ISL41387IRZ Intersil, ISL41387IRZ Datasheet - Page 18

• Manufacturer Part Number: ISL41387IRZ
• Description: IC TXRX DUAL PROTOCAL ESD 40-QFN
• Manufacturer: Intersil
• Type: Transceiverr

Specifications of ISL41387IRZ

• Number Of Drivers/receivers: 2/2
• Protocol: RS422, RS485
• Voltage - Supply: 4.5 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 40-VFQFN, 40-VFQFPN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

minimize EMI and reflections. Nevertheless, for the best jitter
performance when driving long cables, the faster speed
options may be preferable, even at lower data rates. The
faster output transitions deliver less variability (jitter) when
loaded with the large capacitance associated with long
cables. Figures 42, 43, and 44 detail the jitter performance of
the three speed options while driving three different cable
lengths. The figures show that under all conditions the faster
the edge rate, the better the jitter performance. Of course,
faster transitions require more attention to ensuring short
stub lengths, and quality terminations, so there are trade-offs
to be made. Assuming a jitter budget of 10%, it is likely
better to go with the slow speed option for data rates of
115kbps or less, to minimize fast edge effects. Likewise, the
medium speed option is a good choice for data rates
between 115kbps and 460kbps. For higher data rates, or
when the absolute best jitter is required, use the high speed
option.
Evaluation Board
An evaluation board, part number ISL41387EVAL1, is
available to assist in assessing the dual protocol IC’s
performance. The evaluation board contains a QFN
packaged device, but because the same die is used in all
packages, the board is also useful for evaluating the
functionality of the other versions. The board’s design allows
for evaluation of all standard features, plus the QFN specific
features. Refer to the evaluation board application note for
details and contact your sales rep for ordering information.
Typical Performance Curves
FIGURE 13. RECEIVER OUTPUT CURRENT vs RECEIVER
50
40
30
20
10
0
0
OUTPUT VOLTAGE
1
RECEIVER OUTPUT VOLTAGE (V)
V
OH
2
18
, +85°C
V
OH
3
, +25°C
V
V
OL
V
CC
OL
, +25°C
4
, +85°C
= V
L
ISL81387, ISL41387
= 5V, T
5
A
= +25°C; Unless Otherwise Specified.
Tx/Rx
FIGURE 14. RECEIVER HIGH OUTPUT VOLTAGE vs LOGIC
FIGURE 12. USING ACTIVE LOW vs ACTIVE HIGH RX
ACTIVE LOW RX ENABLE
ACTIVE HIGH RX ENABLE
5
4
3
2
1
0
0
Tx/Rx
OR NC
1kΩ
SUPPLY VOLTAGE (V
ENABLE
RA
RXEN
RXEN *
* QFN ONLY
1
DEN
RXEN *
RXEN
DY
DEN
RA
DY
ISL41387
I
OH
ISL41387
D
= -1mA
2
R
D
V
R
L
GND
+5V
V
(V)
CC
B
A
Y
Z
L
GND
V
+5V
B
A
Y
Z
)
CC
3
I
OH
I
OH
= -4mA
= -8mA
+
4
0.1µF
November 21, 2007
+
0.1µF
FN6201.3
5