Datasheet MAX3349EAETE, MAX3349EA Datasheet (Maxim)

General Description

The MAX3349EA ±15kV ESD-protected, USB transceiv­er provides a full-speed USB interface to a lower voltage
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 MAX3349EA features a separate UART voltage sup­ply input to support legacy devices using +2.75V signal­ing. The MAX3349EA supports a maximum UART baud
rate of 921kbaud.

Upon connection to a USB host, the MAX3349EA enters
USB mode and provides a full-speed USB 2.0 compliant
interface through VP, VM, RCV, and OE. The
MAX3349EA features internal series termination resistors
on D+ and D-, and an internal 1.5kΩ pullup 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 MAX3349EA 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 tem­perature range.

Applications

Cell Phones

PDAs

Digital Cameras

MP3 Players

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 (V

UART

)

♦ Internal 1.5kΩ Pullup 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

♦ V

BUS

Detection

♦ Combined VP and VM Inputs/Outputs

♦ No Power-Supply Sequencing Required

♦ Available in 16-Bump UCSP (2mm x 2mm)

Package

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

________________________________________________________________ Maxim Integrated Products 1

19-0667; Rev 0; 10/06

For pricing, delivery, and ordering information, please contact Maxim/Dallas 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

V

L

V

TRM

V

BUS

D+

D-

GND

RX

TX

BD

VP

RCV

OE

SUS

V

UART

MAX3349EA

TOP VIEW

*EP

+

UCSP (2mm x 2mm)

(BUMPS ON BOTTOM OF DIE)

MAX3349EA

TOP VIEW

A

B

C

1

23

RX

TX

V

UART

VP

V

L

ENUM

SUS

V

TRM

BD

VM

RCV

OE

4

D

D+

D-

V

BUS

GND

*EXPOSED PADDLE—CONNECT TO GND OR LEAVE UNCONNECTED.

+

+ DENOTES LEAD-FREE PACKAGE.

Pin Configurations

UCSP is a trademark of Maxim Integrated Products, Inc.

Note: All devices specified for the -40°C to +85°C extended
temperature range.

**Future product—contact factory for availability.
*EP = Exposed paddle.
+Indicates lead-free package.

PART PIN-PACKAGE PKG CODE

MAX3349EAEBE+T 16 UCSP B16-1

MAX3349EAETE** 16 TQFN-EP* T1644-4

MAX3349EA

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.)
V

UART

, VL, V

BUS

, D+, D- ..........................................-0.3V to +6V

V

TRM

.........................................................-0.3V to (V

BUS

+ 0.3V)

VP, VM, SUS, RX, TX, ENUM, RCV, OE, BD, -0.3V to (V

L

+ 0.3V)

Short Circuit Current (D+ and D-)...................................±150mA

Maximum Continuous Current (all other pins) .................±15mA

Continuous Power Dissipation (T

A

= +70°C)

16-Bump UCSP (derate 8.2mW/°C above +70°C) ....659.5mW

16-Pin 4mm x 4mm 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

ELECTRICAL CHARACTERISTICS

(V

BUS

= +4.0V to +5.5V, V

UART

= +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 V

BUS

= +5V, VL= +1.8V, V

UART

= +2.75V (UART Mode), and TA= +25°C.) (Note 1)

PARAMETER SYMBOL CONDITIONS

MIN

TYP

MAX

UNITS

SUPPLY INPUTS/OUTPUTS (V

BUS

, V

UART

, V

TRM

, VL)

V

BUS

Input Range V

BUS

USB mode 4.0 5.5 V

VL Input Range V

L

V

V

UART

Input Range V

UART

UART mode 2.7 3.3 V

Regulated Supply-Voltage Output

V

TRM

Internal regulator, USB mode 3.0 3.6 V

Operating V

BUS

Supply Current I

BUS

Full-speed transmitting/receiving at
12Mbps, C

L

= 50pF on D+ and D-

10 mA

Operating V

UART

Supply Current

I

VUART

UART transmitting/receiving at
921kbaud, C

L

= 200pF

2.5 mA

Static V

UART

Supply Current

)

UART mode 3.5 5 µA

Operating VL Supply Current I

VL

Full-speed transmitting/receiving at
12Mbps, C

L

= 50pF on D+ and D-

6mA

Full-speed idle,
V

D+

> +2.7V, V

D-

< +0.3V

400

Full-Speed Idle and SE0 Supply
Current

I

VBUS(IDLE)

SE0: VD+ < +0.3V, VD- < +0.3V

450

µA

Static VL Supply Current I

VL(STATIC)

Full-speed idle, SE0, suspend mode, or
static UART mode

210µA

Sharing Mode VL Supply Current

I

VL(OFF)

V

BUS

and V

UART

not present 2 5 µA

USB Suspend V

BUS

Supply

Current

I

VBUS(SUS)

VM, VP unconnected;
OE = 1, SUS = 1

38 65 µA

V

BUS

DETECTION (BD)

VL = +1.8V 1.8 2.7 3.4

USB Power-Supply Detection
Threshold

V

TH_VBUS

VL = +2.5V 2.3 3.2 4.0

V

VL = +1.8V 80

USB Power-Supply Detection
Hysteresis

V

HYS_VBUS

VL = +2.5V

mV

VL Power-Supply Detection
Threshold

V

TH_VL

0.7 V

1.40 2.75

I

VUART(STATIC

290

340

100

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(V

BUS

= +4.0V to +5.5V, V

UART

= +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 V

BUS

= +5V, VL= +1.8V, V

UART

= +2.75V (UART Mode), and TA= +25°C.) (Note 1)

PARAMETER SYMBOL CONDITIONS

UNITS

V

UART

Power-Supply Detection

Threshold

V

TH_UART

0.4 x
V

L

0.65 x
V

L

0.9 x
V

L

V

DIGITAL INPUTS/OUTPUTS (VP, VM, RCV, SUS, OE, RX, TX, ENUM, BD)

Input Voltage Low V

IL

0.3 x
V

L

V

Input Voltage High V

IH

0.7 x
V

L

V

Output Voltage Low V

OL

IOL = +2mA, VL > 1.65V
I

OL

= +1mA, VL < 1.65V

0.4 V

Output Voltage High V

OH

IOH = +2mA, VL > 1.65V
I

OH

= +1mA, VL < 1.65V

V

L

­V

Input Leakage Current I

LKG

-1 +1 µA

ANALOG INPUTS/OUTPUTS (D+, D- in USB Mode)

Differential Input Sensitivity V

ID

|VD+ - VD-| 0.2 V

Differential Common-Mode
Voltage

V

CM

Includes V

ID

range 0.8 2.5 V

Single-Ended Input
Low Voltage

V

ILSE

0.8 V

Single-Ended Input
High Voltage

V

IHSE

2.0 V

USB Output Voltage Low V

USB_OLD

RL = 1.5kΩ connected to +3.6V 0.3 V

USB Output Voltage High V

USB_OHD

RL = 15kΩ connected to GND 2.8 3.6 V

Off-State Leakage Current I

LZ

-10

µA

Driver Output Impedance Z

DRV

Steady-state drive

38

Ω

Transceiver Capacitance C

IND

Measured from D+/D- to GND 20 pF

Input Impedance Z

IN

Driver off 0.9 1.3 2.0 MΩ

D+ Internal Pullup Resistor R

PU

ENUM = 1

Ω

ANALOG INPUTS/OUTPUTS (D+, D- in UART Mode)

Input Voltage High V

UART_IH

2.0 V

Input Voltage Low V

UART_IL

UART mode,
+2.70V < V

UART

< +2.85V

0.8 V

Output Voltage High V

UART_OH

UART mode,
+2.70V < V

UART

< +2.85V

I

UART_OH

= -2mA

2.2 V

Output Voltage Low V

UART_OL

UART mode,
+2.70V < V

UART

< +2.85V

I

UART_OL

= +2mA

0.4 V

UART mode, +2.70 < V

MIN TYP MAX

0.4

29.0

1425 1500 1575

< +2.85V

UART

+10

43.5

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART
Multiplexing Mode

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(V

BUS

= +4.0V to +5.5V, V

UART

= +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 V

BUS

= +5V, VL= +1.8V, V

UART

= +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)

kV

IEC 61000-4-2
Air-Gap Discharge

±8 kV

IEC 61000-4-2
Contact Discharge

±8 kV

TIMING CHARACTERISTICS

(V

BUS

= +4.0V to +5.5V, V

UART

= +2.7V to +3.3V, VL= +1.4V to +2.75V, TA= -40°C to +85°C, unless otherwise noted. Typical values

are at V

BUS

= +5V, VL= +1.8V, V

UART

= +2.75V (UART Mode), and TA= +25°C.) (Note 1)

PARAMETER SYMBOL CONDITIONS

UNITS

USB DRIVER CHARACTERISTICS (CL = 50pF)

Rise Time t

FR

10% to 90% of | V

USB_OHD

- V

USB_OLD

|

(Figures 1 and 7)

420ns

Fall Time t

FF

90% to 10% of | V

USB_OHD

- V

USB_OLD

|

(Figures 1 and 7)

420ns

Rise/Fall Time Matching tFR/t

FF

Excluding the first transition from idle
state (Note 2) (Figures 1 and 7)

90

%

Output Signal Crossover Voltage

V

CRS_F

Excluding the first transition from idle
state (Note 2) (Figure 2)

1.3 2.0 V

VL > +1.65V (Figures 2 and 7)

t

PLH_DRV

+1.4V < VL < +1.65V (Figures 2 and 7) 25

VL > +1.65V (Figures 2 and 7)

Driver Propagation Delay

t

PHL_DRV

+1.4V < VL < +1.65V (Figures 2 and 7) 25

ns

t

PHZ_DRV

High-to-off transition (Figures 3 and 6) 25

Driver Disable Delay

t

PLZ_DRV

Low-to-off transition (Figures 3 and 6) 25

ns

t

PZH_DRV

Off-to-high transition (Figures 3 and 7) 25

Driver Enable Delay

t

PZL_DRV

Off-to-low transition (Figures 3 and 7) 25

ns

USB RECEIVER CHARACTERISTICS (CL = 15pF)

VL > +1.65V (Figures 4 and 8) 25

t

PLH_RCV

+1.4V < VL < +1.65V (Figures 4 and 8) 30

VL > +1.65V (Figures 4 and 8) 25

Differential Receiver Propagation
Delay

t

PHL_RCV

1.4V < VL < +1.65V (Figures 4 and 8) 30

ns

VL > +1.65V (Figures 4 and 8) 28

t

PLH_SE

+1.4V < VL < +1.65V (Figures 4 and 8) 35

VL > +1.65V (Figures 4 and 8) 28

Single-Ended Receiver
Propagation Delay

t

PHL_SE

+1.4V < VL < +1.65V (Figures 4 and 8) 35

ns

MIN TYP MAX

±15

110

22.5

22.5

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

_______________________________________________________________________________________ 5

TIMING CHARACTERISTICS (continued)

(V

BUS

= +4.0V to +5.5V, V

UART

= +2.7V to +3.3V, VL= +1.4V to +2.75V, TA= -40°C to +85°C, unless otherwise noted. Typical values

are at V

BUS

= +5V, VL= +1.8V, V

UART

= +2.75V (UART Mode), and TA= +25°C.) (Note 1)

PARAMETER SYMBOL CONDITIONS

MIN

TYP

MAX

UNITS

High-to-off transition,
V

L

> +1.65V (Figure 5)

10

t

PHZ_SE

High-to-off transition,
+1.4V < V

L

< +1.65V (Figure 5)

12

Low-to-off transition,
V

L

> +1.65V (Figure 5)

10

Single-Ended Receiver Disable
Delay

t

PLZ_SE

Low-to-off transition,
+1.4V < V

L

< +1.65V (Figure 5)

12

ns

Off-to-high transition,
V

L

> +1.65V (Figure 5)

20

t

PZH_SE

Off-to-high transition,
+1.4V < V

L

< +1.65 (Figure 5)

20

Off-to-low transition,
V

L

> +1.65V (Figure 5)

20

Single-Ended Receiver Enable
Delay

t

PZL_SE

Off-to-low transition,
+1.4V < V

L

< +1.65V (Figure 5)

20

ns

UART DRIVER CHARACTERISTICS (CL = 200pF)

Rise Time (D-) t

FR_TUART

60

ns

Fall Time (D-) t

FF_TUART

60

ns

(Figure 13) 70

Driver Propagation Delay

(Figure 13) 70

ns

UART RECEIVER CHARACTERISTICS (CL = 15pF)

(Figure 14) 60

Receiver (Rx) Propagation Delay

(Figure 14) 60

ns

t

FR_RUART

(Figure 14) 45

Receiver (Rx) Rise/Fall Time

t

FF_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.

10% to 90% of |V

90% to 10% of |V

t

PLH_TUART

t

PHL_TUART

t

PLH_RUART

t

PHL_RUART

OHD

OHD

- V

- V

| (Figure 13)

OLD

| (Figure 13)

OLD

200

200

200

200

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART
Multiplexing Mode

6 _______________________________________________________________________________________

Typical Operating Characteristics

(V

BUS

= +5V, VL= +3.3V, V

UART

= +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. V

L

MAX3349EA 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. V

BUS

MAX3349EA toc02

V

BUS

(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

MAX3349EA toc03

VL (V)

I

VL

(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

V

BUS

CURRENT CONSUMPTION

IN SUSPEND MODE

MAX3349EA toc04

V

BUS

(V)

I

VCC

(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

MAX3349EA toc05

D+/D- CAPACITANCE (CL)

I

VL

(mA)

12Mbps DATA RATE
TRANSMITTING

0

4

12

8

16

20

08040 120 160 200 240

V

BUS

CURRENT DURING USB OPERATION

vs. D+/D- CAPACITANCE

MAX3349EA toc06

D+/D- CAPACITANCE (CL)

I

VBUS

(mA)

12Mbps DATA RATE
TRANSMITTING

10ns/div

SUSPEND MODE

RCV
2V/div

SUS
2V/div

MAX3349EA toc07

4µs/div

BUS DETECT RESPONSE

BD
1V/div

V

BUS

2V/div

MAX3349EA toc08

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

_______________________________________________________________________________________ 7

Pin Description

PIN

UCSP

TYPE NAME FUNCTION

A1 1

V

UART

UART Supply Voltage. V

UART

powers the internal UART transmitter and receiver.

Connect a regulated voltage between +2.7V and +3.3V to V

UART

. Bypass V

UART

to

GND with a 0.1µF ceramic capacitor.

A2 2

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

BD

USB Detect Output. When V

BUS

exceeds the V

TH-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 logic­low.

B1 15

V

L

Digital 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 = V

L

. 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 = V

L

. VP

follows the logic state of D+ when receiving. VP functions as a driver input when OE
= GND (Tables 2 and 3).

B4 6

RCV

Differential Receiver Output. In USB mode, RCV is the output of the USB differential
receiver (Table 3).

C1 14

V

TRM

Internal Regulator Output. V

TRM

provides a regulated +3.3V output. Bypass V

TRM

to

GND with a 1µF ceramic capacitor. V

TRM

draws power from V

BUS

. Do not power

external circuitry from V

TRM

.

C2 13 INPUT ENUM

Enumerate Input. Drive ENUM to V

L

to connect the internal 1.5kΩ resistor from D+ to

V

TRM

(when V

BUS

is present). Drive ENUM to GND to disconnect the internal 1.5kΩ

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

V

BUS

USB Supply Voltage. V

BUS

provides power to the internal linear regulator when in

USB mode. Bypass V

BUS

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

GND Ground

—EP— EP Exposed Paddle. Connect exposed paddle to GND.

TQFN

POWER

OUTPUT

OUTPUT

POWER

OUTPUT

POWER

POWER

POWER

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART
Multiplexing Mode

8 _______________________________________________________________________________________

90%

10%

90%

10%

t

FR

, t

FR_TUART

tFF, t

FF_TUART

V

USB_OLD

, V

OLD

V

USB_OHD

, V

OHD

Figure 1. Rise and Fall Times

VM

VP

D-

D+

t

PLH_DRV

t

PHL_DRV

V

CRS_F

VP AND VM RISE/FALL TIMES < 4ns

Figure 2. Timing of VP and VM to D+ and D-

OE

D+/D-

t

PLZ_DRV

t

PZL_DRV

t

PHZ_DRV

t

PZH_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

V

L

D+/D-

t

PLH_RCV

,

t

PLH_SE

t

PHL_RCV

,

t

PHL_SE

INPUT RISE/FALL TIME < 4ns

Figure 4. D+/D- Timing to VP, VM, and RCV

Timing Diagrams

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

_______________________________________________________________________________________ 9

Detailed Description

The MAX3349EA ±15kV ESD-protected, USB transceiver
provides a full-speed USB interface to a microprocessor or
ASIC. The device supports enumeration, suspend, and
V

BUS

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
MAX3349EA features a separate UART voltage supply

input. The MAX3349EA supports a maximum UART
baud rate of 921kbaud.

Upon connection to a USB host, the MAX3349EA
enters USB mode and provides a full-speed USB 2.0
compliant interface through VP, VM, RCV, and OE. The
MAX3349EA features internal series resistors on D+
and D-, and an internal 1.5kΩ pullup resistor to D+ to
allow the device to logically connect and disconnect
from the USB bus while plugged in. A suspend mode is
provided for low-power operation. D+ and D- are pro­tected from electrostatic discharge (ESD) up to ±15kV.
To ensure full ±15kV ESD protection, bypass V

BUS

to

OE

VP/VM

VP/VM

t

PLZ_SE

t

PZL_SE

t

PHZ_SE

t

PZH_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

MAX3349EA

1. ENABLE TIME (D+/D-)
MEASUREMENT

D+/D-

TEST

POINT

C

L

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

MAX3349EA

TEST

POINT

C

L

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

C

s

100pF

R

C

1MΩ

R

D

1.5kΩ

HIGH-

VOLTAGE

DC

SOURCE

DEVICE
UNDER

TEST

Figure 9. Human Body ESD Test Model

Timing Diagrams (continued)

MAX3349EA

1. DISABLE TIME (D+/D-)
MEASUREMENT

V = 0 FOR t

PHZ

V = V

TRM

FOR t

PLZ

D+/D-

TEST

POINT

C

L

50pF

220Ω

Figure 6. Test Circuit for Disable Time

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART
Multiplexing Mode

10 ______________________________________________________________________________________

GND with a 0.1µF ceramic capacitor as close to the
device as possible. There are high-impedance resistors
~2MΩ to ground on D+ and D- to prevent floating
nodes when in UART mode and nothing is connected.

Operating Modes

The MAX3349EA operates in either USB mode or
UART mode, depending on the presence or absence
of V

BUS

. Bus detect output BD is logic-high when a

voltage higher than V

TH-VBUS

is applied to V

BUS

, and
logic-low otherwise. The MAX3349EA operates in USB
mode when BD is logic-high, and UART mode when
BD is logic-low.

USB Mode

In USB mode, the MAX3349EA implements a full-speed
(12Mbps) USB interface on D+ and D-, with enumerate
and suspend functions. A differential USB receiver pre­sents 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 single­ended 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 MAX3349EA into
a low-power operating mode and disable the differen­tial USB receiver (Table 3b).

UART Mode

The MAX3349EA operates in UART mode when BD is
logic-low (V

BUS

not present). The Rx signal is the out­put 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 V

UART

, an externally applied

voltage between +2.7V and +3.3V.

Power-Supply Configurations

VLLogic Supply

In both USB and UART modes, the control interface is
powered from VL. The MAX3349EA operates with logic­side voltage (VL) as low as +1.4V, providing level shift­ing for lower voltage ASICs and microcontrollers.

Timing Diagrams (continued)

IP 100%

90%

36.8%

t

RL

TIME

t

DL

CURRENT WAVEFORM

PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)

I

r

10%

0

0

AMPERES

Figure 10. Human Body Model Current Waveform

CHARGE-CURRENT-

LIMIT RESISTOR

DISCHARGE

RESISTANCE

STORAGE
CAPACITOR

C

s

150pF

R

C

50MΩ to 100MΩ

R

D

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

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

______________________________________________________________________________________ 11

USB Mode

The MAX3349EA is in USB mode when V

BUS

is greater

than V

TH-BUS

and the bus detect output (BD) is logic­high. In USB mode, power for the MAX3349EA is
derived from V

BUS

, typically provided through the USB
connector. An internal linear regulator generates the
required +3.3V V

TRM

voltage from V

BUS

. V

TRM

powers
the internal USB transceiver circuitry and the D+ enu­meration resistor. Bypass V

TRM

to GND with a 1µF
ceramic capacitor as close to the device as possible.
Do not power external circuitry from V

TRM

.

Disable Mode

Connect V

BUS

to a system power supply and leave V

L

unconnected or connect to ground to enter disable
mode. In disable mode, D+ and D- are high imped­ance, and withstand external signals up to +5.5V. OE,
SUS, and control signals are ignored.

UART Mode

Connect VLand V

UART

to system power supplies, and

leave V

BUS

unconnected or below V

TH-BUS

to operate
the MAX3349EA in UART mode. The MAX3349EA sup­ports V

UART

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 logic­high, VP and VM operate as logic outputs, and D+/D­are 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 V

TRM

. Drive ENUM logic-low
to disable the internal pullup resistor and logically dis­connect the MAX3349EA from the USB.

SUS

Operate the MAX3349EA in low-power USB suspend
mode by driving SUS logic-high. In suspend mode, the
USB differential receiver is turned off and V

BUS

con­sumes 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
remains enabled in suspend mode to allow transmis­sion of a remote wake-up on D+ and D-.

V

BUS

(V) V

TRM

(V) VL(V) V

UART

(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

+4.0 to +5.5 +3.0 to +3.6 Output

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

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.

GND or Unconnected

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART
Multiplexing Mode

12 ______________________________________________________________________________________

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 deter­mined by V

UART

. 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 V

TH-BUS

is presented on V

BUS

.
This is typically the case when the MAX3349EA is con­nected to a powered USB. BD is logic-low when V

BUS

is unconnected.

ESD Protection

As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against electro­static 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
MAX3349EA 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

1.5kΩ resistor. 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 specifi­cally 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 with­stand 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 document­ing 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 MAX3349EA in
USB mode (see the Operating Modes section), and
drive OE low. The MAX3349EA transmits data to the
USB differentially on D+ and D-. VP and VM serve as
differential 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 MAX3349EA
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 V

UART

. The voltage
thresholds for Rx and Tx are determined by VL. The
voltage thresholds for D+ and D- are determined by
V

UART

.

Power-Supply Decoupling

Bypass V

BUS

, VL, and V

UART

to ground with 0.1µF

ceramic capacitors. Additionally, bypass V

TRM

to
ground with a 1µF ceramic capacitor. Place all bypass
capacitors as close as possible to the device .

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

______________________________________________________________________________________ 13

Power Sequencing

There are no power-sequencing requirements for VL,
V

UART

, and V

BUS

.

UCSP Application Information

For the latest application details on UCSP construction,
dimensions, tape carrier information, printed circuit­board techniques, bump-pad layout, and recommend­ed 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%

t

PLH_TUART

50%

t

PHL_TUART

t

FR_TUART

10%

90%

10%

t

FF_TUART

90%

Figure 13. UART Transmitter Timing

D+

50%

RX

50%

50%

t

PLH_RUART

50%

t

PHL_RUART

t

FR_RUART

10%

90%

10%

t

FF_RUART

90%

Figure 14. UART Receiver Timing

Timing Diagrams

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART
Multiplexing Mode

14 ______________________________________________________________________________________

ASIC

USB SERIAL-

INTERFACE

ENGINE (SIE)

UART

MICROCONTROLLER

V

BUS

VP

VM

OE

ENUM

TX

RX

RCV

BD

V

L

SUS

V

TRM

D+ / RX

D- / TX

V

UART

USB/UART

CONNECTOR

0.1µF

1µF

0.1µF

0.1µF

MAX3349EA

Typical Operating Circuit

Chip Information

PROCESS: BiCMOS

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART

Multiplexing Mode

______________________________________________________________________________________ 15

3.3V

LINEAR

REGULATOR

V

BUS

BD

D+

D-

RCV

VM

VP

OE

RX

TX

ENUM

V

UART

V

TRM

1.5kΩ

VTH_VBUS

38Ω

38Ω

GND

USB
DIFFERENTIAL
TRANSMITTER

USB

RECEIVER

D-

RECEIVER

LEVEL

SHIFTING

V

L

SUS

D+

RECEIVER

UART Rx

UART Tx

Functional Diagram

MAX3349EA

USB 2.0 Full-Speed Transceiver with UART
Multiplexing Mode

16 ______________________________________________________________________________________

Package Information

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages

.)

16L,UCSP.EPS

PACKAGE OUTLINE, 4x4 UCSP

21-0101

1

H

1

MAX3349EA

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.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 17

© 2006 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.

Package Information (continued)

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages

.)

24L QFN THIN.EPS

PACKAGE OUTLINE,

21-0139

2

1

E

12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm

PACKAGE OUTLINE,

21-0139

2

2

E

12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm