ISL54416 Datasheet, PDF (10/14 Pages) Intersil Corporation – Low Voltage, Dual SPDT, USB/CVBS/ Audio Switches with Negative Signal Capability

ISL54415, ISL54416, ISL54417
FIGURE 8. VECTOR-SCOPE PLOT BEFORE SWITCH
FIGURE 9. VECTOR-SCOPE PLOT AFTER SWITCH
Figure 15 shows the measured gain and phase of a
3.58MHz, 300MV_P-P signal at the output of the switch
relative to the signal at the input of the switch as you vary the
DC offset of the signal from 0V to 1V using a network
analyzer. The data from the sweep was used to calculated
the differential gain (DG) and differential phase (DP). Over
luminance range of 0V to 1V: DG = 0.03% and DP = 0.05°.
Over luminanace range of 0V to 0.7V: DG = 0.03% and
DP = 0.03°. DG and DP plot using an actual NTSC video
signal is shown in Figure 16. DG = 0.05% and DP = 0.02°.
These NC switches are uni-directional switches. The
audio/video sources should be connected at the NC side of
the switch (pins 7 and 8) and the speaker load and video
receiver should be connected at the COM side of the switch
(pins 3 and 4).
For the ISL54415 and ISL54416 parts the NC audio/video
switches are active (turned ON) whenever the V_BUS voltage
is ≤ V_DD + 0.2V. The V_BUS pin is internally pulled low
through a pull-down resistor allowing the V_BUS pin to float.
When the V_BUS pin is floating the NC audio/video switches
are ON.
Note: Whenever the audio/video switches are ON the USB
transceivers need to be in the high impedance state or static
high or low state to keep from interfering with the audio/video
transmission.
For the ISL54417 part the NC1 audio/video switch is active
(turned ON) whenever logic pin IN1 (pin 10) is LOW. The
NC2 audio/video switch is active (turned ON) whenever the
logic pin IN2 (pin 2) is LOW. Unlike the ISL54415 and
ISL54416 parts were the two SPDT switches work in
tandem, the ISL54417 gives you independent control over
each SPDT switch.
NO1 and NO2 USB Switches
The two NO (normally open) USB switches (NO1, NO2) are
5Ω bidirectional switches that were designed to pass low
speed and full-speed USB differential signals typically in the
range of 0V to 3.6V. The switches have low capacitance
(0.47pF) and high bandwidth (239MHz) to pass USB full-
speed signals (12Mbps) with minimum edge and phase
distortion to meet USB 2.0 signal quality specifications. See
Figure 12 for full-speed USB eye diagram.
For the ISL54415 and ISL54416 parts the maximum signal
range for the USB switches is from -1.5V to V_BUS. The
signal voltage should not be allow to exceed the V_BUS
voltage rail or go below ground by more than -1.5V.
For the ISL54417 part the maximum signal range is from
-1.5V to V_DD. The signal voltage should not be allowed to
exceed the V_DD voltage rail or go below ground by more
than -1.5V.
When using the ISL54415 and ISL54416 parts the USB
switches are active (turned ON) whenever the V_BUS voltage
is ≥V_DD + 0.8V. V_BUS is internally pulled low, so when V_BUS
is floating the USB switches are OFF.
Note: Whenever the USB switches are ON the audio and
video drivers need to be at AC or DC ground or floating to
keep from interfering with the data transmission.
When using the ISL54417 part the NO1 USB switch is active
(turned ON) whenever logic pin IN1 (pin 10) is HIGH. The
NO2 USB switch is active (turned ON) whenever the logic
pin IN2 (pin 2) is HIGH. Unlike the ISL54415 and ISL54416
parts were the two SPDT switches work in tandem, the
ISL54417 gives you independent control over each SPDT
switch.
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FN6318.1
June 27, 2006