MAX14841EATA+T Maxim Integrated Products, MAX14841EATA+T Datasheet - Page 13

• Manufacturer Part Number: MAX14841EATA+T
• Description: IC TXRX RS485 40MBPS 8TDFN
• Manufacturer: Maxim Integrated Products
• Type: Transceiverr

Specifications of MAX14841EATA+T

• Number Of Drivers/receivers: 1/1
• Protocol: RS485
• Voltage - Supply: 3 V ~ 3.6 V
• Mounting Type: Surface Mount
• Package / Case: 8-TDFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MAX14841EATA+T

The MAX14840E/MAX14841E DE and RE enable inputs
feature hot-swap capability. At the input, there are two
nMOS devices, M1 and M2 (Figure 10). When V
ramps from 0V, an internal 15Fs timer turns on M2 and
sets the SR latch that also turns on M1. Transistors M2
(a 1mA cur rent sink) and M1 (a 100FA current sink) pull
DE to GND through a 5.6kI resistor. M2 is designed to
pull DE to the disabled state against an external parasitic
capaci tance up to 100pF that can drive DE high. After
15µs, the timer deactivates M2 while M1 remains on,
holding DE low against three-state leakages that can
drive DE high. M1 remains on until an external source
overcomes the required input current. At this time, the
SR latch resets and M1 turns off. When M1 turns off,
DE reverts to a standard, high-impedance CMOS input.
Whenever V
reset.
For RE, there is a complementary circuit employing two
pMOS devices pulling RE to V
Figure 10. Simplified Structure of the Driver Enable Pin (DE)
CC
drops below 1V, the hot-swap input is
______________________________________________________________________________________
DE
How-Swap Input Circuitry
5.6kI
TIMER
TIMER
CC
40Mbps, +3.3V, RS-485 Half-Duplex
V
CC
.
M1
100FA
15Fs
1mA
M2
CC
ESD protection structures are incorporated on all pins
to protect against electrostatic discharges encountered
during handling and assembly. The driver outputs and
receiver inputs of the MAX14840E family of devices have
extra protection against static electricity. The ESD struc-
tures withstand high ESD in all states: normal operation,
shutdown, and powered down. After an ESD event, the
MAX14840E/MAX14841E keep working without latchup
or damage.
ESD protection can be tested in various ways. The trans-
mitter outputs and receiver inputs of the MAX14840E/
MAX14841E are characterized for protection to the fol-
lowing limits:
• Q35kV HBM
• Q20kV using the Air Gap Discharge method specified
• Q12kV using the Contact Discharge method specified
in IEC 61000-4-2
in IEC 61000-4-2
Transceivers
±35kV ESD Protection
DRIVER
ENABLE
(HOT SWAP)
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