TK111xxM VOLTAGE REGULATOR WITH ON/OFF SWITCH FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ APPLICATIONS High Voltage Precision at ± 2.0% or ± 60 mV Active High On/Off Control Very Low Dropout Voltage (85 mV at 30 mA) Very Low Noise Miniature Package (SOT-23L-6) Internal Thermal Shutdown Short Circuit Protection Excellent Ripple Rejection (70 dB @ 1 kHz) Reverse Bias Protection ■ ■ ■ ■ ■ ■ ■ ■ Battery Powered Systems Cellular Telephones Pagers Personal Communications Equipment Portable Instrumentation Portable Consumer Equipment Radio Control Systems Toys DESCRIPTION The TK111xxM is a low dropout linear regulator with a builtin electronic switch. The internal switch can be controlled by TTL or CMOS logic levels. The device is in the “on” state when the control pin is pulled to a logic high level. An external capacitor can be connected to the noise bypass pin to lower the output noise level to 30 µVrms. TK111xxM An internal PNP pass transistor is used to achieve a low dropout voltage of 85 mV (typ.) at 30 mA load current. The TK111xxM has a very low quiescent current of 140 µA (typ.) at no load . The standby current is 100 nA maximum. The internal thermal shutdown circuitry limits the junction temperature to below 150 °C. The load current is internally monitored and the device will shut down in the presence of a short circuit or overcurrent condition at the output. CONTROL 20 P GND NOISE BYPASS VIN GND VOUT The TK111xxM is available in a miniature SOT-23L-6 surface mount package. ORDERING INFORMATION TK111 M L Tape/Reel Code Temp Code Product Code Voltage Code VOLTAGE CODE 20 = 2.0 V 21 = 2.1 V 22 = 2.2 V 23 = 2.3 V 24 = 2.4 V 25 = 2.5 V 27 = 2.7 V 28 = 2.8 V 29 = 2.9 V 30 = 3.0 V 31 = 3.1 V 32 = 3.2 V 33 = 3.3 V 34 = 3.4 V 35 = 3.5 V 36 = 3.6 V 37 = 3.7 V 38 = 3.8 V 39 = 3.9 V 40 = 4.0 V 41 = 4.1 V 42 = 4.2 V 43 = 4.3 V 44 = 4.4 V 45 = 4.5 V 46 = 4.6 V 47 = 4.7 V 48 = 4.8 V 49 = 4.9 V 50 = 5.0 V BLOCK DIAGRAM PACKAGE CODE M: SOT-23L-6 NOTE 1: 2.0 V to 2.3 V available in C temperature code (-30 to +80 °C) only. March 1999 TOKO, Inc. TAPE/REEL CODE L: Tape Left VIN VOUT THERMAL PROTECTION CONTROL TEMP. CODE: C: -30 to +80 °C I: -40 to +85 °C BANDGAP REFERENCE GND NOISE BYPASS Page 1 TK111xxM ABSOLUTE MAXIMUM RATINGS TK111xxMCL (VOUT ≥ 2.0 V) Supply Voltage ......................................................... 16 V Noise Bypass Terminal Voltage ................................. 5 V Power Dissipation (Note 1) ................................ 600 mW Reverse Bias ............................................................ 10 V Storage Temperature Range ................... -55 to +150 °C Operating Temperature Range ...................-30 to +80 °C Operating Voltage Range ............................... 1.8 to 12 V Junction Temperature ........................................... 150 °C Lead Soldering Temperature (10 s) ...................... 235 °C TK111xxMCL ELECTRICAL CHARACTERISTICS Test conditions: VIN = VOUT(TYP) + 1 V, TA = 25 °C, unless otherwise specified. SYMBOL PARAMETER TEST CONDITIONS IQ Quiescent Current IOUT = 0 mA, Excluding ICONT ISTBY Standby Current VIN = 6 V, Output OFF VOUT Output Voltage IOUT = 10 mA, VIN = VOUT(TYP) + 1 V Line Reg Line Regulation VIN = VOUT(TYP) + 1 V to VOUT(TYP) + 6 V, (Note 2) Load Reg Load Regulation MIN TYP MAX UNITS 140 200 µA 0.1 µA See Table 1 V 0.8 18 mV IOUT = 1 to 60 mA, (Note 2) 8 30 mV IOUT = 1 to 100 mA, (Note 2) 14 55 mV 120 200 mV VDROP Dropout Voltage IOUT = 60 mA, (Note 2) IOUT Continuous Output Current (Note 2) 100 mA IOUT(PULSE) Pulse Output Current 5 ms pulse, 12.5 % duty cycle, (Note 2) 130 mA RR Ripple Rejection f = 1 kHz, CL = 4.7 µF, CN = 0.1 µF, VIN = VOUT(TYP) + 2 V, VR = 200 mVrms, IOUT = 10 mA, (Notes 3,4) 70 dB VNO Output Noise Voltage 400 Hz ≤ f ≤ 80 kHz, CL = 4.7 µF, CN = 0.01 µF, VIN = VOUT(TYP) + 2 V, IOUT = 10 mA, (Notes 3,4) 30 µVrms Vref Noise Bypass Terminal Voltage 1.25 V ∆VOUT /∆T Temperature Coefficient 25 ppm/° C IOUT = 10 mA CONTROL TERMINAL SPECIFICATIONS ICONT Control Current VCONT = 1.8 V, Output ON VCONT(ON) Control Voltage ON Output ON VCONT(OFF) Control Voltage OFF Output OFF 1.2 4 1.5 µA V 0.35 V Note 1: Power dissipation is 600 mW when mounted as recommended. Derate at 4.8 mW/°C for operation above 25 °C. Note 2: Refer to “Definition of Terms.” Note 3: Ripple rejection and noise voltage are affected by the value and characteristics of the capacitor used. Note 4: Output noise voltage can be reduced by connecting a capacitor to the noise bypass terminal. Gen. Note: Parameters with min. or max. values are 100% tested at TA = 25 °C. Gen. Note: Exceeding the “Absolute Maximum Ratings” can damage the device. Page 2 March 1999 TOKO, Inc. TK111xxM ABSOLUTE MAXIMUM RATINGS TK111xxMIL (VOUT ≥ 2.4 V) Supply Voltage ......................................................... 15 V Control Terminal Voltage ......................................... 12 V Noise Bypass Terminal Voltage ................................. 5 V Power Dissipation (Note 1) ................................ 600 mW Reverse Bias ............................................................ 10 V Storage Temperature Range ................... -55 to +150 °C Operating Temperature Range ................... -40 to +85 °C Operating Voltage Range ............................... 2.0 to 12 V Junction Temperature ........................................... 150 °C Lead Soldering Temperature (10 s) ...................... 235 °C TK111xxMIL ELECTRICAL CHARACTERISTICS Test conditions: VIN = VOUT(TYP) + 1 V, TA = -40 to +85 °C, unless otherwise specified. SYMBOL PARAMETER TEST CONDITIONS IQ Quiescent Current IOUT = 0 mA, Excluding ICONT ISTBY Standby Current VIN = 6 V, Output OFF VOUT Output Voltage IOUT = 10 mA, VIN = VOUT(TYP) + 1 V Line Reg Line Regulation VIN = VOUT(TYP) + 1 V to VOUT(TYP) + 6 V, (Note 2) Load Reg Load Regulation MIN TYP MAX UNITS 140 200 µA 0.2 µA See Table 2 V 0.8 18 mV IOUT = 1 to 60 mA, (Note 2) 8 30 mV IOUT = 1 to 100 mA, (Note 2) 14 55 mV 120 200 mV VDROP Dropout Voltage IOUT = 60 mA, (Note 2) IOUT Continuous Output Current (Note 2) 100 mA IOUT(PULSE) Pulse Output Current 5 ms pulse, 12.5 % duty cycle, (Note 2) 130 mA RR Ripple Rejection f = 1 kHz, CL = 4.7 µF, CN = 0.1 µF, VIN = VOUT(TYP) + 2 V, VR = 200 mVrms, IOUT = 10 mA, (Notes 3,4) 70 dB VNO Output Noise Voltage 400 Hz ≤ f ≤ 80 kHz, CL = 4.7 µF, CN = 0.01 µF, VIN = VOUT(TYP) + 2 V, IOUT = 10 mA, (Notes 3,4) 30 µVrms Vref Noise Bypass Terminal Voltage 1.25 V ∆VOUT /∆T Temperature Coefficient 25 ppm/° C IOUT = 10 mA CONTROL TERMINAL SPECIFICATIONS ICONT Control Current VCONT = 1.8 V, Output ON VCONT(ON) Control Voltage ON Output ON VCONT(OFF) Control Voltage OFF Output OFF 1.2 6 1.5 µA V 0.35 V Note 1: Power dissipation is 600 mW when mounted as recommended. Derate at 4.8 mW/°C for operation above 25 °C. Note 2: Refer to “Definition of Terms.” Note 3: Ripple rejection and noise voltage are affected by the value and characteristics of the capacitor used. Note 4: Output noise voltage can be reduced by connecting a capacitor to the noise bypass terminal. Gen. Note: Parameters with min. or max. values are 100% tested at TA = 25 °C. Gen. Note: Exceeding the “Absolute Maximum Ratings” can damage the device. March 1999 TOKO, Inc. Page 3 TK111xxM TK111xxMCL ELECTRICAL CHARACTERISTICS TABLE 1 Output Voltage 2.0 V 2.1 V 2.2 V 2.3 V 2.4 V 2.5 V 2.7 V 2.8 V 2.9 V 3.0 V 3.1 V 3.2 V 3.3 V 3.4 V 3.5 V Page 4 Voltage Code 20 21 22 23 24 25 27 28 29 30 31 32 33 34 35 VOUT(MIN) VOUT(MAX) 1.940 V 2.040 V 2.140 V 2.240 V 2.340 V 2.440 V 2.640 V 2.740 V 2.840 V 2.940 V 3.038 V 3.136 V 3.234 V 3.332 V 3.430 V 2.060 V 2.160 V 2.260 V 2.360 V 2.460 V 2.560 V 2.760 V 2.860 V 2.960 V 3.060 V 3.162 V 3.264 V 3.366 V 3.468 V 3.570 V Test Voltage 3.0 V 3.1 V 3.2 V 3.3 V 3.4 V 3.5 V 3.7 V 3.8 V 3.9 V 4.0 V 4.1 V 4.2 V 4.3 V 4.4 V 4.5 V Output Voltage 3.6 V 3.7 V 3.8 V 3.9 V 4.0 V 4.1 V 4.2 V 4.3 V 4.4 V 4.5 V 4.6 V 4.7 V 4.8 V 4.9 V 5.0 V Voltage Code 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 VOUT(MIN) VOUT(MAX) 3.528 V 3.626 V 3.724 V 3.822 V 3.920 V 4.018 V 4.116 V 4.214 V 4.312 V 4.410 V 4.508 V 4.606 V 4.704 V 4.802 V 4.900 V 3.672 V 3.774 V 3.876 V 3.978 V 4.080 V 4.182 V 4.284 V 4.386 V 4.488 V 7.590 V 4.692 V 4.794 V 4.896 V 4.998 V 5.100 V Test Voltage 4.6 V 4.7 V 4.8 V 4.9 V 5.0 V 5.1 V 5.2 V 5.3 V 5.4 V 5.5 V 5.6 V 5.7 V 5.8 V 5.9 V 6.0 V March 1999 TOKO, Inc. TK111xxM TK111xxMIL ELECTRICAL CHARACTERISTICS TABLE 2 Test Conditions: VIN = VOUT(TYP) + 1 V, IOUT = 30 mA, unless otherwise specified. Output Voltage Voltage Code 2.4 V 2.5 V 2.7 V 2.8 V 2.9 V 3.0 V 3.1 V 3.2 V 3.3 V 3.4 V 3.5 V 3.6 V 3.7 V 3.8 V 3.9 V 4.0 V 4.1 V 4.2 V 4.3 V 4.4 V 4.5 V 4.6 V 4.7 V 4.8 V 4.9 V 5.0 V 24 25 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 March 1999 TOKO, Inc. Room Temp. Range (TA = 25 °C) VOUT(MIN) VOUT(MAX) 2.340 V 2.440 V 2.640 V 2.740 V 2.840 V 2.940 V 3.038 V 3.136 V 3.234 V 3.332 V 3.430 V 3.528 V 3.626 V 3.724 V 3.822 V 3.920 V 4.018 V 4.116 V 4.214 V 4.312 V 4.410 V 4.598 V 4.696 V 4.794 V 4.892 V 4.900 V 2.460 V 2.560 V 2.760 V 2.860 V 2.960 V 3.060 V 3.162 V 3.264 V 3.366 V 3.468 V 3.570 V 3.672 V 3.774 V 3.876 V 3.988 V 4.080 V 4.182 V 4.284 V 4.366 V 4.488 V 4.590 V 4.692 V 4.794 V 4.896 V 4.998 V 5.100 V Full Temp. Range (TA = -40 to +85 °C) VOUT(MIN) VOUT(MAX) 2.305 V 2.405 V 2.605 V 2.705 V 2.805 V 2.905 V 3.007 V 3.104 V 3.201 V 3.298 V 3.395 V 3.492 V 3.589 V 3.686 V 3.783 V 3.880 V 3.977 V 4.074 V 4.171 V 4.268 V 4.365 V 4.462 V 4.559 V 4.656 V 4.753 V 4.850 V 2.495 V 2.595 V 2.795 V 2.895 V 2.995 V 3.095 V 3.193 V 3.296 V 3.400 V 3.502 V 3.605 V 3.708 V 3.811 V 3.914 V 4.017 V 4.120 V 4.223 V 4.326 V 4.429 V 4.532 V 4.635 V 4.738 V 4.841 V 4.944 V 5.047 V 5.150 V Page 5 TK111xxM TEST CIRCUIT VIN VIN IIN VOUT CIN 1 µF CONT CL 2.2 µF TANTALUM IOUT NOISE BYPASS CN = 0.0047 µF ICONT VCONT TYPICAL PERFORMANCE CHARACTERISTICS TA = 25 °C, unless otherwise specified. LOAD REGULATION OUTPUT VOLTAGE VS. INPUT VOLTAGE SHORT CIRCUIT CURRENT VOUT TYPICAL VOUT (25 mV/ DIV) VOUT (5 mV/ DIV) 5 4 VOUT (V) VOUT TYPICAL 3 2 IOUT = 0 mA IOUT = 30 mA IOUT = 60 mA IOUT = 90 mA 1 0 50 100 0 150 IOUT (mA) IOUT (mA) LINE REGULATION DROPOUT VOLTAGE VS. OUTPUT CURRENT VDROP (mV) VOUT (50 mV/ DIV) VOUT TYPICAL 300 0 10 -100 8 -200 -300 VIN (V) Page 6 20 6 4 2 -500 10 VIN = VOUT VIN (V) (50 mV/ DIV) GROUND CURRENT VS. OUTPUT CURRENT -400 0 0 IGND (mA) 0 0 100 IOUT (mA) 200 0 0 75 150 IOUT (mA) March 1999 TOKO, Inc. TK111xxM TYPICAL PERFORMANCE CHARACTERISTICS (CONT.) TA = 25 °C, unless otherwise specified. REVERSE BIAS CURRENT (VIN = 0 V) STANDBY CURRENT (OFF MODE) VS. INPUT VOLTAGE 500 QUIESCENT CURRENT (ON MODE) VS. INPUT VOLTAGE 100 IOUT = 0 mA 2 300 200 IQ (mA) ISTBY (pA) IREV (µA) 400 50 VOUT = 3 V 1 100 0 0 10 0 0 20 10 VREV (V) CONTROL CURRENT VS. CONTROL VOLTAGE 10 2 VOUT 0 0 20 VIN (V) GROUND CURRENT DROPOUT VOLTAGE IOUT = 60 mA VDROP (mV) IGND (mA) ICONT (µA) 200 4 1 IOUT = 30 mA IOUT = 100 mA IOUT = 60 mA 100 IOUT = 30 mA 2 1 2 3 4 0 -50 5 50 0 -50 100 0 50 100 VCONT (V) TA (°C) TA (°C) CONTROL CURRENT VCONT (VOUT, ON POINT) MAXIMUM OUTPUT CURRENT RCONT = 0 Ω 2 10 VOUT = 2.7 V OR ABOVE 260 VCONT = 5 V VCONT (V) 8 ICONT (µA) 0 6 4 IOUT (mA) 0 0 10 VIN (V) 8 6 5 1 VCONT = 1.8 V 250 240 230 2 220 0 -50 0 50 TA (°C) March 1999 TOKO, Inc. 100 0 -50 0 50 TA (°C) 100 -50 0 50 100 TA (°C) Page 7 TK111xxM TYPICAL PERFORMANCE CHARACTERISTICS (CONT.) TA = 25 °C, unless otherwise specified. RIPPLE REJECTION 0 10 -20 2.8 V 0 3.0 V 250 IOUT = 30 mA -40 CL = 4.7 µF, CN = 0.1 µF -60 -20 -80 IOUT = 60 mA 200 CL = 2.2 µF, CN = .01 µF -10 CL = 2.2 µF 150 CL = 3.3µF 100 CL = 10 µF -30 -50 0 50 100 50 CL = 4.7 µF, CN = 1.0 µF -100 0.01 1 10 0 1 pF 100 TA (°C) f (kHz) NOISE SPECTRUM LINE VOLTAGE STEP RESPONSE 0 10 -100 0 500 k 1M CN = 0.001 µF 0 100 200 0.1 µF .1 IOUT CL = 2.2 µF CN = 0.01 µF 1 OR 5 mA 1 TO 100 mA CN = 0.01 µF TIME (µs) f (Hz) 100 mA VOUT +1 V SPECTRUM ANALYZER BACKGROUND NOISE 1000 LOAD CURRENT STEP RESPONSE 1 VOUT (50 mV/ DIV) CL = 3.3 µF, CN = 0.1 µF VIN VOUT (10 mV/ DIV) CL = 3.3 µF, CN = NONE 100 CN VOUT +2 V -50 dB OUTPUT NOISE LEVEL VS. CN NOISE (µV) 20 RR (dB) ∆VOUT (mV) OUTPUT VOLTAGE VARIATION 5 TO 100 mA 300 400 0 200 400 600 800 TIME (µs) LOAD CURRENT STEP RESPONSE 2 IOUT VOUT (10 mV/ DIV) 50 mA CN = 0.01 µF 0 mA CL = 4.7 µF CL = 2.2 µF CL = 10 µF CL = 47 µF 0 2 4 6 8 TIME (ms) Page 8 March 1999 TOKO, Inc. TK111xxM DEFINITION AND EXPLANATION OF TECHNICAL TERMS OUTPUT VOLTAGE (VOUT) the ground terminal under no load conditions (IOUT = 0 mA). The output voltage is specified with VIN = (VOUT(TYP) + 1 V) and IOUT = 10 mA. GROUND CURRENT DROPOUT VOLTAGE (VDROP) The dropout voltage is the difference between the input voltage and the output voltage at which point the regulator starts to fall out of regulation. Below this value, the output voltage will fall as the input voltage is reduced. It is dependent upon the load current and the junction temperature. OUTPUT CURRENT (IOUT(MAX)) The rated output current is specified under the condition where the output voltage drops 0.3 V below the value specified with IOUT = 10 mA. The input voltage is set to VOUT +1 V, and the current is pulsed to minimize temperature effect. CONTINUOUS OUTPUT CURRENT (IOUT) Ground current is the current which flows through the ground pin(s). It is defined as IIN - IOUT, excluding control current. RIPPLE REJECTION RATIO (RR) Ripple rejection is the ability of the regulator to attenuate the ripple content of the input voltage at the output. It is specified with 200 mVrms, 1 kHz superimposed on the input voltage, where VIN = VOUT + 2 V. The output decoupling capacitor is set to 4.7 µF, the noise bypass capacitor is set to 0.01 µF, 0.1 µF, 1.0 µF and the load current is set to 10 mA. Ripple rejection is the ratio of the ripple content of the output vs. the input and is expressed in dB. Example: 64 dB at CN = 0.01 µF, 70 dB at CN = 0.1 µF, 74 dB at CN = 1.0 µF SENSOR CIRCUITS Normal operating output current. This is limited by the package power dissipation. Overcurrent Sensor PULSE OUTPUT CURRENT (IOUT (PULSE)) The overcurrent sensor protects the device if the output is shorted to ground. Max pulse width 5 ms, Duty cycle 12.5%: pulse load only. Thermal Sensor LINE REGULATION (Line Reg) Line regulation is the ability of the regulator to maintain a constant output voltage as the input voltage changes. The line regulation is specified as the input voltage is changed from VIN = VOUT(TYP) + 1 V to VIN = VOUT(TYP) + 6 V. LOAD REGULATION (Load Reg) Load regulation is the ability of the regulator to maintain a constant output voltage as the load current changes. It is a pulsed measurement to minimize temperature effects with the input voltage set to VIN = VOUT(TYP) +1 V. The load regulation is specified under two output current step conditions of 1 mA to 60 mA and 1 mA to 100 mA. QUIESCENT CURRENT (IQ) The quiescent current is the current which flows through March 1999 TOKO, Inc. The thermal sensor protects the device if the junction temperature exceeds the safe value (Tj = 150 °C). This temperature rise can be caused by extreme heat, excessive power dissipation caused by large output voltage drops, or excessive output current. The regulator will shut off when the temperature exceeds the safe value. As the junction temperature decreases, the regulator will begin to operate again. Under sustained fault conditions, the regulator output will oscillate as the device turns off then resets. Damage may occur to the device under extreme fault conditions. Reverse Voltage Protection Reverse voltage protection prevents damage due to the output voltage being higher than the input voltage. This fault condition can occur when the output capacitor remains charged and the input is reduced to zero, or when an Page 9 TK111xxM DEFINITION AND EXPLANATION OF TECHNICAL TERMS (CONT.) REDUCTION OF OUTPUT NOISE Although the architecture of the Toko regulators is designed to minimize semiconductor noise, further reduction can be achieved by the selection of external components. The obvious solution is to increase the size of the output capacitor. A more effective solution would be to add a capacitor to the noise bypass terminal. The value of this capacitor should be 0.1 µF or higher (higher values provide greater noise reduction). Although stable operation is possible without the noise bypass capacitor, this terminal has a high impedance and care should be taken to avoid a large circuit area on the printed circuit board when the capacitor is not used. Please note that several parameters are affected by the value of the capacitors and bench testing is recommended when deviating from standard values. ON/OFF RESPONSE WITH CONTROL The turn-on time depends upon the value of the output capacitor and the noise bypass capacitor. The turn-on time will increase with the value of either capacitor. The graphs below show the relationship between turn-on time and load capacitance. If the value of these capacitors is reduced, the load and line regulation will suffer and the noise voltage will increase. If the value of these capacitors is increased, the turn on time will increase. OUTPUT VOLTAGE RESPONSE B (OFF→ON) ILOAD = 30 mA, CL = 2.2 µF VCONT external voltage higher than the input voltage is applied to the output side. CN = 0.33 µF CN = 0.1 µF CN = 0.47 µF CN = 0.68µF The TK111xxM has an active high control pin. The control pin requires over 1.8 V for operation and under 0.6 V for standby. For the range of 0.6 V < VCONT < 1.8 V, operation is undefined. If the control function is not used, connect the control pin to VIN. CN = 1.0 µF VOUT CONTROL FUNCTION 0 2 4 6 8 TIME (ms) OUTPUT VOLTAGE RESPONSE A (OFF→ON) VIN VCONT ILOAD = 30 mA, CN = 3300 pF SW CL = 0.68 µF CL = 0.47µF CL = 1.5 µF CN VOUT CL = 1.0 µF -5 5 15 25 35 45 TIME (µs) CONTROL FUNCTION Page 10 March 1999 TOKO, Inc. TK111xxM DEFINITION AND EXPLANATION OF TECHNICAL TERMS (CONT.) PACKAGE POWER DISSIPATION (PD) This is the power dissipation level at which the thermal sensor is activated. The IC contains an internal thermal sensor which monitors the junction temperature. When the junction temperature exceeds the monitor threshold of 150 °C, the IC is shut down. The junction temperature rises as the difference between the input power (VIN x IIN) and the output power (VOUT x IOUT) increases. The rate of temperature rise is greatly affected by the mounting pad configuration on the PCB, the board material, and the ambient temperature. When the IC mounting has good thermal conductivity, the junction temperature will be low even if the power dissipation is great. When mounted on the recommended mounting pad, the power dissipation of the SOT-23L-6 is increased to 600 mW. For operation at ambient temperatures over 25 °C, the power dissipation of the SOT-23L-6 device should be derated at 4.8 mW/°C. To determine the power dissipation for shutdown when mounted, attach the device on the actual PCB and deliberately increase the output current (or raise the input voltage) until the thermal protection circuit is activated. Calculate the power dissipation of the device by subtracting the output power from the input power. These measurements should allow for the ambient temperature of the PCB. The value obtained from PD /(150 °C - TA) is the derating factor. The PCB mounting pad should provide maximum thermal conductivity in order to maintain low device temperatures. As a general rule, the lower the temperature, the better the reliability of the device. The thermal resistance when mounted is expressed as follows: The range of usable currents can also be found from the graph below. (mW) 6 DPD 4 5 25 50 75 TA ( C) 150 Procedure: 1) 2) 3) 4) Find PD PD1 is taken to be PD x (~ 0.8 - 0.9) Plot PD1 against 25 °C Connect PD1 to the point corresponding to the 150 °C with a straight line. 5) In design, take a vertical line from the maximum operating temperature (e.g., 75 °C) to the derating curve. 6) Read off the value of PD against the point at which the vertical line intersects the derating curve. This is taken as the maximum power dissipation, DPD. 1.0 MOUNTED AS SHOWN 0.8 PD (mW) Tj = 0jA x PD + TA For Toko ICs, the internal limit for junction temperature is 150 °C. If the ambient temperature (TA ) is 25 °C, then: 3 PD 0.6 FREE AIR 0.4 0.2 150 °C = 0jA x PD + 25 °C 0jA = 125 °C/ PD 0 0 50 100 150 TA (°C) PD is the value when the thermal sensor is activated. A simple way to determine PD is to calculate VIN x IIN when the output side is shorted. Input current gradually falls as temperature rises. You should use the value when thermal equilibrium is reached. March 1999 TOKO, Inc. SOT-23L-6 POWER DISSIPATION CURVE Page 11 TK111xxM APPLICATION INFORMATION INPUT-OUTPUT CAPACITORS Linear regulators require an output capacitor in order to maintain regulator loop stability. This capacitor should be selected to ensure stable operation over the desired temperature and load range. The graphs below show the effects of capacitance value and Equivalent Series Resistance (ESR) on the stable operation area. 111xx CL ESR CL = 3.3 µF CL = 2.2 µF CL = 10 µF 1000 1000 1000 100 100 100 100 STABLE OPERATION AREA 10 STABLE OPERATION AREA 10 ESR (Ω) 10 ESR (Ω) 1000 ESR (Ω) ESR (Ω) CL = 1 µF STABLE OPERATION AREA 10 STABLE OPERATION AREA 1 1 1 1 0.1 0.1 0.1 0.1 0 .01 0 .01 0 .01 1 50 100 130 1 IOUT (mA) 50 100 130 0 .01 1 50 100 IOUT (mA) IOUT (mA) 130 1 50 100 130 IOUT (mA) In general, the capacitor should be at least 1 µF (aluminum electrolytic) and be rated for the actual ambient operating temperature range. The table below shows typical characteristics for several types and values of capacitance. Please note that the ESR varies widely depending upon manufacturer, type, size, and material. ESR Capacitance Aluminum Capacitor Tantalum Capacitor Ceramic Capacitor 1.0 µF 2.4 Ω 2.3 Ω 0.140 Ω 2.2 µF 2.0 Ω 1.9 Ω 0.059 Ω 3.3 µF 4.6 Ω 1.0 Ω 0.049 Ω 10 µF 1.4 Ω 0.5 Ω 0.025 Ω Note: ESR is measured at 10 kHz. Page 12 March 1999 TOKO, Inc. TK111xxM APPLICATION INFORMATION (CONT.) BOARD LAYOUT Copper pattern should be as large as possible. Power dissipation is 600 mW for the SOT-23L-6. A low ESR capacitor is recommended. For low temperature operation, select a capacitor with a low ESR at the lowest operating temperature to prevent oscillation, degradation of ripple rejection and increase in noise. The minimum recommended capacitance is 1.0 µF. VIN GND + VOUT + CONTROL NOISE BYPASS SOT-23L-6 BOARD LAYOUT March 1999 TOKO, Inc. Page 13 TK111xxM NOTES Page 14 March 1999 TOKO, Inc. TK111xxM NOTES March 1999 TOKO, Inc. Page 15 TK111xxM PACKAGE OUTLINE Marking Information SOT-23L-6 TK111xxM Product Code W TK11120M TK11121M TK11122M TK11123M TK11124M TK11125M TK11127M TK11128M TK11129M TK11130M TK11131M TK11132M TK11133M TK11134M TK11135M TK11136M TK11137M TK11138M TK11139M TK11140M TK11141M TK11142M TK11143M TK11144M TK11145M TK11146M TK11147M TK11148M TK11149M TK11150M Voltage Code 20 21 22 23 24 25 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 +0.15 - 0.05 0.4 6 5 0.1 M 0.6 4 e1 3.0 1.0 Marking Product Code Voltage Code 1 2 3 e 0.32 5 PL e 0.95 +0.15 - 0.05 0.1 e 0.95 M 0.95 3.5 e 0.95 Recommended Mount Pad +0.3 - 0.1 (3.4) 15 max 1.2 0.4 0.15 Dimensions are shown in millimeters Tolerance: x.x = ± 0.2 mm (unless otherwise specified) +0.15 - 0.05 0 - 0.1 1.4 max 0.3 2.2 + 0.3 3.3 Toko America, Inc. Headquarters 1250 Feehanville Drive, Mount Prospect, Illinois 60056 Tel: (847) 297-0070 Fax: (847) 699-7864 TOKO AMERICA REGIONAL OFFICES Midwest Regional Office Toko America, Inc. 1250 Feehanville Drive Mount Prospect, IL 60056 Tel: (847) 297-0070 Fax: (847) 699-7864 Western Regional Office Toko America, Inc. 2480 North First Street , Suite 260 San Jose, CA 95131 Tel: (408) 432-8281 Fax: (408) 943-9790 Eastern Regional Office Toko America, Inc. 107 Mill Plain Road Danbury, CT 06811 Tel: (203) 748-6871 Fax: (203) 797-1223 Semiconductor Technical Support Toko Design Center 4755 Forge Road Colorado Springs, CO 80907 Tel: (719) 528-2200 Fax: (719) 528-2375 Visit our Internet site at http://www.tokoam.com The information furnished by TOKO, Inc. is believed to be accurate and reliable. However, TOKO reserves the right to make changes or improvements in the design, specification or manufacture of its products without further notice. TOKO does not assume any liability arising from the application or use of any product or circuit described herein, nor for any infringements of patents or other rights of third parties which may result from the use of its products. No license is granted by implication or otherwise under any patent or patent rights of TOKO, Inc. Page 16 © 1999 Toko, Inc. All Rights Reserved March 1999 TOKO, Inc. IC-xxx-TK111M 0798O0.0K Printed in the USA