Motor de Búsqueda de Datasheet de Componentes Electrónicos |
|
ISL54065 Datasheet(PDF) 9 Page - Intersil Corporation |
|
ISL54065 Datasheet(HTML) 9 Page - Intersil Corporation |
9 / 15 page 9 FN6583.2 November 3, 2009 Detailed Description The ISL54065 is a bidirectional, dual single pole-double throw (SPDT) analog switch that offers precise switching from a single 1.8V to 6.5V supply with low ON-resistance (0.83 Ω) and high speed operation (t ON =55ns, tOFF = 18ns). The device is especially well suited for portable battery powered equipment due to its low operating supply voltage (1.8V), low power consumption (8nA), and a tiny 2.2x1.4mm µ TQFN package. The low ON-resistance and RON flatness provide very low insertion loss and signal distortion for applications that require signal switching with minimal interference by the switch. Supply Sequencing and Overvoltage Protection With any CMOS device, proper power supply sequencing is required to protect the device from excessive input currents which might permanently damage the IC. The ISL54065 contains ESD protection diodes on each pin of the IC (see Figure 9). These diodes connect to either a +Ring or -Ring for ESD protection. To prevent forward biasing the ESD diodes to the +Ring, V+ must be applied before any input signals, and the input signal voltages must remain between recommended operating range. If these conditions cannot be guaranteed, then precautions must be implemented to prohibit the current and voltage at the logic pin and signal pins from exceeding the maximum ratings of the switch. The following two methods can be used to provided additional protection to limit the current in the event that the voltage at a logic pin or switch terminal goes above the V+ rail. Logic inputs can be protected by adding a 1k Ω resistor in series with the logic input (see Figure 9). The resistor limits the input current below the threshold that produces permanent damage. This method is not acceptable for the signal path inputs. Adding a series resistor to the switch input defeats the purpose of using a low rON switch. Connecting external Schottky diodes to the signal pins will shunt the fault current to the V+ supply instead of through the internal ESD diodes thereby protecting the switch. These Schottky diodes must be sized to handle the expected fault current. Power-Supply and By-Pass Considerations The ISL54065 construction is typical of most single supply CMOS analog switches, in that they have two supply pins: V+ and GND. V+ and GND drive the internal CMOS switches and set their analog voltage limits. Unlike switches with a 5.5V maximum supply voltage, the ISL54065’s 6.5V maximum supply voltage provides plenty of head room for the 10% tolerance of 5V supplies due to overshoot and noise spikes. The minimum recommended supply voltage is 1.8V. It is important to note that the input signal range, switching times, and ON-resistance degrade at lower supply voltages. Refer to “Electrical Specifications” tables, beginning on page 3, and “Typical Performance Curves”, beginning on page 11, for details. V+ and GND also power the internal logic and level shifters. The level shifters convert the input logic levels to V+ and GND signals levels to drive the analog switch gate terminals. A high frequency decoupling capacitor placed as close to the V+ and GND pin as possible is recommended for proper operation of the switch. A value of 0.1µF is highly recommended. Negative Signal Swing Capability The ISL54065 contains circuitry that allows the analog switch signal to swing below ground. The device has an analog signal range of 6.5V below V+ up to the V+ rail (see Figure 16) while maintaining low rON performance. For example, if V+ = 5V, then the analog input signal range is from -1.5V to +5V. If V+ = 2.7V then the range is from -3.8V to +2.7V. Click and Pop Operation The ISL54065 contains circuitry that prevents audible click and pop noises that may occur when audio sources are powered on or off. Single supply audio sources are biased at a DC offset that can generate transients during power on/off. A DC blocking capacitor is needed to remove the DC bias at the speaker load. For 32 Ω headphones, a 220µF capacitor is typically used to preserve the audio bandwidth. The power GND VCOMx VNCx V+ LOGIC INPUTS VNOx -RING +RING CLAMP 1k Ω FIGURE 9. OVERVOLTAGE PROTECTION ISL54065 |
Número de pieza similar - ISL54065 |
|
Descripción similar - ISL54065 |
|
|
Enlace URL |
Política de Privacidad |
ALLDATASHEET.ES |
¿ALLDATASHEET es útil para Ud.? [ DONATE ] |
Todo acerca de Alldatasheet | Publicidad | Contáctenos | Política de Privacidad | Intercambio de Enlaces | Lista de Fabricantes 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 |