AMS1117-3.3

AMS1117 0 . 8 A LOW DROPOUT VOLTAGE REGULATOR Description Features The AMS1117 is a series of low dropout voltage  Low Dropout Voltage. regulators which can provide up to 0.8A of output  Load regulation: 0.5% Max. current. The AMS1117 is available in six fixed  Optimized for Low Voltage voltage, 1.2, 1.5, 1.8, 2.5, 3.3 and 5.0V. Additionally  On-chip thermal limiting. it is also available in adjustable version. On chip  Maximum Input Voltage : 18V precision trimming adjusts the reference/ output  Adjustable Output Voltage or Fixed 1.2V, voltage to within ± 2%. On-chip thermal limiting 1.5V, 1.8V, 2.5V, 3.3V,5V provides protection against any combination of  overload and ambient temperatures that would Standard SOT-223,TO-252 ,SOT89 Packages create excessive junction temperatures. Applications The AMS1117 series is available in SOT-223, TO-  Post Regulator for switching DC/DC Converter 252, SOT89 packages. A minimum of 10uF tantalum capacitor is required at the output to  High Efficiency Linear Regulator improve the transient response and stability.        Battery Chargers  PC Add on Card  Motherboard clock supplies  LCD Monitor r  Set-top Box Block Diagram         www.slkormicro.com       1 AMS1117 Pin Description Absolute Maximum Ratings Symbol VIN IOUT TJ   Description Input Voltage Max   18 DC Output Current Operating Junction Temperature Range Units V PD/(VIN-VOUT) mA -40 to 125 ℃ θ JA Thermal Resistance (SOT-223) 150 ℃/W θ JA Thermal Resistance (TO-252) 125 ℃/W θ JA Thermal Resistance (SOT89) 225 ℃/W PD Maximum Power Dissipation (SOT-223) 600 mW PD Maximum Power Dissipation (TO-252) 900 mW PD Maximum Power Dissipation (SOT89) 400 mW www.slkormicro.com 2 AMS1117 Electrical Characteristics (Vin = 11μF. www.slkormicro.com   5 AMS1117 Load Regulation When the adjustable regulator is used (Fig.2), the best load regulation is accomplished when the top of the resistor divider (R1) is connected directly to the output pin of the AMS1117. When so connected, RP is not multiplied by the divider ratio. For Fixed output version, the top of R1 is internally connected to the output and ground pins can be connected to low side of the load Figure 2. Best Load Regulation Using Adjustable Output Regulator Thermal Protection AMS1117 has thermal protection which limits junction temperature to 150 ℃ . However, device functionality is only guaranteed to a maximum junction temperature of +125℃. The power dissipation and junction temperature for AMS1117 in DPAK package are given by PD = (VIN – VOUT) * Iout TJUNCTION = TAMBIENT + (PD * θ JA) Note: TJUNCTION must not exceed 125℃  Thermal Consideration The AMS1117 series contain thermal limiting circuitry designed to protect itself from overtemperature conditions. Even for normal load conditions, maximum junction temperature ratings must not be exceeded. As mention in thermal protection section, we need to consider all sources of thermal resistance between junction and ambient. It includes junction-to case, case-to-heat-sink interface, and heat sink thermal resistance itself. Junction-to-case thermal resistance is specified from the IC junction to the bottom of the case directly below the die. Proper mounting is required to ensure the best possible thermal flow from this area of the package to the heat sink. The case of all devices in this series is electrically connected to the output. Therefore, if the case of the device must be electrically isolated, a thermally conductive spacer is recomme www.slkormicro.com   6 AMS1117 PACKAGE DESCRIPTION SOT-223 PACKAGE OUTLINE DIMENSIONS Dimensions ln Millimeters Dimensions ln lnches Symbol Min   Max Min Max A 1.520   1.800 0.060 0.071 A1 0.020   0.130 0.001 0.005 A2 1.500   1.700 0.059 0.067 b 0.660   0.840 0.026 0.033 c 0.230   0.350 0.009 0.014 D 6.450   6.850 0.254 0.270 D1 2.900   3.000 0.114 0.122 E 3.450   3.850 0.136 0.152 E1 6.830   7.070 0.269 0.278   e       0.091(BSC) e1 4.500   4.700 0.177 0.185 L 0.900   1.150 0.035 0.045 θ 0° 10° www.slkormicro.com   2.300（BSC） 7 0° 10 AMS1117 TO-252-2L PACKAGE OUTLINE DIMENSIONS Dimensions ln Millimeters Symbol Min   Max Min Max 2.400 0.087 0.094 A 2.200     A1 0.000   0.127 0.000 0.005 B 1.200   1.650 0.047 0.065 b 0.500   0.810 0.020 0.032 b1 0.700   0.900 0.028 0.035 c 0.460   0.580 0.018 0.023 c1 0.430   0.580 0.014 0.023 D 6.350   6.700 0.250 0.264 D1 5.200   5.400 0.205 0.213 E 5.400   6.200 0.213 0.244 e   2.300TYP     0.0901TYP e1 4.500   4.700 0.177 0.185 L1 9.500   9.900 0.374 0.390 L2 0.950   1.600 0.037 0.063 L3 0.700   1.100 0.028 0.043 L4 2.550   2.900 0.100 0.114 V   www.slkormicro.com   Dimensions ln lnches 3.80REF     8 0.150REF AMS1117 SOT89 PACKAGE OUTLINE DIMENSIONS Dimensions ln Millimeters Symbol Min   Max Min Max A 1.400   1.600 0.055 0.063 b 0.350   0.520 0.013 0.197 b1 0.400   0.580 0.016 0.023 c 0.350   0.450 0.014 0.018 D 4.400   4.600 0.173 0.181 D1 1.550   1.750 0.061 0.069 E 2.350   2.600 0.091 0.102 E1 3.720   4.530 0.146 0.178   e   1.500TYP     0.060TYP e1   3.000TYP     0.118TYP L www.slkormicro.com   Dimensions ln lnches 0.820   1.100 9 0.032 0.047