Electronic Components Datasheet Search |
|
EL2227CYZ Datasheet(PDF) 11 Page - Intersil Corporation |
|
EL2227CYZ Datasheet(HTML) 11 Page - Intersil Corporation |
11 / 14 page 11 FN7058.4 September 14 ,2010 Applications Information Product Description The EL2227 is a dual voltage feedback operational amplifier designed especially for DMT ADSL and other applications requiring very low voltage and current noise. It also features low distortion while drawing moderately low supply current and is built on Elantec's proprietary high-speed complementary bipolar process. The EL2227 use a classical voltage-feedback topology, which allows them to be used in a variety of applications where current-feedback amplifiers are not appropriate because of restrictions placed upon the feedback element used with the amplifier. The conventional topology of the EL2227 allows, for example, a capacitor to be placed in the feedback path, making it an excellent choice for applications such as active filters, sample-and-holds, or integrators. ADSL CPE Applications The low noise EL2227 amplifier is specifically designed for the dual differential receiver amplifier function with ADSL transceiver hybrids, as well as other low-noise amplifier applications. A typical ADSL CPE line interface circuit is shown in Figure 38. The EL2227 is used in receiving DMT down stream signal. With careful transceiver hybrid design and the EL2227 1.9nV/ √Hz voltage noise and 1.2pA/√Hz current noise performance, -140dBm/Hz system background noise performance can be easily achieved. Disable Function The EL2227 is in the standard dual amplifier package without the enable/disable function. A simple way to implement the enable/disable function is depicted in Figure 39. When disabled, both the positive and negative supply voltages are disconnected (see Figure 39). Power Dissipation With the wide power supply range and large output drive capability of the EL2227, it is possible to exceed the +150°C maximum junction temperatures under certain load and power supply conditions. It is therefore important to calculate the maximum junction temperature (TJMAX) for all applications to determine if power supply voltages, load conditions, or package type need to be modified for the EL2227 to remain in the safe operating area. These parameters are related in Equation 1: where: PDMAXTOTAL is the sum of the maximum power dissipation of each amplifier in the package (PDMAX) PDMAX for each amplifier can be calculated using Equation 2: where: TMAX = Maximum Ambient Temperature θJA = Thermal Resistance of the Package PDMAX = Maximum Power Dissipation of 1 Amplifier VS = Supply Voltage IMAX = Maximum Supply Current of 1 Amplifier VOUTMAX = Maximum Output Voltage Swing of the Application RL = Load Resistance To serve as a guide for the user, we can calculate maximum allowable supply voltages for the example of the video cable-driver below since we know that TJMAX = +150°C, TMAX = +75°C, ISMAX = 9.5mA, and the package θJAs are shown in Table 1. If we assume (for this example) that we are driving a back-terminated video cable, then the maximum average value (over duty-cycle) of VOUTMAX is 1.4V, and RL = 150Ω, giving the results seen in Table 1. FIGURE 38. TYPICAL LINE INTERFACE CONNECTION - + - + - + - + RECEIVE OUT - RECEIVE OUT + DRIVER INPUT RG RF RF RF R RIN R RIN RF ROUT ROUT LINE + LINE - RECEIVE AMPLIFIERS ZLINE - + 1µF 4.7µF 1µF +12V 1k 10k 10k 75k 1k 1k FIGURE 39. IMPLEMENTATION OF ENABLE/DISABLE FUNCTION TJMAX TMAX θJA PDMAXTOTAL × () + = (EQ. 1) PDMAX 2VS ISMAX VS ( VOUTMAX) VOUTMAX RL ---------------------------- × – + × × = (EQ. 2) EL2227 |
Similar Part No. - EL2227CYZ |
|
Similar Description - EL2227CYZ |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | 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 |