XR17V354IB-E4-EVB Datasheet, PDF (8/67 Pages) Exar Corporation – HIGH PERFORMANCE QUAD PCI-EXPRESS UART

XR17V354
HIGH PERFORMANCE QUAD PCI-EXPRESS UART
PIN DESCRIPTIONS
REV. 1.0.4
NAME
PIN #
TYPE
DESCRIPTION
BUCK REGULATOR SIGNALS
ENABLE
C14
I Logic ’1’ enables, logic ’0’ disables buck regulator output.
LX
A13
O Output of internal buck regulator. Use 4.7 uH inductor and connect to FB pin
LX
A14
O ^{as shown in Figure 3.}
FB
C11
I Buck regulator feedback. Decouple with 47uF capacitor and connect to LX
pins through 4.7 uH inductor as shown in Figure 3.
PWRGD
D13
O Indicates that 1.2V core has been powered up.
ANCILLARY SIGNALS
RESET#
R2
I System reset (active low). In normal operation, this signal should be HIGH.
TMRCK
A10
I 16-bit timer/counter external clock input.
EN485#
C10
I Auto RS-485 mode enable (active low). This pin is sampled during power up,
following a hardware reset (RST#) or soft reset (register RESET). It can be used
to start up all 4 UARTs in the Auto RS-485 Half-Duplex Direction control mode.
The sampled logic state is transferred to FCTR bit-5 in the UART channel.
ENIR#
B10
I Infrared mode enable (active low). This pin is sampled during power up, fol-
lowing a hardware reset (RST#) or soft-reset (register RESET). It can be
used to start up all 4 UARTs in the infrared mode. The sampled logic state is
transferred to MCR bit-6 in the UART.
TEST0
TEST1
TEST2
F2
I Factory Test Modes. For normal operation, connect to GND.
B11
I
A11
I
POWER / GROUND / NO CONNECT
VCC33
D5, D9, E12,
J12, M7
Pwr 3.3V I/O power supply.
VCC33A
K3
Pwr 3.3V analog PHY power supply. A ferrite bead is recommended on this pin.
VCC33P
B13, C13
Pwr 3.3V power supply voltage for output stage of buck regulator.
VCC33B
B14, B15
Pwr 3.3V power supply for the analog blocks of the buck regulator.
VCC12
D7, D11, E4,
G12, K4, L12,
M9
Pwr 1.2V core power supply. A ferrite bead is recommended on these pins.
VCC12A
K2
Pwr 1.2V analog PHY power supply. A ferrite bead is recommended on this pin.
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