TS2931 series 100mA Ultra Low Dropout Positive Voltage Regulator Pin assignment 1. Output 2. Ground 3. Input Pin assignment 1. Output 2. Gnd 3. Gnd 4. Feedback 5. Shutdown 6. Gnd 7. Gnd 8. Input Input Voltage Range up to 30V Output Current up to 100mA General Description The TS2931 voltage regulator features a very low quiescent current of 1mA or less when supplying 10mA loads. This unique characteristic and the extremely low in-put-output differential required for proper regulation (0.2V for output currents of 10mA) make the TS2931 the ideal regulator for standby power systems. Applications include memory standby circuits, CMOS and other low power processor power supplies as well as systems demanding as much as 100mA of output current. Designed originally for automotive applications, the TS2931 and all regulated circuitry are protected from reverse battery installations or 2 battery jumps. During line transients, such as a load dump (60V) when the input voltage to the regulator can momentarily exceed the specified maximum operating voltage, the regulator will automatically shut down to protect both internal circuits and the load. The TS2931 can not be harmed by temporary mirror-image insertion. Familiar regulator features such as short circuit and thermal overload protection are also provided. Fixed output of 5V is available in the popular TO-92 and SOT-89 package. An adjustable output version, with on/off switch, is available in SOP-8 package. Features Application Very low quiescent current Battery powered systems Output current in excess of 100mA Portable instrumentation Input-Output differential less than 0.6V Avionics Reverse battery protection Automotive Electronics Unregulated DC input can withstand +60V positive SMPS Post-Regulator transients and -20V reverse battery Voltage Reference Short circuit protection Portable/Palm top / Notebook computers Internal thermal overload protection Portable consumer equipment Available as adjustable with TTL compatible switch Radio control system 100% electrical burn-in in thermal limit Available in plastic SOP-8, TO-92, SOT-89 package Ordering Information Part No. TS2931CTxx TS2931CSxx Operating Temp. (Ambient) -20 ~ +85 oC Package TO-92 SOP-8 Note: Where xx denotes voltage option, available are 8.0V, 8.5V, 9.0V, 10V, 12V, 15V, 5.0V, 3.3V and adjustable. Contact factory for additional voltage options. TS2931 series 1-5 2004/12 rev. A Absolute Maximum Rating Input Supply Voltage Vin - 20 ~ +35 V Power Dissipation Pd Internally Limited W Operating Junction Temperature Range TJ - 55 ~ +150 o C C C Storage Temperature Range TSTG -65 ~ +150 o Lead Temperature (Soldering 5 second) TSTG 260 o Electrical Characteristics(VIN=14V,Io=100uA, TJ=25℃(Note 1), Co=100µF(unless otherwise specified) Parameter Output Voltage (Fix Type) Input Supply Voltage Line Regulation Load Regulation Dropout Voltage Ground Current Conditions -20℃≤Tj ≤85℃ Full operating temperature Io =100uA ~ 100mA, Tj ≤Tj max 13V≤VIN≤16V 5mA≤Io≤100mA Io=10mA Io=100mA Io=100uA Io=10mA Io=100mA Min. Typ. Max. ---- --4 14 60 300 0.1 0.9 8 1.015|Vo| 1.02|Vo| 1.025|Vo| 26 30 50 200 600 0.15 1.5 12 0.985|Vo| 0.98|Vo| 0.975|Vo| ----- Vo Units V mV mV V mA Current Linit Vout=0 -- 160 200 mA Output Noise Voltage 10Hz-100KHz, COUT=100µF -- 500 -- uVRMS Ripple Rejection Ratio Io =10mA, fo=120Hz 60 -- -- dB 1.21 1.185 1.235 -- 1.26 1.285 V -- 20 40 nA -- -- -- nA/℃ -- 50 -- ppm/℃ Adjustable Type Only Reference Voltage Vout = 3V, Io≤100mA, R1=27K Full Operation Temperature Feedback Pin Bias Current Feedback Pin Bias Current Temperature Coefficient Reference Voltage Temperature Cofficient Shutdown Input 1.3 0.7 V --30 50 Shutdown Pin Input Current -uA 450 600 Regulator Output Current in Shutdown -3 10 Note 1: Output or reference voltage temp. coefficients defined as the worst case voltage change divided by the total temp. range. Note 2: Regulations is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects is covered under the specification for thermal regulation. Note 3: Line regulation is tested at 125℃for IL=1mA, For IL=100µA and TJ=125℃. Note 4: Dropout voltage is defined as the input to output differential at which the output voltage drops 2％ below it’s nominal value measured at 1V differential. Note 5: Ground pin current is the regulator quiescent current. The total current drawn form the source is the sum of the ground pin current and output load current. Note 6: Thermal regulation is the change in output voltage at a time T after a change in power dissipation, excluding load or line regulation effects. Specifications are for a 50mA load pulse (1.25W) for T=10ms. Note 7: Vref ≦Vout ≦(Vin-1V), 2.3V≦Vin≦26V, 100µA≦IL≦100mA, TJ≦TJMAX Note 8: Vshutdown ≧2V, Vin≦26V, Vout=0V Input Logic Voltage TS2931 series Low (Regulator ON) High (Regulator OFF) Vs=2.4V Vs=26V 2-5 -2 2004/12 rev. A Application Hints One of the distinguishing factors of the TS2931 series regulators is the requirement of an output capacitor for device stability. The value required varies greatly depending upon the application circuit and other factors. Thus some comments on the characteristics of both capacitors and the regulator are in order. High frequency characteristics of electrolytic capacitors depend greatly on the type and even the manufacturer. As a result, a value of capacitance that works well with the TS2931 for one brand or type may not necessary be sufficient with an electrolytic of different origin. Sometimes actual bench testing, as described later, will be the only means to determine the proper capacitor and value. Experience has shown that, as a rule of thumb, the more expensive and higher quality electrolytic generally allows a smaller value for regulator stability. As an example, while a high-quality 100 F aluminum electrolytic covers all general application circuits, similar stability can be obtained with a tantalum electrolytic of only 47uF. This factor of two can generally be applied to any special application circuit also. Another critical characteristic of electrolytic is their performance over temperature. While the TS2931 is designed to operate to -20℃, the same is not always true with all electrolytic (hot is generally not a problem). The electrolyte in many aluminum types will freeze around -250℃, reducing their effective value to zero. Since the capacitance is needed for regulator stability, the natural result is oscillation (and lots of it) at the regulator output. For all application circuits where cold operation is necessary, the output capacitor must be rated to operate at the minimum temperature. By coincidence, worst-case stability for the TS2931 also occurs at minimum temperatures. As a result, in applications where the regulator junction temperature will never be less than 25℃, the output capacitor can be reduced approximately by a factor of two over the value needed for the entire temperature range. To continue our example with the tantalum electrolytic, a value of only 22uF would probably thus suffice. For high-quality aluminum, 47uF would be adequate in such an application. Another regulator characteristic that is noteworthy is that stability decreases with higher output currents. This sensible fact has important connotations. In many applications, the TS2931 is operated at only a few milliamps of output current or less. In such a circuit, the output capacitor can be further reduced in value. As a rough estimation, a circuit that is required to deliver a maximum of 10mA of output current from the regulator would need an output capacitor of only half the value compared to the same regulator required to deliver the full output current of 100mA. If the example of the tantalum capacitor in the circuit rated at 25℃ junction temperature and above were continued to include a maximum of 10mA of output current, then the 22uF output capacitor could be reduced to only 10uF. In the case of the TS2931CS adjustable regulator in SOP-8 package, the minimum value of output capacitance is a function of the output voltage. As a general rule, the value decreases with higher output voltages, since internal loop gain is reduced. At this point, the procedure for bench testing the minimum value of an output capacitor in a special application circuit should be clear. Since worst-case occurs at minimum operating temperatures and maximum operating currents, the entire circuit, including the electrolytic, should be cooled to the minimum temperature. The input voltage to the regulator should be maintained at 0.6V above the output to keep internal power dissipation and die heating to a minimum. Worst-case occurs just after input power is applied and before the die has had a chance to heat up. Once the minimum value of capacitance has been found for the brand and type of electrolytic in question, the value should be doubled for actual use to account for production variations both in the capacitor and the regulator. (All the values in this section and the remainder of the data sheet were determined in this fashion.) Definition of Terms Dropout Voltage: The input-output voltage differential at which the circuit ceases to regulate against further reduction in input voltage. Measured when the output voltage has dropped 100 mV from the nominal value obtained at 14V input, dropout voltage is dependent upon load current and junction temperature. Input Voltage: The DC voltage applied to the input terminals with respect to ground. Input-Output Differential: The voltage difference between the unregulated input voltage and the regulated output voltage for which the regulator will operate. Line Regulation: The change in output voltage for a change input voltage. The measurement is made under conditions of low dissipation or by using pulse techniques such that the average chip temperature is not significantly affected. Load Regulation: The change in output voltage for a change in load current at constant chip temperature. Output Noise Voltage: The rms AC voltage at the output, with constant load and no input ripple, measured over a specified frequency range. Quiescent Current: That part of the positive input current that does not contribute to the positive load current. The regulator ground lead current. Ripple Rejection: The ratio of the peak-to-peak input ripple voltage to the peak-to-peak output ripple voltage. TS2931 series 3-5 2004/12 rev. A Typical Application Circuit *Required if regulator is located far from power supply filter. **C2 must be at least 100uF to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible to the regulator. This capacitor must be rated over the same operating temperature range as the regulator. The equivalent series resistance (ESR) of this capacitor is critical; see curve. VOUT = Reference Voltage x Note: Using 27K for R1 will automatically compensate for errors in VOUT due to the input bias current of the ADJ pin (approximately 1uA) TS2931 series 4-5 2004/12 rev. A TO-92 Mechanical Drawing A DIM B E C H F A B C D E F G H TO-92 DIMENSION MILLIMETERS INCHES MIN MAX MIN MAX 4.30 4.70 0.169 0.185 4.30 4.70 0.169 0.185 14.30(typ) 0.563(typ) 0.43 0.49 0.017 0.019 2.19 2.81 0.086 0.111 3.30 3.70 0.130 0.146 2.42 2.66 0.095 0.105 0.37 0.43 0.015 0.017 G D SOP-8 Mechanical Drawing A DIM 9 16 B 1 P 8 G R C D TS2931 series M F K 5-5 A B C D F G K M P R SOP-8 DIMENSION MILLIMETERS INCHES MIN MAX MIN MAX 4.80 5.00 0.189 0.196 3.80 4.00 0.150 0.157 1.35 1.75 0.054 0.068 0.35 0.49 0.014 0.019 0.40 1.25 0.016 0.049 1.27 (typ) 0.05 (typ) 0.10 0.25 0.004 0.009 o o o 0 7 0 7o 5.80 6.20 0.229 0.244 0.25 0.50 0.010 0.019 2004/12 rev. A