Datasheet
Dual Serial UART with 128-Word FIFOs
MAX3109
7Maxim Integrated
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
(Voltages referenced to AGND.)
V
L
, V
CC
, V
EXT
, XIN ............................................... -0.3V to +4.0V
XOUT
........................................................ -0.3V to (V
CC
+ 0.3V)
V
18
......................
-0.3V to the lesser of (V
CC
+ 0.3V) and 2.0V
RST, IRQ, MOSI/A1, CS/A0, SCLK/SCL,
MISO/SDA, LDOEN, SPI/I2C
.................... -0.3V to (V
L
+ 0.3V)
TX_, RX_, CTS_, GPIO_
........................... -0.3V to (V
EXT
+ 0.3V)
DGND
...................................................................-0.3V to +0.3V
Continuous Power Dissipation (T
A
= +70NC)
TQFN (derate 34.5mW/NC above +70NC)
.............. 2758.6mW
Operating Temperature Range
.......................... -40NC to +85NC
Maximum Junction Temperature
.....................................+150NC
Storage Temperature Range
............................ -65NC to +150NC
Lead Temperature (soldering, 10s)
................................+300NC
Soldering Temperature (reflow)
......................................+260NC
TQFN
Junction-to-Ambient Thermal Resistance (B
JA
) ........... 47NC/W
Junction-to-Case Thermal Resistance (B
JC
) ...............1.7NC/W
DC ELECTRICAL CHARACTERISTICS
(V
CC
= 1.71V to 3.6V, V
L
= 1.71V to 3.6V, V
EXT
= 1.71V to 3.6V, T
A
= -40NC to +85NC, unless otherwise noted. Typical values are at
V
CC
= 2.8V, V
L
= 1.8V, V
EXT
= 2.5V, T
A
= +25NC.) (Notes 2, 3)
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-lay-
er board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
ABSOLUTE MAXIMUM RATINGS
PACKAGE THERMAL CHARACTERISTICS (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Digital Interface Supply Voltage V
L
1.71 3.6 V
Analog Supply Voltage V
CC
Internal PLL disabled and bypassed 1.71 3.6
V
Internal PLL enabled 2.35 3.6
UART Interface Logic Supply
Voltage
V
EXT
1.71 3.6 V
Logic Supply Voltage V
18
1.65 1.95 V
CURRENT CONSUMPTION
V
CC
Supply Current I
CC
1.8MHz crystal oscillator active, PLL
disabled, SPI/I
2
C interface idle, UART
interfaces idle, LDOEN = high
500
FA
Baud rate = 1Mbps, 20MHz external clock,
SPI/I
2
C interface idle, PLL disabled, all
UARTs in loopback mode, LDOEN = low
500
V
18
Input Power-Supply Current
in Shutdown Mode
I
18SHDN
RST = low, all inputs and outputs are idle
100
FA
V
CC
+ V
L
+ V
A
Shutdown Supply
Current
I
SHDN
RST = low, MISO, SCLK, MOSI, SPI_I2C,
CS, LDOEN = 0/V
L
, CTSB0/1 = 0/V
EXT
,
CTSB0/1 = 0/V
EXT
0 1
FA