ISL5100A Datasheet, PDF (8/13 Pages) Intersil Corporation – Quad 18V Pin Electronics Driver/Window Comparator

ISL55100A
Test Circuits and Waveforms (Continued)
VINP
CVA
-
+
COMP HI
QA
5V
+
CVB _-
QB
COMP LO
FIGURE 4. RECEIVER SWITCHING TEST CIRCUIT
VINP
0V
t_PDLH
QX
50%
500mV
0V
-500mV
t_PDHL
50%
V_OH (≈5V)
V_OL (≈0V)
FIGURE 5. RECEIVER PROPAGATION DELAY MEASUREMENT POINTS
Application Information
The ISL55100 provides Quad pin drivers and Quad dual
level comparator receivers in a small footprint. The four
channels may be used as bidirectional or split channels.
Drivers have per channel level, data, and high impedance
controls, while comparators have per channel high and low
threshold levels.
Receiver Features
The receivers are four independent window comparators that
feature high output current capability, and user defined high
and low output levels to interface with a wide variety of logic
families. Each receiver, comprises two comparators and each
comparator has an independent threshold level input, making
it easy to implement window comparator functions. The CVA
and CVB pins set the threshold levels of the A and B
comparators respectively. COMP HIGH and COMP LOW set
all the comparator output levels, and COMP HIGH must be
more positive than COMP LOW. These two inputs are
unbuffered supply pins, so the sources driving these pins
must provide adequate current for the expected load. COMP
HIGH and COMP LOW typically connect to the power
supplies of the logic device driven by the comparator outputs.
The truth table for the receivers is given on page 3. Receiver
outputs are not tri-statable, and do not incorporate any on-chip
8
short circuit current protection. Momentary short circuits to
GND, or any supply voltage, won’t cause permanent damage,
but care must be taken to avoid longer duration short circuits.
If tolerable to the application, current limiting resistors can be
inserted in series with the QA(0-3) and QB(0-3) Outputs to
protect the receiver outputs from damage due to overcurrent
conditions.
Driver Features
The drivers are single ended outputs featuring a wide
voltage range, an output stage capable of delivering 200mA
while providing a low out resistance and tri-state capability.
Additionally, the driver output can be toggled to drive one of
two user defined output levels High (VH) or Low (VL).
Driver waveforms are greatly affected by load
characteristics. The ISL55100 actually double bonds the
VH(0-3) and VL(0-3) supply pins for each channel. The
Driver Output Pins (DOUT(0-3)) are triple bonded. Multiple
bond wires help reduce the effects of Inductance between
the IC Die (Wafer) and the packaging. Also the QFN style of
packaging reduces inductance over other types of
packaging.
While the inductance of a bond wire might seem
insignificant, it can reduce high-frequency waveform fidelity.
So this should be borne in mind when doing PCB layout and
FN7486.0
October 31, 2005