Electronic Components Datasheet Search |
|
PAM3102 Datasheet(PDF) 9 Page - Power Analog Micoelectronics |
|
PAM3102 Datasheet(HTML) 9 Page - Power Analog Micoelectronics |
9 / 11 page Application Information 9 Capacitor Selection and Regulator Stability Shutdown Input Operation Input-Output ( Dropout ) Voltage Current Limit and Short Circuit Protection Thermal considerations Similar to any low dropout regulator, the external capacitors used with the PAM3102 must be carefully selected for regulator stability and performance. Please note that the distance between C and the input pin of the PAM3102 should not exceed 0.5 inch. Ceramic capacitors a re suitable for t he PAM3102. Capacitors with larger values and lower ESR (equivalent series resistance) provide better PSRR and line-transient response. The PAM3102 is designed specifically to work with low ESR ceramic output capacitors in order to save space and improve performance. Using an output ceramic capacitor whose value is > The PAM3102 is shutdown by pulling the CE input low, and turned on by tying the CE input to VIN or leaving the CE input floating. A regulator's minimum input-output voltage differential (or dropout voltage) determines the lowest usable supply voltage. The PAM3102 has a typical 180mV dropout voltage. In battery- powered systems, this will determine the useful end-of-life battery voltage. The PAM3102 features a current limit, which monitors and controls the gate voltage of the pass transistor. The output current can be limited to 300mA by regulating the gate voltage. The PAM3102 also has a built-in short circuit current limit. Thermal protection limits power dissipation in the PA M3102. When the junction temperature exceeds 150°C, the OTP (Over Temperature Protection) starts the thermal shutdown and turns the pass transistor off. The pass transistor resumes operation after the junction temperature drops below 120°C. For c ontinuous operation, the junction temperature should be maintained below 125°C. The power dissipation is defined as: P = (V -V )*I +Vin*Ignd The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surrounding airflow and temperature difference between junction and ambient. The maximum power dissipation can be calculated by the following formula: Where T is the maximum allowable junction temperature 125°C,T i s t he ambient temperature and is the thermal resistance from the junction to the ambient. For example, as is 250°C/W for the SOT-23 package based on the standard JEDEC 51-3 for a single-layer thermal test board, the maximum power dissipation at TA =25°C can be calculated by following formula: P =(125°C-25°C)/250=0.4W SOT-23 It is also useful to calculate the junction temperature of the PAM3102 under a set of specific conditions. Suppose the input voltage V =3.3V, the output current I =300mA and the case temperature T =40°C measured by a thermalcouple during operation, the our power dissipation is defined as: P =(3.3V-2.8V)*150mA+(3.3V-1.8V) *150mA+3.3V*200 A 300mW And t he junction temperature T can b e calculated as follows: T= T T = 40°C+0.3W*250°C/W =40°C+75°C =115°C<T = 125°C For this application, T is lower than the absolute maximum operating junction temperature,125°C, so it is safe to use the PAM3102 in this configuration. IN DIN J(MAX) A JA D(MAX) IN O A D J JA A J J(MAX) J 2.2μF with ESR>5mΩ ensures stability. P = (T -T )/θ θ θ μ +P *θ D(MAX) J(MAX) A JA JA DJ ≌ A capacitor C of more than 1μF can be employed in the input pin, while there is no upper limit for the capacitance of C . IN IN OO PAM3102 Dual 150mA High PSRR Low-Dropout CMOS Regulator 09/2008 Rev 1.1 , Power Analog Microelectronics Inc www.poweranalog.com |
Similar Part No. - PAM3102 |
|
Similar Description - PAM3102 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |