Os motores de busca de Datasheet de Componentes eletrônicos |
|
ISL5586FCM Folha de dados(PDF) 11 Page - Intersil Corporation |
|
ISL5586FCM Folha de dados(HTML) 11 Page - Intersil Corporation |
11 / 20 page 4-11 Power Dissipation The power dissipation equations for forward active operation also apply to the reverse active mode. Ringing Overview The Ringing mode (RNG, 100) provides linear amplification to support a variety of ringing waveforms. A programmable ring trip function provides loop supervision and auto disconnect upon ring trip. The device is designed to operate from the high battery during this mode. Architecture The SLIC provides linear amplification to the differential signal applied to the ringing inputs (VRSP,VRSM). The differential ringing gain of the device is 100V/V. The circuit model for the ringing path is shown in Figure 8. The voltage gain from the differential ringing input to the Tip output is 50V/V. The resistor ratios provide a gain of 10 and the current mirror provides a gain of 5. The voltage gain from the differential input to the Ring output is -50V/V. The equations for the Tip and Ring outputs during ringing are provided below. When the differential input signal is zero, the Tip and Ring amplifier outputs are centered at half battery. The device provides auto centering for easy implementation of sinusoidal ringing waveforms. Both AC and DC control of the Tip and Ring outputs is available during ringing. This feature allows for DC offsets as part of the ringing waveform. Ringing Input Terminals The differential terminals feature high input impedance which allows the use of low value capacitors for AC coupling the ring signal if necessary. The Ringing input is enabled only during the ringing mode, therefore a free running oscillator may be connected at all times. When operating from a battery of -100V, each amplifier, Tip and Ring, will swing a maximum of 95VP-P.Hence,the maximum differential signal swing between VRSP and VRSM to achieve full scale ringing is approximately 1.9VP-P. Logic Control Ringing patterns consist of silent and ringing intervals. The ringing to silent pattern is called the ringing cadence. During the silent portion of ringing, the device can be programmed to any other operating mode. The most likely candidates are low power standby or forward active. Depending on system requirements, the low or high battery may be selected. Loop supervision is provided with the ring trip detector. The ring trip detector senses the change in loop current when the phone is taken off hook. The loop detector full-wave rectifies the ringing current, which is then filtered with external components RRT and CRT. The resistor RRT sets the trip threshold and the capacitor CRT sets the trip response time. Most applications will require a trip response time less than 150ms. Three very distinct actions occur when the device detects a ring trip. First, the DET output is latched low. The latching mechanism eliminates the need for software filtering of the detector output. The latch is cleared when the operating mode is changed externally. Second, the Ringing inputs are disabled, removing the ring signal from the line. Third, the device is internally forced to the forward active mode. Power Dissipation The power dissipation during ringing is dictated mostly by the load driving requirements and the ringing waveform. The key to valid power calculations is the correct definition of average and RMS currents. The average current defines the high battery supply current. The RMS current defines the load current. The cadence provides a time averaging reduction in the peak power. The total power dissipation consists of ringing power, Pr, and the silent interval power, Ps. FIGURE 7. REVERSAL TIMING CONTROL CPOL POL I1 75k Ω I2 FIGURE 8. LINEAR RINGING MODEL TIP RING R/8 R R + - + - 5:1 20 20 + - VBH 2 VRSP VRSM R R 1.25R 1.25R V T V BH 2 ----------- 50 V DIF × () + = (EQ. 29) V R V BH 2 ----------- 50 V DIF × () – = (EQ. 30) P RNG P r t r t r t s + -------------- × P s t s t r t s + -------------- × + = (EQ. 31) ISL5586 |
Nº de peça semelhante - ISL5586FCM |
|
Descrição semelhante - ISL5586FCM |
|
|
Ligação URL |
Privacy Policy |
ALLDATASHEETPT.COM |
ALLDATASHEET é útil para você? [ DONATE ] |
Sobre Alldatasheet | Publicidade | Contato conosco | Privacy Policy | roca de Link | 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 |