Si91842/4 New Product Vishay Siliconix 150-mA Low-Noise LDO Regulator With Error Flag and Discharge Option FEATURES D D D D D D D D D D D D D D D Si91842: Output—Auto-Discharge In Shutdown Mode D Si91844: Output—No-Discharge In Shutdown Mode D Fixed 1.2, 1.8, 2.0, 2.2, 2.5, 2.6, 2.7, 2.8, 2.85, 2.9, 3.0, 3.3, 3.5, 3.6, 5.0-V Output Voltage Options D SOT23-5 Package Ultra Low Dropout—130 mV at 150-mA Load Low Noise—75 mV(rms) (10-Hz to 100-kHz Bandwidth) Out-of-Regulation Error Flag (power good) Shutdown Control 110-mA Ground Current at 150-mA Load Fast Start-Up (50 mS) 1.5% Guaranteed Output Voltage Accuracy (1.2 V, 2%) 300-mA Peak Output Current Capability Uses Low ESR Ceramic Capacitors Fast Line and Load Transient Response (v 30 ms) 1-mA Maximum Shutdown Current Output Current Limit Reverse Battery Protection Built-in Short Circuit and Thermal Protection APPLICATIONS D Cellular Phones, Wireless Handsets D Noise-Sensitive Electronic Systems, Laptop and Palmtop Computers D PDAs D Pagers D Digital Cameras D MP3 Player D Wireless Modem DESCRIPTION pull-down circuit is built into the Si91842/4 to clamp the output voltage when it rises beyond normal regulation. The Si91842 automatically discharges the output voltage by connecting the output to ground through a 100-W n-channel MOSFET when the device is put in shutdown mode. The Si91842/4 is a 150-mA CMOS LDO (low dropout) voltage regulator. It is the perfect choice for low voltage, low power applications. An ultra low ground current and ultra fast turn-on make this part attractive for battery operated power systems. The Si91842/4 also offers ultra low dropout voltage to prolong battery life in portable electronics. Systems requiring a quiet voltage source will benefit from the Si91842/4’s low output noise. The Si91842/4 is designed to maintain regulation while delivering 300-mA peak current, making it ideal for systems that have a high surge current upon turn-on. The Si91842/4 features reverse battery protection to limit reverse current flow to approximately 1-mA in the event reversed battery is applied at the input, thus preventing damage to the IC. For better transient response and regulation, an active TYPICAL APPLICATION CIRCUIT Si91842/4 VIN 1 VIN VOUT 5 VOUT 1 mF SD 1 mF 2 GND 3 SD 5 ERROR 4 51 kW ERROR SOT-23, 5-Lead Document Number: 71732 S-20478—Rev. C, 01-Apr-02 www.vishay.com 1 Si91842/4 New Product Vishay Siliconix ABSOLUTE MAXIMUM RATINGS Package Thermal Resistance, (qJA)a . . . . . . . . . . . . . . . . . . . . . . . . . 180_C/W Absolute Maximum Ratings Input Voltage, VIN to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –6.0 to 6.5 V Maximum Junction Temperature, TJ(max) . . . . . . . . . . . . . . . . . . . . . . . 150_C VERROR, VSD (See Detailed Description) . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to VIN Storage Temperature, TSTG . . . . . . . . . . . . . . . . . . . . . . . . . . –65_C to 150_C Output Current, IOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Short Circuit Protected Notes a. Device mounted with all leads soldered or welded to PC board. b. Derate 5.5 mW/_C above TA = 70_C Output Voltage, VOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to VIN + 0.3 V Package Power Dissipation, (Pd)b . . . . . . . . . . . . . . . . . . . . . . . . . . . 440 mW Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and 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 affect device reliability. RECOMMENDED OPERATING RANGE Input Voltage, VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 V to 6 V Input Voltage, VSD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 V to VIN Operating Ambient Temperature, TA . . . . . . . . . . . . . . . . . . . . –40_C to 85_C CIN = COUT = 1 mF (ceramic) Maximum ESR of COUT: 0.4 W SPECIFICATIONS Limits Test Conditions Unless Specified Parameter Symbol Input Voltage Range TA = 25_C, _ VIN = VOUT(nom) + 1 V, IOUT = 1 mA, CIN = 1 mF, COUT = 1.0 mF, VSD = 1.5 V VIN VOUT w 1.8 V Line Regulation (3.0 V < VOUT v3.6 V) DVIN VIN – VOUT 1 1.5 2.5 2.0 Full –3.0 1 3.0 Full –0.06 0.18 Full 0 0.3 From VIN = 5.5 V to 6 V Full 0 0.4 IOUT = 1 mA Room 1 Room 45 Full 50 90 Room 130 180 IOUT = 150 mA IOUT = 150 mA Full Full IOUT = 0 mA IGND Full Output Noise Voltage www.vishay.com 2 Full Full Full eN VOUT = 2.6 V, BW = 10 Hz to 100 kHz, 0 mA t IOUT t 150 mA Room 170 m mA 200 120 Full VOUT w 0.95 x VOUT(nom). tPW = 2 ms 200 230 110 Full IO(peak) 150 180 110 Room IOUT = 150 mA 250 300 100 Room IOUT = 0 mA mV 100 120 190 Room IOUT = 150 mA %/V 80 220 65 Room Peak Output current % From VIN = VOUT(nom) + 1 V to VOUT(nom) + 2 V Room Ground Pin Currente, g (VOUT(nom) u 3 V) V 2 –1.5 1 IOUT = 50 mA Ground Pin Currente, g (VOUT(nom) v 3 V) 6 Full Room Room Dropout Voltaged, g (VOUT(nom) t 2.6 V, VIN w 2 V) Unit 1 IOUT = 50 mA Dropout Voltaged, g (VOUT(nom) w 2.6 V) Maxb –2.0 VOUT(nom) Line Regulation (5-V Version) Typc –2.5 Line Regulation (VOUT v 3 V) 100 Minb Full VOUT = 1.2 V DVOUT Tempa Room 1 mA v IOUT v 150 mA Output Voltage Accuracy –40 to 85_C 200 230 300 mA 75 mV(rms) Document Number: 71732 S-20478—Rev. C, 01-Apr-02 Si91842/4 New Product Vishay Siliconix SPECIFICATIONS Limits Test Conditions Unless Specified Parameter Ripple Rejection TA = 25_C, VIN = VOUT(nom) + 1 V, IOUT = 1 mA, CIN = 1 mF, COUT = 1.0 mF, VSD = 1.5 V Symbol DVOUT/DVIN IOUT = 150 mA –40 to 85_C Tempa Minb Typc f = 1 kHz Room 60 f = 10 kHz Room 40 f = 100 kHz Room 30 Dynamic Line Regulation DVO(line) VIN : VOUT(nom) + 1 V to VOUT(nom) + 2 V tr/tf = 2 ms, IOUT = 150 mA Room 20 Dynamic Load Regulation DVO(load) IOUT : 1 mA to 150 mA, tr/tf = 2 ms Room 25 Maxb Unit dB mV Thermal Shutdown Junction Temperature TJ(S/D) Room 150 Thermal Hysteresis THYST Room 20 _C C Reverse current IR VIN = –6.0 V Room 1 mA Short Circuit Current ISC VOUT = 0 V Room 700 mA Shutdown Shutdown Supply Current SD Pin Input Voltage ICC(off) VSD VSD = 0 V Room High = Regulator ON (Rising) Full Low = Regulator OFF (Falling) Full 0.1 1.5 1 VIN 0.4 mA V Auto Discharge Resistance R_DIS Si91842 Only Room 100 W SD Pin Input Currentf IIN(SD) VSD = 1.5 V, VIN = 6 V Room 0.7 mA Full 150 mV tON VSD (See Figure 1), ILOAD = 100 mA Room 50 mS ERROR High Leakage IOFF ERROR v VIN. VOUT in Regulation Full 1 mA ERROR Low Voltage VOL ISINK = 0.5 mA Full 0.4 V Full VERROR VOUT Below VOUT(nom)g, VIN w 2 V VOUT Falling, IOUT = 1 mA, VOUT(nom) w 2 V VOUT(nom)g t 2 V, VIN u 2 V Full –4 Room 1.5 SD Hysteresis VOUT Turn-On Time VHYST(SD) ERROR Output ERROR Voltage Threshold ERROR Voltage Threshold Hysteresis VHYST(ERROR) –2 –4 –6 % Notes a. Room = 25_C, Full = –40 to 85_C. b. The algebraic convention whereby the most negative value is a minimum and the most positive a maximum. c. Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing. d. Dropout voltage is defined as the input to output differential voltage at which the output voltage drops 2% below the output voltage measured with a 1-V differential, provided that VIN does not not drop below 2.0 V. e. Ground current is specified for normal operation as well as “drop-out” operation. f. The device’s shutdown pin includes a typical 2-MW internal pull-down resistor connected to ground. g. VOUT(nom) is VOUT when measured with a 1-V differential to VIN. TIMING WAVEFORMS VIN VSD 0V tr v 1 mS tON VNOM 0.95 VNOM VOUT FIGURE 1. Timing Diagram for Power-Up Document Number: 71732 S-20478—Rev. C, 01-Apr-02 www.vishay.com 3 Si91842/4 New Product Vishay Siliconix PIN CONFIGURATION SOT-23, 5-Lead VIN 1 GND 2 SD 3 5 VOUT 4 ERROR PIN DESCRIPTION Pin Number Name 1 VIN 2 GND Function Input supply pin. Bypass this pin with a 1-mF ceramic or tantalum capacitor to ground Ground pin. For better thermal capability, directly connected to large ground plane 3 SD 4 ERROR By applying less than 0.4 V to this pin, the device will be turned off. Connect this pin to VIN if unused 5 VOUT The open drain output is an error flag output which goes low when VOUT drops 4% below its nominal voltage. Output voltage. Connect COUT between this pin and ground. ORDERING INFORMATION Si91842 Part Number Marking Voltage Si91842DT-12-T1b J8LLL Si91842DT-18-T1 C8LLL Si91842DT-20-T1 Si91844 Temp. Range Part Number Marking Voltage 1.2 Si91844DT-18-T1 F6LLL 1.8 1.8 Si91844DT-20-T1 F7LLL 2.0 C9LLL 2.0 Si91844DT-22-T1 F8LLL 2.2 Si91842DT-22-T1 C0LLL 2.2 Si91844DT-25-T1 F9LLL 2.5 Si91842DT-25-T1 D1LLL 2.5 Si91844DT-26-T1 F0LLL 2.6 Si91842DT-26-T1 D2LLL 2.6 Si91844DT-27-T1 G1LLL 2.7 Si91842DT-27-T1 D3LLL 2.7 Si91844DT-28-T1 G2LLL 2.8 Si91842DT-28-T1 D4LLL 2.8 Si91844DT-285-T1 G3LLL 2.85 Si91842DT-285-T1 D5LLL 2.85 Si91844DT-29-T1 G4LLL 2.9 Si91842DT-29-T1 D6LLL 2.9 Si91844DT-30-T1 G5LLL 3.0 Si91842DT-30-T1 D7LLL 3.0 Si91844DT-33-T1 G6LLL 3.3 Si91842DT-33-T1 D8LLL 3.3 Si91844DT-35-T1 G7LLL 3.5 Si91842DT-35-T1 D9LLL 3.5 Si91844DT-36-T1 G8LLL 3.6 Si91842DT-36-T1 D0LLL 3.6 Si91844DT-50-T1 G9LLL 5.0 Si91842DT-50-T1 E1LLL 5.0 –40 to 85_C Pkg. SOT23-5 Temp. Range Pkg. –40 to 85_C _ SOT23-5 Notes: a. LLL = Lot Code b. Advanced Information, available March 2002. www.vishay.com 4 Document Number: 71732 S-20478—Rev. C, 01-Apr-02 Si91842/4 New Product Vishay Siliconix TYPICAL CHARACTERISTICS (INTERNALLY REGULATED, 25_C UNLESS NOTED) Normalized Output Voltage vs. Load Current Normalized VOUT vs. Temperature 0.30 0.4 VIN = VOUT(nom) + 1 V VIN = VOUT(nom) + 1 V 0.15 0.2 0.00 –0.0 V OUT (%) Output Voltage (%) IOUT = 0 mA –0.15 –0.30 IOUT = 75 mA –0.2 –0.45 –0.6 –0.60 –0.8 –0.75 0 25 50 75 100 125 IOUT = 150 mA –0.4 –1.0 –40 150 –15 Load Current (mA) 10 35 60 85 Ambient Temperature (_C) GND Current vs. Load Current No Load GND Pin Current vs. Input Voltage 300 150 VOUT = 3.0 V VIN = 4.0 V 85_C 250 125 200 I GND ( mA) I GND ( mA) 25_C 100 –40_C 150 85_C 25_C 100 –40_C 75 50 50 0 0 25 50 75 100 125 150 2 3 Load Current (mA) 4 5 6 7 Input Voltage (V) Power Supply Rejection Output Short Circuit Current vs. Temperature 750 0 VOUT = 2.6 V CIN = 1 mF COUT = 1 mF ILOAD = 150 mA VOUT = 3.0 V –20 725 I SC (mA) Gain (dB) 700 –40 675 650 –60 625 –80 10 100 1000 10000 Frequency (Hz) Document Number: 71732 S-20478—Rev. C, 01-Apr-02 100000 1000000 600 –40 –15 10 35 60 85 AmbientTemperature (_C) www.vishay.com 5 Si91842/4 New Product Vishay Siliconix TYPICAL CHARACTERISTICS (INTERNALLY REGULATED, 25_C UNLESS NOTED) Dropout Voltage vs. Load Current VIN – VOUT Transfer Characteristic 3.0 350 VOUT = 3.0 V VOUT = 3.0 V 300 2.5 2.0 V OUT (V) V DROP (mV) 250 200 150 1.5 1.0 100 0.5 50 0 0.0 0 60 120 180 240 0 300 1 2 3 ILOAD (mA) 4 5 6 VIN (V) Dropout Voltage vs. Temperature Dropout Voltage vs. VOUT 350 400 VOUT = 3.0 V 350 300 IOUT = 300 mA Dropout Voltage (mV) V DROP (mV) 200 IOUT = 150 mA 150 100 6 200 150 IOUT = 150 mA IOUT = 75 mA 50 IOUT = 10 mA IOUT = 0 mA –25 0 25 50 75 100 Junction Temperature (_C) www.vishay.com 250 100 IOUT = 75 mA 50 0 –50 IOUT = 300 mA 300 250 125 150 0 1.0 IOUT = 10 mA 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 VOUT Document Number: 71732 S-20478—Rev. C, 01-Apr-02 Si91842/4 New Product Vishay Siliconix TYPICAL WAVEFORMS Load Transient Response-1 Load Transient Response-2 VOUT 10 mV/div VOUT 10 mV/div ILOAD 100 mA/div ILOAD 100 mA/div 20 ms/div 20 ms/div VOUT = 3.0 V COUT = 1 mF ILOAD = 1 to 150 mA trise = 2 msec VOUT = 3.0 V COUT = 1 mF ILOAD = 150 to 1 mA tfall = 2 msec LineTransient Response-1 LineTransient Respons-2 VOUT 10 mV/div VOUT 10 mV/div VIN 2 V/div VIN 2 V/div 20 ms/div 20 ms/div VINSTEP = 4 to 5 V VOUT = 3 V COUT = 1 mF CIN = 1 mF ILOAD = 150 mA trise = 5 msec Document Number: 71732 S-20478—Rev. C, 01-Apr-02 VINSTEP = 5 to 4 V VOUT = 3 V COUT = 1 mF CIN = 1 mF ILOAD = 150 mA tfall = 5 msec www.vishay.com 7 Si91842/4 Vishay Siliconix New Product TYPICAL WAVEFORMS Output Noise Noise Spectrum Output Spectral Noise Density 10 VOUT 200 mV/div mVń ǸHz 0.01 4 ms/div 10 Hz VIN = 4 V VOUT = 3 V IOUT = 150 mA BW = 10 Hz to 100 kHz www.vishay.com 8 1 MHz VIN = 4 V VOUT = 3 V ILOAD = 150 mA Document Number: 71732 S-20478—Rev. C, 01-Apr-02 Si91842/4 New Product Vishay Siliconix BLOCK DIAGRAM Si91842/4 VIN Reverse Polarity Protection Reference – + VOUT Thermal Sensor Si91842 Only Current Limit ERROR SD Shutdown Control GND DETAILED DESCRIPTION The Si91842/4 is a low-noise, low drop-out and low quiescent current linear voltage regulator, packaged in a small footprint SOT23-5 package. The Si91842/4 can supply loads up to 300 mA. As shown in the block diagram, the circuit consists of a bandgap reference, error amplifier, p-channel pass transistor and feedback resistor string. Additional blocks, not shown in the block diagram, include a precise current limiter, reverse battery and current protection, and thermal sensor. protection is desired. Hardwiring the SD pin directly to the VIN pin is allowed when reverse battery protection is not desired. ERROR ERROR is an open drain output that goes low when VOUT is less than 4% of its normal value. To obtain a logic level output, connect a pull-up resister from ERROR to VOUT or any other voltage equal to or less than VIN. ERROR pin is high impedance (off) when SD pin is low. Thermal Overload Protection The thermal overload protection limits the total power dissipation and protects the device from being damaged. When the junction temperature exceeds 150_, the device turns the p-channel pass transistor off. Reverse Battery Protection The Si91842/4 has a battery reverse protection circuitry that disconnects the internal circuitry when VIN drops below the GND voltage. There is no current drawn in such an event. When the SD pin is hardwired to VIN, the user must connect the SD pin to VIN via a 100-kW resistor if reverse battery Document Number: 71732 S-20478—Rev. C, 01-Apr-02 Auto-Discharge/No-Discharge VOUT has an internal 100-W (typ.) discharge path to ground when SD pin is low for the Si91842. the Si91844 does not have a discharge path when the SD pin is low. Stability The circuit is stable with only a small output capacitor equal to 6 nF/mA (= 1 mF @ 150 mA). Since the bandwidth of the error amplifier is around 1–3 MHz and the dominant pole is at the output node, the capacitor should be capacitive in this range, i.e., for 150-mA load current, an ESR <0.4 W is necessary. Parasitic inductance of about 10 nH can be tolerated. www.vishay.com 9