SD FB RESET R R OUT µf Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

13 AMS9/AMS9 PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted. LEAD TO-9 PLASTIC PACKAGE (N).±. (.±.) DIA.±. (.±.).±. (.±.).9 (.) NOM.±. (.±.).±. (.±.). (.) MIN. (.) MAX UNCONTROLLED LEAD DIMENSIONS NOM NOM.±. (.±.).±. (.±.).±. (.±.) N (TO-9 ) AMS DRW# 9 LEAD SOIC PLASTIC PACKAGE (S).9-.9* (.-.).-. (.9-.9).-.** (.-.9).-.9 (.-.).-. (.-.).-. (.-.).-. (.-.) x - TYP.-.9 (.-.). (.) TYP.-. (.-.) S (SO- ) AMS DRW# 9 *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED." (.mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED." (.mm) PER SIDE Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

14 PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted (Continued). AMS9/AMS9 LEAD PLASTIC DIP PACKAGE (P).* (.) MAX.±.* (.±.).-. (.-.).±. (.±.).-. (.-.). (.) TYP. (.) MIN.±. (.±.). (.) MIN.±. (.±.). (.) MIN.9-. (.9-.).. -. (.. ) -. *DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTUSIONS. MOLD FLASH OR PROTUSIONS SHALL NOT EXCEED." (.mm) P (L PDIP ) AMS DRW# 9 Advanced Monolithic Systems, Inc. Phone (9) - Fax (9) -

AS ma Low Drop Out Voltage Regulator

AS ma Low Drop Out Voltage Regulator ma Low Drop Out oltage Regulator FEATURES Output Accuracy, 3.3,@ ma Output ery Low Quiescent Current Low Dropout oltage Extremely Tight Load And Line Regulation ery Low Temperature Coefficient Current