RT9167/A. Low-Noise, Fixed Output Voltage, 200mA/500mA LDO Regulator. General Description. Features. Applications. Pin Configurations

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1 Low-Noise, Fixed Output Voltage, 2mA/5mA LDO Regulator General Description he is a 2mA/5mA low dropout and low noise micropower regulator suitable for portable applications. he output voltages range from 1.5V to 5.V in 1mV increments and 2% accuracy. he is designed for use with very low ESR capacitors. he output remains stable even with 1µF ceramic output capacitor. he uses and internal PMOS as the pass device, which does not cause extra GND current in heavy load and dropout conditions. he shutdown mode of nearly zero operation current makes the IC suitable for battery-power devices. Other features include a reference bypass pin to improve low noise performance, current limiting, and over temperature protection. Ordering Information - Package type B : SO-25 ype I BR : SO-25 ype II S : SOP-8 Operating temperature range C: Commercial standard Output voltage 15 : 1.5V 16 : 1.6V : : 49 : 4.9V 5 : 5.V 5mA Output current 2mA Output current Features Stable with Low-ESR Output Capacitor Low Dropout Voltage (22mV and 2mA) Low Operation Current - 8µA ypical Shutdown Function Low Noise Output Low emperature Coefficient Current and hermal Limiting Custom Voltage Available SO-25 and SOP-8 Packages Applications Cellular elephones Laptop, Notebook, and Palmtop Computers Battery-powered Equipment Hand-held Equipment Pin Configurations Part Number - CB (Plastic SO-25) - CBR (Plastic SO-25) - CS (Plastic SOP-8) Pin Configurations OP VIEW SHDN IN OU BP OP VIEW 1. IN 2. GND 3. SHDN 4. BP 5. OU OP VIEW 1. OU 2. GND 3. IN 4. SHDN 5. BP 8 GND 7 GND 6 GND 5 GND DS9167/A-1 July

2 DS9167/A-1 July 21 2 Marking Information Part Number Marking R CB E R CB E1 R CB E2 R CB E3 R CB E4 R9167-2CB E5 R CB E6 R CB E7 R CB E8 R CB E9 R CB EA R CB EB R CB EC R CB ED R CB EE R9167-3CB EF R CB EG R CB EH R CB EJ R CB EK R CB EL R CB EM R CB EN R CB EP R CB EQ R9167-4CB ER R CB ES R CB E R CB EU R CB EV R CB EW R CB EX R CB EY R CB EZ R CB AR Part Number Marking R9167-5CB AS R9167A-15CB J R9167A-16CB J1 R9167A-17CB J2 R9167A-18CB J3 R9167A-19CB J4 R9167A-2CB J5 R9167A-21CB J6 R9167A-22CB J7 R9167A-23CB J8 R9167A-24CB J9 R9167A-25CB JA R9167A-26CB JB R9167A-27CB JC R9167A-28CB JF R9167A-29CB JE R9167A-3CB JD R9167A-31CB JG R9167A-32CB JH R9167A-33CB JJ R9167A-34CB JK R9167A-35CB JL R9167A-36CB JM R9167A-37CB JN R9167A-38CB JP R9167A-39CB JQ R9167A-4CB JR R9167A-41CB JS R9167A-42CB J R9167A-43CB JU R9167A-44CB JV R9167A-45CB JW R9167A-46CB JX R9167A-47CB JY R9167A-48CB JZ

3 DS9167/A-1 July Part Number Marking R9167A-49CB CA R9167A-5CB CB R CBR I R CBR I1 R CBR I2 R CBR I3 R CBR I4 R9167-2CBR I5 R CBR I6 R CBR I7 R CBR I8 R CBR I9 R CBR IA R CBR IB R CBR IC R CBR ID R CBR IE R9167-3CBR IF R CBR IG R CBR IH R CBR IJ R CBR IK R CBR IL R CBR IM R CBR IN R CBR IP R CBR IQ R9167-4CBR IR R CBR IS R CBR I R CBR IU R CBR IV R CBR IW R CBR IX R CBR IY R CBR IZ R CBR CY Part Number Marking R9167-5CBR CZ R9167A-15CBR K R9167A-16CBR K1 R9167A-17CBR K2 R9167A-18CBR K3 R9167A-19CBR K4 R9167A-2CBR K5 R9167A-21CBR K6 R9167A-22CBR K7 R9167A-23CBR K8 R9167A-24CBR K9 R9167A-25CBR KA R9167A-26CBR KB R9167A-27CBR KC R9167A-28CBR KD R9167A-29CBR KE R9167A-3CBR KF R9167A-31CBR KG R9167A-32CBR KH R9167A-33CBR KJ R9167A-34CBR KK R9167A-35CBR KL R9167A-36CBR KM R9167A-37CBR KN R9167A-38CBR KP R9167A-39CBR KQ R9167A-4CBR KR R9167A-41CBR KS R9167A-42CBR K R9167A-43CBR KU R9167A-44CBR KV R9167A-45CBR KW R9167A-46CBR KX R9167A-47CBR KY R9167A-48CBR KZ R9167A-49CBR CC R9167A-5CBR CD

4 Pin Description Pin Name Pin Function IN Input GND Ground SHDN Active Low Shutdown Input BP Reference Noise Bypass OU Output Function Block Diagram SHDN Shutdown and Logic Control IN BP VREF + _ Error Amp MOS Driver Current-Limit and hermal Protection OU GND ypical Application Circuit V IN ON OFF C IN 1µF R9167 IN OU V OU GND SHDN BP C OU 1µF C BP 1nF DS9167/A-1 July 21 4

5 Absolute Maximum Ratings Input Voltage Power Dissipation, P A = 25 C SO-25.25W SOP-8.625W Operating Junction emperature Range 4 C to 125 C Storage emperature Range 65 C to 15 C Package hermal Resistance SO-25, θ JA SOP-8, θ JA 8V 25 C/W 16 C/W Lead emperature (Soldering, 5 sec.) 26 C Electrical Characteristics (V IN = 5.V, C IN = 1µF, C OU = 1µF, A = 25 C, unless otherwise specified) Parameter Symbol est Conditions Min yp Max Units Input Voltage Range V IN I L = 5mA Output Voltage Accuracy V OU I L = 1mA % Maximum Output R Current R9167A I MAX Current Limit GND Pin Current Dropout Voltage (Note) (V OU (Nominal) 3.V Version) R R9167A I LIMI R LOAD = 1Ω No Load R9167 I G I OU = 2mA R9167A I OU = 5mA I OU = 1mA I OU = 5mA V DROP I OU = 2mA R9167A I OU = 5mA Line Regulation V LINE V IN = (V OU +.15) to 7V, I OU = 1mA %/V Load Regulation R9167 I OU = ma to 2mA V LOAD R9167A IOU = ma to 5mA SHDN Input High hreshold V IH V IN = 3V to 5.5V V SHDN Input Low hreshold V IL V IN = 3V to 5.5V V SHDN Bias Current I SD na Shutdown Supply Current I GSD V OU = V µa hermal Shutdown emperature SD C V ma ma µa mv %/ma Output Noise e NO C BP = 1nF, C OU = 1µF nv Hz Ripple Rejection PSRR F = 1Hz, C BP = 1nF, C OU = 1µF db Notes: Dropout voltage definition: V IN - V OU when V OU is 5 mv below the value of V OU at V IN = V OU +.5V DS9167/A-1 July

6 ypical Operating Charateristics 3.33 Output Voltage vs. emp. 12 GND Current vs. emp Output Voltage (V) V OU = 3.3V emperature ( C) GND Current ( µ A) V OU = 3.3V emperature ( C) 3 Dropout Voltage vs. Output Current 48 Current Limit vs. emp. Dropout Voltage (mv) (V) C 25 C -4 C V OU = 3.3V Output Current (ma) Current Limit (ma) R9167 V OU = 3.3V emperature ( C ) 9 Current Limit vs. emp. 7 PSRR 8 6 Current Limit (ma) R9167A V OU = 3.3V emperature ( C) PSRR (db) I LOAD = 1mA, C OU = 4.7µF V OU = 3.3V, C BP = 1nF K 1 1 1K 1K 1 1 1M Frequency (KHz) DS9167/A-1 July 21 6

7 Output Voltage Deviation (mv) > Load ransient Response C OU = 1µF C IN = 1µF C BP = 1nF V OU = 3.V V IN = 4V Output Voltage Deviation (mv) > Load ransient Response C OU = 4.7µF C IN = 1µF C BP = 1nF V OU = 3.V V IN = 4V Load Current (ma) > ime (5µS/Div) Load Current (ma) > ime (5µS/Div) Input Voltage (V) Output Voltage (mv) > Line ransient Response C OU = 1µF V OU = 3.V Loading = 1mA ime (1mS/Div) C BP = 1nF Input Voltage (V) Output Voltage (mv) > Line ransient Response C OU = 1µF V OU = 3.V Loading = 5mA ime (1mS/Div) C BP = 1nF Input Voltage (V) Output Voltage (mv) > Line ransient Response C OU = 4.7µF V OU = 3.V Loading = 1mA ime (5µS/Div) C BP = 1nF Input Voltage (V) Output Voltage (mv) > Line ransient Response C OU = 4.7µF V OU = 3.V Loading = 5mA ime (5µS/Div) C BP = 1nF DS9167/A-1 July

8 Applications Guides Capacitor Selection and Regulator Stability Like any low-dropout regulator, the external capacitors used with the must be carefully selected for regulator stability and performance. Using a capacitor whose value is > 1µF on the input and the amount of capacitance can be increased without limit. he input capacitor must be located a distance of not more than.5" from the input pin of the IC and returned to a clean analog ground. Any good quality ceramic or tantalum can be used for this capacitor. he capacitor with larger value and lower ESR (equivalent series resistance) provides better PSRR and line-transient response. he output capacitor must meet both requirements for minimum amount of capacitance and ESR in all LDOs application. he is designed specifically to work with low ESR ceramic output capacitor in spacesaving and performance consideration. Using a ceramic capacitor whose value is at least 1uF with ESR is > 5mΩ on the output ensures stability. he still works well with output capacitor of other types due to the wide stable ESR range. Fig.1 shows the curves of allowable ESR range as a function of load current for various output voltages and capacitor values. Output capacitor of larger capacitance can reduce noise and improve load-transient response, stability, and PSRR. he output capacitor should be located not more than.5" from the V OU pin of the and returned to a clean analog ground. COU ESR (mω) (Ω) Ω Region of Stable C OU ESR vs. Load Current 1 C OU = 4.7µF Fig. 1 C OU = 1µF Load Current (ma) Note that some ceramic dielectrics exhibit large capacitance and ESR variation with temperature. It may be necessary to use 2.2µF or more to ensure stability at temperatures below -1 C in this case. Also, tantalum capacitors, 2.2µF or more may be needed to maintain capacitance and ESR in the stable region for strict application environment. antalum capacitors maybe suffer failure due to surge current when it is connected to a low-impedance source of power (like a battery or very large capacitor). If a tantalum capacitor is used at the input, it must be guaranteed to have a surge current rating sufficient for the application by the manufacture. Use a 1nF bypass capacitor at BP for low output voltage noise. he capacitor, in conjunction with an internal 2KΩ resistor, which connects bypass pin and the band-gap reference, creates an 8Hz lowpass filter for noise reduction. Increasing the capacitance will slightly decrease the output noise, but increase the start-up time. he capacitor connected to the bypass pin for noise reduction must have very low leakage. his capacitor leakage current causes the output voltage to decline by a proportional amount to the current due to the voltage drop on the internal 2KΩ resistor. Fig. 2 shows the power on response. DS9167/A-1 July 21 8

9 Voltage (.5V / DIV) C BP = 1nF C BP = 1nF V OU = 3.V ime (ms) Fig. 2 Internal P-Channel Pass ransistor he features a typical 1.1Ω P-channel MOSFE pass transistor. It provides several advantages over similar designs using PNP pass transistors, including longer battery life. he P-channel MOSFE requires no base drive, which reduces quiescent current considerably. PNP-based regulators waste considerable current in dropout when the pass transistor saturates. hey also use high base-drive currents under large loads. he does not suffer from these problems and consume only 8µA of quiescent current whether in dropout, light-load, or heavy-load applications. Input-Output (Dropout) Voltage Load-ransient Considerations he load-transient response graphs (see ypical Operating Characteristics) show two components of the output response: a DC shift from the output impedance due to the load current change, and the transient response. he DC shift is quite small due to the excellent load regulation of the IC. ypical output voltage transient spike for a step change in the load current from ma to 5mA is tens mv, depending on the ESR of the output capacitor. Increasing the output capacitor s value and decreasing the ESR attenuates the overshoot. Shutdown Input Operation he is shutdown by pulling the SHDN input low, and turned on by driving the input high. If this feature is not to be used, the SHDN input should be tied to VIN to keep the regulator on at all times (the SHDN input must not be left floating). o ensure proper operation, the signal source used to drive the SHDN input must be able to swing above and below the specified turn-on/turn-off voltage thresholds which guarantee an ON or OFF state (see Electrical Characteristics). he ON/OFF signal may come from either CMOS output, or an open-collector output with pull-up resistor to the input voltage or another logic supply. he high-level voltage may exceed the input voltage, but must remain within the absolute maximum ratings for the SHDN pin. A regulator s minimum input-output voltage differential (or dropout voltage) determines the lowest usable supply voltage. In battery-powered systems, this will determine the useful end-of-life battery voltage. Because the uses a P- channel MOSFE pass transistor, the dropout voltage is a function of drain-to-source on-resistance [R DS(ON) ] multiplied by the load current. Reverse Current Path he power transistor used in the has an inherent diode connected between the regulator input and output (see Fig.3). If the output is forced above the input by more than a diode-drop, this diode will become forward biased and current will flow from the V OU terminal to V IN. his diode will also be turned on by abruptly stepping the input voltage to a value below the output voltage. o prevent regulator mis-operation, a Schottky diode should be used in any applications where input/output voltage conditions can cause the internal diode to be turned on (see Fig.4). As shown, the Schottky diode is connected in parallel with the internal parasitic diode and prevents it from being turned on by limiting the voltage drop across it to about.3v. < 1 ma to prevent damage to the part. DS9167/A-1 July

10 V IN V IN Fig. 3 Fig. 4 V OU V OU Current Limit and hermal Protection he R9167 includes a current limit which monitors and controls the pass transistor s gate voltage limiting the output current to 3mA yp. (7mA yp. for R9167A). hermal-overload protection limits total power dissipation in the. When the junction temperature exceeds J = +155 C, the thermal sensor signals the shutdown logic turning off the pass transistor and allowing the IC to cool. he thermal sensor will turn the pass transistor on again after the IC s junction temperature cools by 1 C, resulting in a pulsed output during continuous thermal-overload conditions. hermal-overloaded protection is designed to protect the in the event of fault conditions. Do not exceed the absolute maximum junctiontemperature rating of J = +15 C for continuous operation. he output can be shorted to ground for an indefinite amount of time without damaging the part by cooperation of current limit and thermal protection. Operating Region and Power Dissipation he maximum power dissipation of depends on the thermal resistance of the case and circuit board, the temperature difference between the die junction and ambient air, and the rate of airflow. he power dissipation across the device is P = I OU (V IN - V OU ). he maximum power dissipation is: PMAX = ( J - A ) /θ JA where J - A is the temperature difference between the die junction and the surrounding environment, θ JA is the thermal resistance from the junction to the surrounding environment. he GND pin of the performs the dual function of providing an electrical connection to ground and channeling heat away. Connect the GND pin to ground using a large pad or ground plane. DS9167/A-1 July 21 1

11 Package Information D C B b A H e A1 L Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A A B b C D e H L SO- 25 Surface Mount Package DS9167/A-1 July

12 A H M J B F C D I Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A B C D F H I J M Lead SOP Plastic Package DS9167/A-1 July 21 12

13 DS9167/A-1 July

14 RICHEK ECHNOLOGY CORP. Headquarter 6F, No. 35, Hsintai Road, Chupei City Hsinchu, aiwan, R.O.C. el: (8863)55147 Fax: (8863) RICHEK ECHNOLOGY CORP. aipei Office (Marketing) 8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City aipei County, aiwan, R.O.C. el: (8862) Fax: (8862) DS9167/A-1 July 21 14