データシートサーチシステム |
|
ILC7083AIM527X データシート(PDF) 7 Page - Fairchild Semiconductor |
|
ILC7083AIM527X データシート(HTML) 7 Page - Fairchild Semiconductor |
7 / 16 page ILC7083/ILC7084 REV. 1.0.9 1/28/03 7 Maximum Output Current The maximum output current available from the ILC7083/ ILC7084 is limited by the maximum package power dissipa- tion as well as the device’s internal current limit. For a given ambient temperature, TA, the maximum package power dissipation is given by: PD(MAX) = (TJ(MAX) – TA) / θJA where TJ(MAX) = 150°C is the maximum junction tempera- ture and θ JA = 333°C/W is the package thermal resistance. For example at TA = 85°C ambient temperature, the maxi- mum package power dissipation is; PD(MAX) = 195mW. The maximum output current can be calculated from the fol- lowing equation: IOUT(MAX) < PD(MAX) / (VIN – VOUT) For example at VIN = 6V, VOUT = 5V and TA = 85°C, the maximum output current is IOUT(MAX) < 195mA. At higher output current, the die temperature will rise and cause the thermal protection circuit to be enabled. Application Hints Figure 4 shows the typical application circuit for the ILC7083. Figure 4. Basic Application Circuit for Fixed Output Voltage Versions Input Capacitor An input capacitor CIN of value 1µF or larger should be con- nected from VIN to the main ground plane. This will help to filter supply noise from entering the LDO. The input capaci- tor should be connected as close to the LDO regulator input pin as is practical. Using a high-value input capacitor will offer superior line transient response as well as better power supply ripple rejection. A ceramic or tantalum capacitor may be used at the input of the LDO regulator. Note that there is a parasitic diode from the LDO regulator output to the input. If the input voltage swings below the reg- ulator’s output voltage by a couple of hundred millivolts then the regulator may be damaged. This condition must be avoided. In many applications a large value input capacitor, CIN, will hold VIN higher than VOUT and decay slower than VOUT when the LDO is powered off. Output Capacitor Selection Fairchild strongly recommends the use of low ESR (equivalent series resistance) ceramic capacitors for COUT and CNOISE. The ILC7083/ILC7084 is stable with low ESR capacitor (as low as zero Ω). The value of the output capacitor should be 1µF or higher. Either ceramic chip or a tantalum capacitor may be used at the output. Use of ceramic chip capacitors offer significant advantages over tantalum capacitors. A ceramic capacitor is typically cheaper than a tantalum capacitor, it usually has a smaller footprint, lower height, and lighter weight than a tantalum capacitor. Furthermore, unlike tantalum capacitors which are polarized and can be damaged if connected incorrectly, ceramic capacitors are non-polarized. Low value ceramic chip capacitors with X5R or X7R dielectric are available in the 100pF to 4.7µF range. Beware of using ceramic capaci- tors with Y5V dielectric since their ESR increases signifi- cantly at cold temperatures. Please see the table of recommended ceramic capacitors for use at the output of ILC7083/ILC7084. Note: If a tantalum output capacitor is used then for stable operation. We recommend a low ESR tantalum capacitor with maximum rated ESR at or below 0.4 Ω. Low ESR tanta- lum capacitors, such as the TPS series from AVX Corpora- tion (www.avxcorp.com) or the T495 series from Kemet (www.kemet.com) may be used. In applications where a high output surge current can be expected, use a high value but low ESR output capacitor for superior load transient response. The ILC7083/ILC7084 is stable with no load. Noise Bypass Capacitor In low noise applications, the self noise of the ILC7083 can be decreased further by connecting a capacitor from the noise bypass pin (pin 4) to ground (pin 2). The noise bypass pin is a high impedance node as such care should be taken in printed circuit board layout to avoid noise pick-up from external sources. Moreover, the noise bypass capacitor should have low leakage. Noise bypass capacitors with a value as low as 470pF may be used. However, for optimum performance, use a 0.01µF or larger, ceramic chip capacitor. Note that the turn on and turn off response of the ILC7083 is inversely proportional to the value of the noise bypass capacitor. For fast turn on and turn off, use a small value noise bypass capacitor. In applica- tions where exceptionally low output noise is not required, consider omitting the noise bypass capacitor altogether. ILC7083 V OUT V IN C OUT SOT23-5 C IN ON OFF 12 3 4 5 C NOISE |
同様の部品番号 - ILC7083AIM527X |
|
同様の説明 - ILC7083AIM527X |
|
|
リンク URL |
プライバシーポリシー |
ALLDATASHEET.JP |
ALLDATASHEETはお客様のビジネスに役立ちますか? [ DONATE ] |
Alldatasheetは | 広告 | お問い合わせ | プライバシーポリシー | リンク交換 | メーカーリスト 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 |