ISL54208EVAL1Z Intersil, ISL54208EVAL1Z Datasheet - Page 9

• Manufacturer Part Number: ISL54208EVAL1Z
• Description: EVALUATION BOARD FOR ISL54208
• Manufacturer: Intersil

Specifications of ISL54208EVAL1Z

• Main Purpose: Interface, Analog & Digital Switch
• Embedded: No
• Utilized Ic / Part: ISL54208
• Primary Attributes: 2 x SPDT Audio, USB & Video Switch
• Secondary Attributes: 1.8 V ~ 5.5 V Supply
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

audio/video playback are intended to be mutually exclusive
operations.
NC1 and NC2 Audio/Video Switches
The two NC (normally closed) audio/video switches (NC1,
NC2) are 3Ω switches that can pass signals that swing
below ground by as much as 1.5V. They were designed to
pass ground reference audio signals and dc restored
composite base-band signals (CVBS) including negative
synchronizing pulse with minimal insertion loss and very low
distortion and degradation.
The -3dB bandwidth into 75Ω is 338MHz (Figure 17).
Crosstalk between NC1 and NC2 @ 4MHz is -78dB
(Figure 16) which allows composite video to be routed
through one switch and mono-audio through the other switch
with little interference.
The recommended maximum signal range is from -1.5V to
1.5V. You can apply positive signals greater than 1.5V but
the r
1.5V. The signal should not be allowed to exceed the V
rail or swing more negative than -1.5V.
Over a signal range of ±1V (0.707Vrms) with V
these switches have an extremely low r
variation. They can pass a ground referenced audio signal
with very low distortion (<0.06% THD+N) when delivering
15.6mW into a 32Ω headphone speaker load. See Figures
10, 11, 12, and 13 THD+N performance curves.
Figures 8 and 9 shows the vector scope plots of a standard
NTSC color bar signal at both the input (Figure 8) and output
(Figure 9) of the ISL54208. The plots show that except for a
little attentuation, due to switch R
there is virtually no degradation of the video waveform
through the switch.
ON
FIGURE 8. VECTOR-SCOPE PLOT BEFORE SWITCH
resistance of the switch increases rapidly above
9
ON
and test fixture cabling,
ON
resistance
DD
>2.7V,
DD
ISL54208
Figure 18 shows the differential gain (DG) and differential
phase (DP) plots at the output of the switch using an actual
NTSC composite video signal and a VM700A Video
Measurement Test Set. DG = 0.28% and DP = 0.04deg.
The 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).
The NC switches are active (turned ON) whenever the IN
voltage is
Note: Whenever the NC switches are ON the USB
transceiver drivers need to be in the high impedance state or
static high or low state.
NO1 and NO2 USB Switches
The two NO (normally open) USB switches (NO1, NO2) are
5Ω bidirectional switches that were designed to pass high-
speed USB differential signals in the range of ±0V to 400mV.
These switches have low capacitance and high bandwidth to
pass USB high-speed signals (480Mbps) with minimum
edge and phase distortion to meet high-speed USB 2.0 high-
speed signal quality specifications. See Figure 14 for High-
speed Eye Pattern taken with switch in the signal path.
The maximum signal range for the USB switches is from
-1.5V to V
not be allow to exceed the V
ground by more than -1.5V.
The NO switches are active (turned ON) whenever the IN
voltage is to
Note: Whenever the NO 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.
FIGURE 9. VECTOR-SCOPE PLOT AFTER SWITCH
≤
DD
to 0.5V and the CTRL voltage to
≥
. The signal voltage at NO1 and NO2 should
1.4V.
DD
voltage rail or go below
≥
1.4V.
December 18, 2006
FN6410.0