General Description
The MAX3349E ±15kV ESD-protected, USB transceiver
provides a full-speed USB interface to a lower voltage
microprocessor or ASIC. The device supports enumer-
ation, suspend, and VBUS detection. A special UART
multiplexing mode routes external UART signals (Rx
and Tx) to D+ and D-, allowing the use of a shared con-
nector to reduce cost and part count for mobile
devices.
The UART interface allows mobile devices such as
PDAs, cellular phones, and digital cameras to use either
UART or USB signaling through the same connector.
The MAX3349E features a separate UART voltage sup-
ply input to support legacy devices using +2.75V signal-
ing. The MAX3349E supports a maximum UART baud
rate of 921kbaud.
Upon connection to a USB host, the MAX3349E enters
USB mode and provides a full-speed USB 2.0-compliant
interface through VP, VM, RCV, and OE. The MAX3349E
features internal series termination resistors on D+ and
D-, and an internal 1.5kΩpullup resistor to D+ to allow
the device to logically connect and disconnect from the
USB while plugged in. A suspend mode is provided for
low-power operation. D+ and D- are protected from
electrostatic discharge (ESD) up to ±15kV.
The MAX3349E is available in 16-pin TQFN (4mm x
4mm) and 16-bump UCSP™ (2mm x 2mm) packages,
and is specified over the -40°C to +85°C extended tem-
perature range.
Applications
Features
♦±15kV ESD HBM Protection on D+ and D-
♦UART Mode Routes External UART Signals to
D+/D-
♦Internal Linear Regulator Allows Direct Powering
from the USB Cable
♦Separate Voltage Input for UART
Transmitter/Receiver (VUART)
♦Internal 1.5kΩPullup Resistor on D+ Controlled
by Enumerate Input
♦Internal Series Termination Resistors on D+ and D-
♦Complies with USB Specification Revision 2.0,
Full-Speed 12Mbps Operation
♦Built-In Level Shifting Down to +1.4V, Ensuring
Compatibility with Low-Voltage ASICs
♦VBUS Detection
♦Combined VP and VM Inputs/Outputs
♦No Power-Supply Sequencing Required
♦Available in 16-Bump UCSP (2mm x 2mm)
Package
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
________________________________________________________________
Maxim Integrated Products
1
19-3952; Rev 1; 5/11
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Ordering Information
TQFN-EP
(4mm x 4mm)
ENUM
16
1234
12 11 10 9
15
14
13
5
6
7
8
VM
VL
VTRM
VBUS
D+
D-
GND
RX
TX
BD
VP
RCV
OE
SUS
VUART
MAX3349E
TOP VIEW
*EP
+
UCSP
(2mm x 2mm)
MAX3349E
TOP VIEW
(BUMPS ON BOTTOM OF DIE)
A
B
C
123
RX TX
VUART
VP
VL
ENUM SUS
VTRM
BD
VM RCV
OE
4
DD+ D-
VBUS GND
*CONNECT TO GND OR LEAVE UNCONNECTED.
+
PART TEMP RANGE PIN-PACKAGE
MAX3349EEBE-T -40°C to +85°C 16 UCSP
MAX3349EEBE+T -40°C to +85°C 16 UCSP
MAX3349EETE* -40°C to +85°C 16 TQFN-EP**
Pin Configurations
UCSP is a trademark of Maxim Integrated Products, Inc.
*
Future product—contact factory for availability.
T = Tape and reel.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
**
EP = Exposed pad.
Cell Phones
PDAs
Digital Cameras
MP3 Players
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
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.
(All voltages referenced to GND, unless otherwise noted.)
VUART, VL, VBUS, D+, D- ..........................................-0.3V to +6V
VTRM .........................................................-0.3V to (VBUS + 0.3V)
VP, VM, SUS, RX, TX, ENUM, RCV, OE, BD, -0.3V to (VL+ 0.3V)
Short Circuit Current (D+ and D-)...................................±150mA
Maximum Continuous Current (all other pins) .................±15mA
Continuous Power Dissipation (TA= +70°C)
UCSP (derate 8.2mW/°C above +70°C) ....................659.5mW
TQFN (derate 25.0mW/°C above +70°C) ...................2000mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature .....................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Bump Temperature (soldering, reflow) ............................+235°C
Soldering Temperature (reflow) .......................................+260°C
ELECTRICAL CHARACTERISTICS
(VBUS = +3.0V to +5.5V, VUART = +2.7V to +3.3V, VL= +1.40V to +2.75V, TA= -40°C to +85°C, unless otherwise noted. Typical val-
ues are at VBUS = +5V, VL= +1.8V, VUART = +2.75V (UART Mode), and TA= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
SUPPLY INPUTS/OUTPUTS (VBUS, VUART, VTRM, VL)
VBUS Input Range VBUS USB mode 3.0 5.5 V
4.5V VBUS 5.5V
VL Input Range VL3.0V VBUS 4.5V 1.40 2.75 V
VUART Input Range VUART UART mode 2.7 3.3 V
VBUS > 4.5V 3.0 3.6
Regulated Supply-Voltage Output VTRM Internal regulator,
USB mode VBUS < 4.5V 2.8 3.6 V
Operating VBUS Supply Current IBUS Full-speed transmitting/receiving at
12Mbps, CL= 50pF on D+ and D- 10 mA
Operating VUART Supply Current IVUART UART transmitting/receiving at
921kbaud, CL = 200pF 2.5 mA
Static VUART Supply Current IVUART(STATIC) UART mode 3.5 5 µA
Operating VL Supply Current IVL Full-speed transmitting/receiving at
12Mbps, CL= 50pF on D+ and D- 6 mA
Full-speed idle,
VD+ > +2.7V, VD- < +0.3V 290 400
Full-Speed Idle and SE0 Supply
Current IVBUS(IDLE)
SE0: VD+ < +0.3V, VD- < +0.3V 340 450
µA
Static VL Supply Current IVL(STATIC) Full-speed idle, SE0, suspend mode,
or static UART mode 2 10 µA
Sharing Mode VL Supply Current IVL(OFF) V
BUS and VUART not present 2 5 µA
USB Suspend VBUS Supply
Current IVBUS(SUS) VM, VP unconnected;
OE = 1, SUS = 1 38 65 µA
VBUS DETECTION (BD)
USB Power-Supply Detection
Threshold VTH_VBUS 0.4 x
VL
0.9 x
VLV
USB Power-Supply Detection
Hysteresis VHYS_VBUS 40 mV
VL Power-Supply Detection
Threshold VTH_VL 0.7 V
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VBUS = +3.0V to +5.5V, VUART = +2.7V to +3.3V, VL= +1.40V to +2.75V, TA= -40°C to +85°C, unless otherwise noted. Typical val-
ues are at VBUS = +5V, VL= +1.8V, VUART = +2.75V (UART Mode), and TA= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
VUART Power-Supply Detection
Threshold VTH_UART 0.4 x
VL
0.65 x
VL
0.9 x
VLV
DIGITAL INPUTS/OUTPUTS (VP, VM, RCV, SUS, OE, RX, TX, ENUM, BD)
Input-Voltage Low VIL
0.3 x
VLV
Input-Voltage High VIH 0.7 x
VL V
Output-Voltage Low VOL IOL = +2mA, VL > 1.65V
IOL = +1mA, VL < 1.65V 0.4 V
Output-Voltage High VOH IOH = +2mA, VL > 1.65V
IOH = +1mA, VL < 1.65V
VL -
0.4 V
Input Leakage Current ILKG -1 +1 µA
ANALOG INPUTS/OUTPUTS (D+, D- in USB Mode)
Differential Input Sensitivity VID |VD+ - VD-| 0.2 V
Differential Common-Mode
Voltage VCM Includes VID range 0.8 2.5 V
Single-Ended Input
Low Voltage VILSE 0.8 V
Single-Ended Input
High Voltage VIHSE 2.0 V
USB Output-Voltage Low VUSB_OLD R
L = 1.5k connected to +3.6V 0.3 V
USB Output-Voltage High VUSB_OHD R
L = 15k connected to GND 2.8 3.6 V
Off-State Leakage Current ILZ -1 +1 µA
Driver Output Impedance ZDRV Steady-state drive 28 43
Transceiver Capacitance CIND Measured from D+/D- to GND 20 pF
Input Impedance ZIN Driver off 1 M
D+ Internal Pullup Resistor RPU ENUM = 1 1425 1500 1575
ANALOG INPUTS/OUTPUTS (D+, D- in UART Mode)
Input-Voltage High VUART_IH UART mode, +2.70 < VUART < +2.85V 2.0 V
Input-Voltage Low VUART_IL UART mode,
+2.70V < VUART < +2.85V 0.8 V
Output-Voltage High VUART_OH
UART mode,
+2.70V < VUART < +2.85V
IUART_OH = -2mA
2.2 V
Output-Voltage Low VUART_OL
UART mode,
+2.70V < VUART < +2.85V
IUART_OL = +2mA
0.4 V
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(VBUS = +3.0V to +5.5V, VUART = +2.7V to +3.3V, VL= +1.40V to +2.75V, TA= -40°C to +85°C, unless otherwise noted. Typical val-
ues are at VBUS = +5V, VL= +1.8V, VUART = +2.75V (UART Mode), and TA= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
ESD PROTECTION (D+, D-)
Human Body Model (Figures 9 and 10) ±15 kV
IEC 61000-4-2
Air-Gap Discharge ±8 kV
IEC 61000-4-2
Contact Discharge ±8 kV
TIMING CHARACTERISTICS
(VBUS = +3.0V to +5.5V, VUART = +2.7V to +3.3V, VL= +1.4V to +2.75V, TA= -40°C to +85°C, unless otherwise noted. Typical values
are at VBUS = +5V, VL= +1.8V, VUART = +2.75V (UART Mode), and TA= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
USB DRIVER CHARACTERISTICS (CL = 50pF)
Rise Time tFR 10% to 90% of | VUSB_OHD - VUSB_OLD |
(Figures 1 and 7) 420ns
Fall Time tFF 90% to 10% of | VUSB_OHD - VUSB_OLD |
(Figures 1 and 7) 420ns
Rise/Fall Time Matching tFR/tFF Excluding the first transition from idle
state (Note 2) (Figures 1 and 7) 90 110 %
Output Signal Crossover Voltage VCRS_F Excluding the first transition from idle
state (Note 2) (Figure 2) 1.3 2.0 V
VL > +1.65V (Figures 2 and 7) 22.5
tPLH_DRV +1.4V < VL < +1.65V (Figures 2 and 7) 25
VL > +1.65V (Figures 2 and 7) 22.5
Driver Propagation Delay
tPHL_DRV +1.4V < VL < +1.65V (Figures 2 and 7) 25
ns
tPHZ_DRV High-to-off transition (Figures 3 and 6) 25
Driver Disable Delay tPLZ_DRV Low-to-off transition (Figures 3 and 6) 25 ns
tPZH_DRV Off-to-high transition (Figures 3 and 7) 25
Driver Enable Delay tPZL_DRV Off-to-low transition (Figures 3 and 7) 25 ns
USB RECEIVER CHARACTERISTICS (CL = 15pF)
VL > +1.65V (Figures 4 and 8) 25
tPLH_RCV +1.4V < VL < +1.65V (Figures 4 and 8) 30
VL > +1.65V (Figures 4 and 8) 25
Differential Receiver Propagation
Delay
tPHL_RCV 1.4V < VL < +1.65V (Figures 4 and 8) 30
ns
VL > +1.65V (Figures 4 and 8) 28
tPLH_SE +1.4V < VL < +1.65V (Figures 4 and 8) 35
VL > +1.65V (Figures 4 and 8) 28
Single-Ended Receiver
Propagation Delay tPHL_SE +1.4V < VL < +1.65V (Figures 4 and 8) 35
ns
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
_______________________________________________________________________________________ 5
TIMING CHARACTERISTICS (continued)
(VBUS = +3.0V to +5.5V, VUART = +2.7V to +3.3V, VL= +1.4V to +2.75V, TA= -40°C to +85°C, unless otherwise noted. Typical values
are at VBUS = +5V, VL= +1.8V, VUART = +2.75V (UART Mode), and TA= +25°C.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
High-to-off transition,
VL > +1.65V (Figure 5) 10
tPHZ_SE High-to-off transition,
+1.4V < VL < +1.65V (Figure 5) 12
Low-to-off transition,
VL > +1.65V (Figure 5) 10
Single-Ended Receiver Disable
Delay
tPLZ_SE Low-to-off transition,
+1.4V < VL < +1.65V (Figure 5) 12
ns
Off-to-high transition,
VL > +1.65V (Figure 5) 20
tPZH_SE Off-to-high transition,
+1.4V < VL < +1.65 (Figure 5) 20
Off-to-low transition,
VL > +1.65V (Figure 5) 20
Single-Ended Receiver Enable
Delay
tPZL_SE Off-to-low transition,
+1.4V < VL < +1.65V (Figure 5) 20
ns
UART DRIVER CHARACTERISTICS (CL = 200pF)
Rise Time (D-) tFR_TUART 10% to 90% of |VOHD - VOLD| (Figure 13) 60 200 ns
Fall Time (D-) tFF_TUART 90% to 10% of |VOHD - VOLD| (Figure 13) 60 200 ns
tPLH_TUART (Figure 13) 70 200
Driver Propagation Delay tPHL_TUART (Figure 13) 70 200 ns
UART RECEIVER CHARACTERISTICS (CL = 15pF)
tPLH_RUART (Figure 14) 60
Receiver (Rx) Propagation Delay tPHL_RUART (Figure 14) 60 ns
tFR_RUART (Figure 14) 45
Receiver (Rx) Rise/Fall Time tFF_RUART (Figure 14) 45 ns
Note 1: Parameters are 100% production tested at TA=+25°C, unless otherwise noted. Limits over temperature are guaranteed
by design.
Note 2: Guaranteed by design; not production tested.
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
6 _______________________________________________________________________________________
Typical Operating Characteristics
(VBUS = +5V, VL= +3.3V, VUART = +2.75V, TA= +25°C, unless otherwise noted.)
0
10
30
20
40
50
1.4 1.81.6 2.0 2.2 2.4 2.6
SINGLE-ENDED RECEIVER
PROPAGATION DELAY vs. VL
MAX3349E toc01
VL (V)
PROPAGATION DELAY (ns)
TA = +85°C
TA = +25°C
TA = -40°C
12
14
18
16
20
22
4.00 4.504.25 4.75 5.00 5.25 5.50
SINGLE-ENDED RECEIVER
PROPAGATION DELAY vs. VBUS
MAX3349E toc02
VBUS (V)
PROPAGATION DELAY (ns)
TA = +85°C
TA = +25°C
TA = -40°C
0
1
3
2
4
5
1.4 1.81.6 2.0 2.2 2.4 2.6
LOGIC CURRENT CONSUMPTION
IN SUSPEND MODE
MAX3349E toc03
VL (V)
IVL (µA)
30
33
32
31
34
35
36
37
38
39
40
4.00 4.504.25 4.75 5.00 5.25 5.50
VBUS CURRENT CONSUMPTION
IN SUSPEND MODE
MAX3349E toc04
VBUS (V)
IVCC (µA)
0.45
0.47
0.51
0.49
0.53
0.55
08040 120 160 200 240
VL CURRENT DURING USB OPERATION
vs. D+/D- CAPACITANCE
MAX3349E toc05
D+/D- CAPACITANCE (CL)
IVL (mA)
12Mbps DATA RATE
TRANSMITTING
0
4
12
8
16
20
08040 120 160 200 240
VBUS CURRENT DURING USB OPERATION
vs. D+/D- CAPACITANCE
MAX3349E toc06
D+/D- CAPACITANCE (CL)
IVBUS (mA)
12Mbps DATA RATE
TRANSMITTING
10ns/div
SUSPEND MODE
RCV
2V/div
SUS
2V/div
MAX3349E toc07
4µs/div
BUS DETECT RESPONSE
BD
1V/div
VBUS
2V/div
MAX3349E toc08
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
_______________________________________________________________________________________ 7
Pin Description
PIN
UCSP TQFN TYPE NAME FUNCTION
A1 1 POWER VUART
UART Supply Voltage. VUART powers the internal UART transmitter and receiver.
Connect a regulated voltage between +2.7V and +3.3V to VUART. Bypass VUART to
GND with a 0.1µF ceramic capacitor.
A2 2 OUTPUT RX
UART Receive Output. In UART mode, RX is a level-shifted output that expresses
the logic state of D+.
A3 3 INPUT TX UART Transmit Input. In UART mode, D- follows the logic state on TX.
A4 4 OUTPUT BD
USB Detect Output. When VBUS exceeds the VTH-BUS threshold, BD is logic-high
to indicate that the MAX3349E is connected to a USB host. The MAX3349E
operates in USB mode when BD is logic-high, and operates in UART mode when
BD is logic-low.
B1 15 POWER VLDigital Logic Supply. Connect a +1.4V to +2.75V supply to VL. Bypass VL to GND
with a 0.1µF or larger ceramic capacitor.
B2 16 I/O VM
Receiver Output/Driver Input. VM functions as a receiver output when OE = VL. VM
follows the logic state of D- when receiving. VM functions as a driver input when
OE = GND (Tables 2 and 3).
B3 5 I/O VP
Receiver Output/Driver Input. VP functions as a receiver output when OE = VL. VP
follows the logic state of D+ when receiving. VP functions as a driver input when
OE = GND (Tables 2 and 3).
B4 6 OUTPUT RCV
Differential Receiver Output. In USB mode, RCV is the output of the USB
differential receiver (Table 3).
C1 14 POWER VTRM
Internal Regulator Output. VTRM provides a regulated +3.3V output. Bypass VTRM
to GND with a 1µF ceramic capacitor. VTRM draws power from VBUS. Do not power
external circuitry from VTRM.
C2 13 INPUT ENUM
Enumerate Input. Drive ENUM to VL to connect the internal 1.5k resistor from D+
to VTRM (when VBUS is present). Drive ENUM to GND to disconnect the internal
1.5k pullup resistor. ENUM has no effect when the device is in UART mode.
C3 8 INPUT SUS
Suspend Input. Drive SUS low for normal operation. Drive SUS high to force the
MAX3349E into suspend mode.
C4 7 INPUT OE
Output Enable. Drive OE low to set VP/VM to transmitter inputs in USB mode. Drive
OE high to set VP/VM to receiver outputs in USB mode. OE has no effect when the
device is in UART mode.
D1 12 POWER VBUS USB Supply Voltage. VBUS provides power to the internal linear regulator when in
USB mode. Bypass VBUS to GND with a 0.1µF ceramic capacitor.
D2 11 I/O D+ USB Differential Data Input/Output. Connect D+ directly to the USB connector.
D3 10 I/O D- USB Differential Data Input/Output. Connect D- directly to the USB connector.
D4 9 POWER GND Ground
— EP — EP Exposed Pad. Connect exposed paddle to GND.
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
8 _______________________________________________________________________________________
90%
10%
90%
10%
tFR, tFR_TUART tFF, tFF_TUART
VUSB_OLD, VOLD
VUSB_OHD, VOHD
Figure 1. Rise and Fall Times
VM
VP
D-
D+
tPLH_DRV tPHL_DRV
VCRS_F
VP AND VM RISE/FALL TIMES < 4ns
Figure 2. Timing of VP and VM to D+ and D-
OE
D+/D-
tPLZ_DRV tPZL_DRV
tPHZ_DRV tPZH_DRV
VP/VM CONNECTED TO GND,
D+/D- CONNECTED
TO PULLUP
VP/VM CONNECTED TO VL,
D+/D- CONNECTED
TO PULLDOWN
OE
D+/D-
Figure 3. Driver Enable and Disable Timing
+3V
0V
RCV, VM, AND VP
VL
D+/D-
tPLH_RCV,
tPLH_SE
tPHL_RCV,
tPHL_SE
INPUT RISE/FALL TIME < 4ns
Figure 4. D+/D- Timing to VP, VM, and RCV
Timing Diagrams
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
_______________________________________________________________________________________ 9
Detailed Description
The MAX3349E ±15kV ESD-protected, USB transceiver pro-
vides a full-speed USB interface to a microprocessor or
ASIC. The device supports enumeration, suspend, and
VBUS detection. A special UART multiplexing mode routes
external UART signals (Rx and Tx) to D+ and D-, allowing
the use of a shared connector to reduce cost and part count
for mobile devices.
The UART interface allows mobile devices such as PDAs,
cellular phones, and digital cameras to use either UART or
USB signaling through the same connector. The MAX3349E
features a separate UART voltage supply input. The
MAX3349E supports a maximum UART baud rate of
921kbaud.
Upon connection to a USB host, the MAX3349E enters
USB mode and provides a full-speed USB 2.0-compli-
ant interface through VP, VM, RCV, and OE. The
MAX3349E features internal series resistors on D+ and
D-, and an internal 1.5kΩpullup resistor to D+ to allow
the device to logically connect and disconnect from the
USB bus while plugged in. A suspend mode is provid-
ed for low-power operation. D+ and D- are protected
from electrostatic discharge (ESD) up to ±15kV. To
ensure full ±15kV ESD protection, bypass VBUS to GND
OE
VP/VM
VP/VM
tPLZ_SE tPZL_SE
tPHZ_SE tPZH_SE
D+/D- CONNECTED TO GND,
VP/VM CONNECTED
TO PULLUP
D+/D- CONNECTED TO +3V,
VP/VM CONNECTED
TO PULLDOWN
OE
Figure 5. Receiver Enable and Disable Timing
MAX3349E
1. ENABLE TIME (D+/D-)
MEASUREMENT
D+/D-
TEST
POINT
CL
50pF
15kΩ
2. VP/VM TO D+/D-
PROPAGATION DELAY
3. D+/D- RISE/FALL TIMES
Figure 7. Test Circuit for Enable Time, Transmitter Propagation
Delay, and Transmitter Rise/Fall Time
MAX3349E
TEST
POINT
CL
15pF
RCV/VP/VM
1. D+/D- TO RCV/VM/VP
PROPAGATION DELAYS
Figure 8. Test Circuit for Receiver Propagation Delay
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
100pF
RC
1MΩ
RD
1.5kΩ
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 9. Human Body ESD Test Model
Timing Diagrams (continued)
MAX3349E
1. DISABLE TIME (D+/D-)
MEASUREMENT
V = 0 FOR tPHZ
V = VTRM FOR tPLZ
D+/D-
TEST
POINT
CL
50pF
220Ω
Figure 6. Test Circuit for Disable Time
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
10 ______________________________________________________________________________________
with a 0.1µF ceramic capacitor as close to the device
as possible.
Operating Modes
The MAX3349E operates in either USB mode or UART
mode, depending on the presence or absence of
VBUS. Bus detect output BD is logic-high when a volt-
age higher than VTH-VBUS is applied to VBUS, and
logic-low otherwise. The MAX3349E operates in USB
mode when BD is logic-high, and UART mode when
BD is logic-low.
USB Mode
In USB mode, the MAX3349E implements a full-speed
(12Mbps) USB interface on D+ and D-, with enumerate
and suspend functions. A differential USB receiver pre-
sents the USB state as a logic-level output RCV
(Table 3a). VP/VM are outputs of single-ended USB
receivers when OE is logic-high, allowing detection of
single-ended 0 (SE0) events. When OE is logic-low, VP
and VM serve as inputs to the USB transmitter. Drive
suspend input SUS logic-high to force the MAX3349E
into a low-power operating mode and disable the differ-
ential USB receiver (Table 3b).
UART Mode
The MAX3349E operates in UART mode when BD is
logic-low (VBUS not present). The Rx signal is the out-
put of a single-ended receiver on D+, and the Tx input
is driven out on D-. Signaling voltage thresholds for D+
and D- are determined by VUART, an externally applied
voltage between +2.7V and +3.3V.
Power-Supply Configurations
V
L
Logic Supply
In both USB and UART modes, the control interface is
powered from VL. The MAX3349E operates with logic-
side voltage (VL) as low as +1.4V, providing level shift-
ing for lower voltage ASICs and microcontrollers.
Timing Diagrams (continued)
IP 100%
90%
36.8%
tRL TIME
tDL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Ir
10%
0
0
AMPERES
Figure 10. Human Body Model Current Waveform
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
150pF
RC
50MΩ to 100MΩ
RD
330Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 11. IEC61000-4-2 ESD Contact Discharge Test Model
tR = 0.7ns to 1ns 30ns
60ns
t
100%
90%
10%
I
PEAK
I
Figure 12. IEC 61000-4-2 Contact Discharge Model Current
Waveform
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
______________________________________________________________________________________ 11
USB Mode
The MAX3349E is in USB mode when VBUS is greater
than VTH-BUS and the bus detect output (BD) is logic-
high. In USB mode, power for the MAX3349E is derived
from VBUS, typically provided through the USB connec-
tor. An internal linear regulator generates the required
+3.3V VTRM voltage from VBUS. VTRM powers the inter-
nal USB transceiver circuitry and the D+ enumeration
resistor. Bypass VTRM to GND with a 1µF ceramic
capacitor as close to the device as possible. Do not
power external circuitry from VTRM.
Disable Mode
Connect VBUS to a system power supply and leave VL
unconnected or connect to ground to enter disable
mode. In disable mode, D+ and D- are high imped-
ance, and withstand external signals up to +5.5V. OE,
SUS, and control signals are ignored.
UART Mode
Connect VLand VUART to system power supplies, and
leave VBUS unconnected or below VTH-BUS to operate
the MAX3349E in UART mode. The MAX3349E sup-
ports VUART from +2.7V to +3.3V (see Table 1).
USB Control Signals
OE
OE controls the direction of communication for USB
mode. When OE is logic-low, VP and VM operate as
logic inputs, and D+/D- are outputs. When OE is logic-
high, VP and VM operate as logic outputs, and D+/D-
are inputs. RCV is the output of the differential USB
receiver connected to D+/D-, and is not affected by the
OE logic level.
ENUM
Drive ENUM logic-high to enable the internal 1.5kΩ
pullup resistor from D+ to VTRM. Drive ENUM logic-low
to disable the internal pullup resistor and logically dis-
connect the MAX3349E from the USB.
SUS
Operate the MAX3349E in low-power USB suspend
mode by driving SUS logic-high. In suspend mode, the
USB differential receiver is turned off and VBUS con-
sumes 38µA (typ) of supply current. The single-ended
VP and VM receivers remain active to detect a SE0
state on USB bus lines D+ and D-. The USB transmitter
Table 1. Power-Supply Configuration
INPUTS OUTPUTS
VP VM D+ D-
000 0
010 1
101 0
111 1
Table 2. USB Transmit Truth Table (OE = 0)
INPUTS OUTPUTS
D+ D- VP VM RCV
0000RCV*
01010
10101
1111X
Table 3a. USB Receive Truth Table (OE = 1,
SUS = 0)
INPUTS OUTPUTS
D+ D- VP VM RCV
00000
01010
10100
11110
Table 3b. USB Receive Truth Table (OE = 1,
SUS = 1)
*
= Last State
X = Undefined
VBUS(V) VTRM(V) VL(V) VUART(V) CONFIGURATION
+4.0 to +5.5 +3.0 to +3.6 Output +1.4 to +2.75 GND, Unconnected, or
+2.7V to +3.3V USB Mode
+3.0 to +5.5 +2.8 to +3.6 +1.4 to +2.75 GND or Unconnected Battery Mode
+4.0 to +5.5 +3.0 to +3.6 Output GND or Unconnected GND, Unconnected, or
+2.7V to +3.3V Disable Mode
GND or Unconnected High Impedance +1.4 to +2.75 +2.7V to +3.3V UART Mode
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
12 ______________________________________________________________________________________
remains enabled in suspend mode to allow transmis-
sion of a remote wake-up on D+ and D-.
D+ and D-
D+ and D- are either USB signals or UART signals,
depending on the operating mode. In USB mode,
D+/D- serve as receiver inputs when OE is logic-high
and transmitter outputs when OE is logic-low. Internal
series resistors are provided on D+ and D- to allow a
direct interface with a USB connector. In UART mode,
D+ is an input and D- is an output. UART signals on Tx
are presented on D-, and signals on D+ are presented
on Rx. The UART signaling levels for D+/D- are deter-
mined by VUART. Logic thresholds for Rx and Tx are
determined by VL. D+ and D- are ESD protected to
±15kV HBM.
RCV
RCV is the output of the differential USB receiver. RCV
is a logic 1 for D+ high and D- low. RCV is a logic 0 for
D+ low and D- high. RCV retains the last valid logic
state when D+ and D- are both low (SE0). RCV is driven
logic-low when SUS is high. See Tables 3a and 3b.
BD
The bus-detect (BD) output is asserted logic-high when
a voltage greater than VTH-BUS is presented on VBUS.
This is typically the case when the MAX3349E is con-
nected to a powered USB. BD is logic-low when VBUS
is unconnected.
ESD Protection
As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against electro-
static discharges encountered during handling and
assembly. Additional ESD-protection structures guard
D+ and D- against damage from ESD events up to
±15kV. The ESD structures arrest ESD events in all
operating modes: normal operation, suspend mode,
and when the device is unpowered.
Several ESD testing standards exist for gauging the
robustness of ESD structures. The ESD protection of the
MAX3349E is characterized to the following standards:
±15kV Human Body Model (HBM)
±8kV Air-Gap Discharge per IEC 61000-4-2
±8kV Contact Discharge per IEC 61000-4-2
Human Body Model
Figure 9 shows the model used to simulate an ESD
event resulting from contact with the human body. The
model consists of a 100pF storage capacitor that is
charged to a high voltage, then discharged through a
1.5kΩresistor. Figure 10 shows the current waveform
when the storage capacitor is discharged into a low
impedance.
IEC 61000-4-2 Contact Discharge
The IEC 61000-4-2 standard covers ESD testing and
performance of finished equipment. It does not specifi-
cally refer to integrated circuits. The major difference
between tests done using the Human Body Model and
IEC 61000-4-2 is a higher peak current in IEC 61000-4-
2 due to lower series resistance. Hence, the ESD with-
stand voltage measured to IEC 61000-4-2 is typically
lower than that measured using the Human Body
Model. Figure 11 shows the IEC 61000-4-2 model. The
Contact Discharge method connects the probe to the
device before the probe is charged. Figure 12 shows
the current waveform for the IEC 61000-4-2 Contact
Discharge Model.
ESD Test Conditions
ESD performance depends on a variety of conditions.
Please contact Maxim for a reliability report document-
ing test setup, methodology, and results.
Applications Information
Data Transfer in USB Mode
Transmitting Data to the USB
To transmit data to the USB, operate the MAX3349E in
USB mode (see the
Operating Modes
section), and
drive OE low. The MAX3349E transmits data to the USB
differentially on D+ and D-. VP and VM serve as differ-
ential input signals to the driver. When VP and VM are
both driven low, a single-ended zero (SE0) is output on
D+/D-.
Receiving Data from the USB
To receive data from the USB, operate the MAX3349E
in USB mode (see the
Operating Modes
section.) Drive
OE high and SUS low. Differential data received at
D+/D- appears as a logic signal at RCV. VP and VM are
the outputs of single-ended receivers on D+ and D-.
Data Transfer in UART Mode
In UART mode, D+ is an input and D- is an output.
UART signals on Tx are presented on D-, and signals
on D+ are presented on Rx. The UART signaling levels
for D+/D- are determined by VUART. The voltage
thresholds for Rx and Tx are determined by VL. The
voltage thresholds for D+ and D- are determined by
VUART.
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
______________________________________________________________________________________ 13
Power-Supply Decoupling
Bypass VBUS, VL, and VUART to ground with 0.1µF
ceramic capacitors. Additionally, bypass VTRM to
ground with a 1µF ceramic capacitor. Place all bypass
capacitors as close as possible to the device .
Power Sequencing
There are no power-sequencing requirements for VL,
VUART, and VBUS.
UCSP Application Information
For the latest application details on UCSP construction,
dimensions, tape carrier information, printed circuit-
board techniques, bump-pad layout, and recommend-
ed reflow temperature profile, as well as the latest
information on reliability testing results, refer to
the Application Note
UCSP- A Wafer-Level Chip-
Scale Package
available on Maxim’s website at
www.maxim-ic.com/ucsp.
TX 50%
D-
50%
50%
tPLH_TUART
50%
tPHL_TUART
tFR_TUART
10%
90%
10%
tFF_TUART
90%
Figure 13. UART Transmitter Timing
D+ 50%
RX
50%
50%
tPLH_RUART
50%
tPHL_RUART
tFR_RUART
10%
90%
10%
tFF_RUART
90%
Figure 14. UART Receiver Timing
Timing Diagrams
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
14 ______________________________________________________________________________________
ASIC
USB SERIAL-
INTERFACE
ENGINE (SIE)
UART
MICROCONTROLLER
VBUS
VP
VM
OE
ENUM
TX
RX
RCV
BD
VL
SUS
VTRM
D+ / RX
D- / TX
VUART
USB/UART
CONNECTOR
0.1µF
1µF
0.1µF
0.1µF
MAX3349E
Typical Operating Circuit
Chip Information
PROCESS: BiCMOS
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
16 UCSP B16+1 21-0101
Refer to
Application
Note 1891
16 TQFN-EP T1644+4 21-0139 90-0070
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
______________________________________________________________________________________ 15
3.3V
LINEAR
REGULATOR
VBUS
BD
D+
D-
RCV
VM
VP
OE
RX
TX
ENUM
VUART VTRM
1.5kΩ
VTH_VBUS
35Ω
35Ω
GND
USB
DIFFERENTIAL
TRANSMITTER
USB
RECEIVER
D-
RECEIVER
LEVEL
SHIFTING
VL
SUS
D+
RECEIVER
UART Rx
UART Tx
MAX3349E
Functional Diagram
MAX3349E
Hi-Speed USB 2.0 Full-Speed Transceiver
with UART Multiplexing Mode
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
16
____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
Revision History
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
03/06Initi al rel ease —
15/11
Added MAX3349EEBE+T to the Ordering Information and adjusted specifications in
the Electrical Characteristics 1, 2
