Moteur de recherche de fiches techniques de composants électroniques |
|
TC2117-1.8VDBTR Fiches technique(PDF) 7 Page - Microchip Technology |
|
TC2117-1.8VDBTR Fiches technique(HTML) 7 Page - Microchip Technology |
7 / 18 page © 2006 Microchip Technology Inc. DS21665C-page 7 TC2117 4.0 DETAILED DESCRIPTION The TC2117 is a precision, positive output LDO. Unlike bipolar regulators, the TC2117 supply current does not increase proportionally with load current. In addition, VOUT remains stable and within regulation over the entire 0 mA to 800 mA operating load range. FIGURE 4-1: TYPICAL APPLICATION CIRCUIT 4.1 Output Capacitor A 1 µF (min) capacitor from VOUT to ground is required. The output capacitor should have an effective series resistance of 0.2 Ω to 10Ω. A 1 µF capacitor should be connected from VIN to GND if there is more than 10 inches of wire between the regulator and the AC filter capacitor, or if a battery is used as the power source. Aluminum electrolytic or tantalum capacitor types can be used. (Since many aluminum electrolytic capacitors freeze at approximately -30°C, solid tantalums are recommended for applications operating below -25°C.) When operating from sources other than batteries, supply noise rejection and transient response can be improved by increasing the value of the input and output capacitors and employing passive filtering techniques. 4.2 Thermal Considerations 4.2.1 THERMAL SHUTDOWN Integrated thermal protection circuitry shuts the regula- tor off when die temperature exceeds 160°C. The regulator remains off until the die temperature drops to approximately 150°C. 4.2.2 POWER DISSIPATION The amount of power the regulator dissipates is prima- rily a function of input and output voltage, and output current. The following equation is used to calculate worst case actual power dissipation: EQUATION 4-1: The maximum allowable power dissipation (Equation 4-2) is a function of the maximum ambient temperature (TAMAX), the maximum allowable die temperature (+125°C) and the thermal resistance from junction-to-air ( θJA). EQUATION 4-2: Table 4-1 shows various values of θJA for the TC2117 mounted on a 1/16 inch, 2-layer PCB with 1 oz. copper foil. TABLE 4-1: THERMAL RESISTANCE GUIDELINES FOR TC2117 IN 3-PIN SOT-223 PACKAGE C1 1µF Battery TC2117 VIN VOUT C2 1µF GND VOUT Copper Area (Topside)* Copper Area (Backside) Board Area Thermal Resistance 2500 sq mm 2500 sq mm 2500 sq mm 45°C/W 1000 sq mm 2500 sq mm 2500 sq mm 45°C/W 225 sq mm 2500 sq mm 2500 sq mm 53°C/W 100 sq mm 2500 sq mm 2500 sq mm 59°C/W 1000 sq mm 1000 sq mm 1000 sq mm 52°C/W 1000 sq mm 0 sq mm 1000 sq mm 55°C/W * Tab of device attached to topside copper. Where: VINMAX VOUTMIN ILOADMAX PD = Worst-case actual power dissipation = Minimum regulator output voltage = Maximum output (load) current = Maximum voltage on VIN PD VINMAX VOUTMIN – ()I LOADMAX = PDMAX = (TJMAX – TAMAX) θJA Where all terms are previously defined. |
Numéro de pièce similaire - TC2117-1.8VDBTR |
|
Description similaire - TC2117-1.8VDBTR |
|
|
Lien URL |
Politique de confidentialité |
ALLDATASHEET.FR |
ALLDATASHEET vous a-t-il été utile ? [ DONATE ] |
À propos de Alldatasheet | Publicité | Contactez-nous | Politique de confidentialité | Echange de liens | Fabricants All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |