E7804BHF Semtech, E7804BHF Datasheet - Page 8

• Manufacturer Part Number: E7804BHF
• Manufacturer: Semtech

Specifications of E7804BHF

• Operating Temperature (max): 100C
• Package Type: MQFP
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Not Compliant

comparator input is connected to approximately zero volts
when disconnected from VIO through ~50K . To prevent
the comparator outputs from switching due to noise when
not in use, the CVA/B inputs should be parked >250mV
from ground.
each channel, is combined with the register bit, and will
override the internal register bit and open the S2 switch
for the channel. In its low state, the OPN input will not
override and force the switch closed. (It should be noted
that OPN=1 will also open S1 to disconnect the channel’s
driver output from the VIO pin.) OPN is a fast way of
disconnecting the lower voltage driver and comparator
circuitry from the VIO pin. When the comparator (and
driver) are disconnected, the voltage at the VIO pin may
be in the range of the VEE to VXX power supplies.
Parametric Measurements
The Edge7804 incorporates a switch matrix which permits
an External Parametric Measurement Unit (EPMU) to be
connected to one or more channel’s POUT pin. The EPMU
range is a function of the VEE and VXX power supplies
with
directly to the VIO pin or connected by an inductor so as
to minimize the effect of the capacitance at the POUT pin
on the driver’s waveform and maximum frequency.
The EPMUF and EPMUS inputs are force and sense
inputs respectively and connect to the POUT output
pin through an internal, normally open, dual switch (S4).
There is one dual switch for each channel [0:3]. This
switch can be closed by serially programming the internal
register bit for the appropriate channel (see Table 2,
CH[0:3]_switches_&_states registers) denoted as S4 to
a logical “1”. Logical “0” will open the switch. The switch
and metal lines for the EMPUF path are sized to
accommodate the higher currents (up to 40mA). Do not
use EPMUS for higher currents. The EPMUS line is the
Kelvin sense path for the external PMU.
Continuity Test Circuit
Each channel has a programmable Continuity Test Circuit
(CTC) which can be switched to its POUT pin. The CTC
sinks current in the range –15 to –250 A as determined
by the voltage of the CTCFIV input pin which is common
to all CTC’s.
TEST AND MEASUREMENT PRODUCTS
Circuit Description (continued)
2005 Semtech Corp. / Rev. 5, 12/6/05
40 mA capability. Typically, POUT is connected
An external pin, OPN[0:3] one input for
8
The relationship between the CTCFIV input voltage and
the resulting current produced by the CTC uses the resistor
R
to current accuracy. The relationship is:
CTCLV input determines the voltage limit to which CTC may
sink current. CTCLV has a range of 0 to –2.0V and is
common to all channels’ CTCs. With POUT, connected
externally to VIO, then with CTC connected and sinking
current, the resultant voltage at VIO can be tested by the
channel’s comparators. As this voltage could be as low as
–2V, when performing a continuity test, a channel’s driver
should be disconnected in order to protect the driver, which
has a range of –0.2V to +5.2V. The driver output should
be disconnected by opening switch S1 when connecting
the CTC to the POUT pin. The CTC connects to the POUT
pin through the normally open switch S5. Switch S5 can
be closed by serially programming a logical “1” via the
internal register for the appropriate channel. See Table
2,”CH[0:3]_switches_&_states write instruction for the
individual channels.
Note that the CTC’s use the external resistor on the
EREF pin to calculate the I
driver output impedance calibration also uses this
reference. If any CTC is switched in-circuit (S5
closed), then attempting to calibrate the driver output
impedance will fail and not occur. No change to the
calibration values will take place.
A typical continuity test will program the CTC’s force current
to –100 A, its voltage limit at –2V, and CVA and CVB at –
0.5V and –1.5V, respectively, so as to detect shorts, opens
and continuity. Typically, in this test, the DUT power supplies
are all set to zero volts. The continuity test will determine
if each pin of the DUT is connected to the pin channel in
the tester without shorts to supplies or ground.
EREF
, as a reference. This gives a good degree of voltage
CVB = –1.5V
CTCLV = –2V
CVA = –0.5V
I
CTC
= –1.09 * [CTCFIV(V) / R
0V
CTC
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}
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test currents. The
Edge7804
PRELIMINARY
EREF
Continuity
Open
Short
www.semtech.com
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