19-2843; Rev 2; 10/08
±15kV ESD-Protected USB Transceivers
The MAX3450E/MAX3451E/MAX3452E USB-compliant
transceivers interface low-voltage ASICs with USB
devices. The devices fully comply with USB 1.1 and
USB 2.0 when operating at full (12Mbps) and low
(1.5Mbps) speeds. The MAX3450E/MAX3451E/
MAX3452E operate with VL as low as +1.65V, ensuring
compatibility with low-voltage ASICs.
The MAX3450E/MAX3451E/MAX3452E feature a logicselectable suspend mode that reduces current consumption to less than 40µA. Integrated ±15kV ESD
protection protects the USB D+ and D- bidirectional
bus connections. The MAX3450E is pin compatible with
Micrel’s MIC2550A. The MAX3451E features an internal
1.5kΩ USB pullup resistor and an enumeration function
that allows devices to logically disconnect while
plugged in. The MAX3452E provides a push-pull busdetect (BD) output that asserts high when V BUS is
greater than +4.0V.
The MAX3450E/MAX3451E/MAX3452E operate over the
-40°C to +85°C extended temperature range and are
available in 14-pin TSSOP and 3mm x 3mm 16-pin Thin
QFN packages.
Applications
PDAs
PC Peripherals
Features
♦ ±15kV ESD Protection on D+ and D♦ Combined VP and VM Inputs/Outputs
♦ +1.65V to +3.6V VL Logic Supply Input for
Interfacing with Low-Voltage ASICs
♦ Enumerate Input Function (MAX3451E)
♦ Powered from Li+ Battery as Low as +3.1V
(MAX3450E and MAX3451E)
♦ VBUS Detection (MAX3452E)
♦ Pin Compatible with Micrel MIC2550A (MAX3450E)
♦ Internal D+ or D- Pullup Resistor (MAX3451E)
♦ No Power-Supply Sequencing Required
Ordering Information
PART
PIN-PACKAGE
MAX3450EEUD+
14 TSSOP
MAX3450EETE+
16 Thin QFN-EP†
—
MAX3451EEUD+
14 TSSOP
MAX3451EETE+
16 Thin QFN-EP†
MAX3452EEUD+
14 TSSOP
MAX3452EETE+
Cellular Telephones
16 Thin
TOP MARK
AAJ
—
AAK
—
QFN-EP†
AAL
Note: All devices are specified over the -40°C to +85°C operating temperature range.
+Denotes lead(Pb)-free package/RoHS-compliant package.
†EP = Exposed pad.
Data Cradles
MP3 Players
Typical Operating Circuit appears at end of data sheet.
RCV 3
12 VTRM
VP 4
VM 5
MAX3450E
MAX3451E
MAX3452E
SPD
1
RCV
2
VP
3
N.C.
*(ENUM)
**(BD)
15
14
13
12 VTRM
MAX3450E
MAX3451E
MAX3452E
11 D+
10 D-
N.C. 6
9 OE
GND 7
8 SUS
TSSOP
*MAX3451E ONLY
**MAX3452E ONLY
***CONNECT EXPOSED PADDLE TO GND OR LEAVE UNCONNECTED
11 D+
10 D-
***EXPOSED PAD
VM
4
9
5
6
7
8
N.C.
13 N.C. *(ENUM) **(BD)
16
SUS
SPD 2
+
VBUS
14 VBUS
GND
+
N.C.
VL 1
VL
TOP VIEW
N.C.
Pin Configurations
OE
3mm x 3mm
THIN QFN-EP
________________________________________________________________ Maxim Integrated Products
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.
1
MAX3450E/MAX3451E/MAX3452E
General Description
MAX3450E/MAX3451E/MAX3452E
±15kV ESD-Protected USB Transceivers
ABSOLUTE MAXIMUM RATINGS
VBUS, VL, D+, D- to GND.......................................-0.3V to +6.0V
VTRM to GND ............................................-0.3V to (VBUS + 0.3V)
VP, VM, SUS, SPD, ENUM,
RCV, OE, BD to GND ................................-0.3V to (VL + 0.3V)
Current (into any pin)........................................................±15mA
Short-Circuit Current (D+ and D-) ..................................±150mA
Continuous Power Dissipation (TA = +70°C)
14-Pin TSSOP
(derate 10mW/°C above +70°C) ..................................797mW
16-Pin Thin QFN-EP 3mm x 3mm
(derate 20.8mW/°C above +70°C) .............................1667mW
Package Junction-to-Ambient Thermal Resistance (θJA) (Note 1)
14-Pin TSSOP..........................................................100.4°C/W
16-Pin Thin QFN-EP .....................................................48°C/W
Package Junction-to-Case Thermal Resistance (θJC) (Note 1)
14-Pin TSSOP...............................................................30°C/W
16-Pin Thin QFN-EP .......................................................7°C/W
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
Note 1: Package thermal resistances were obtained using the method described in JEDEC specifications. For detailed information
on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
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.
DC ELECTRICAL CHARACTERISTICS
(VBUS = +4.0V to +5.5V or VTRM = +3.0V to +3.6V, VL = +1.65V to +3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values
are at VBUS = +5.0V, VL = +2.5V, and TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
3.0
3.3
3.6
V
SUPPLY INPUTS (VBUS, VTRM, VL)
Regulated Supply Voltage
Output
VTRM
Internal regulator
Operating Supply Current
IVBUS
Full-speed transmitting/receiving at 12Mbps,
CL = 50pF on D+ and D- (Note 3)
10
mA
IVL
Full-speed transmitting/receiving at 12Mbps
(Note 3)
2.5
mA
Operating VL Supply Current
Full-Speed Idle and SE0 Supply
Current
IVBUS(IDLE)
Static VL Supply Current
IVL(STATIC)
Suspend Supply Current
Full-speed idle: VD+ > 2.7V, VD- < 0.3V
250
350
SE0: VD+ < 0.3V, VD- < 0.3V
250
350
Full-speed idle,
SE0, or suspend
mode
MAX3450E,
MAX3451E
5
MAX3452E
15
IVBUS(SUSP)
VM = VP = open,
SUS = OE = high
MAX3450E,
MAX3451E
(ENUM = low)
35
IVBUS(DIS)
VL = GND or open
MAX3452E
Disable-Mode Supply Current
Sharing-Mode VL Supply
Current
D+/D- Sharing-Mode
Load Current
D+/D- Disable-Mode
Load Current
2
VBUS = GND or open,
OE = low, VP = low or
IVL(SHARING)
high, VM = low or
high, SUS = high
µA
µA
40
20
MAX3450E,
MAX3451E
5
MAX3452E
20
µA
µA
ID_(SHARING) VBUS = GND or open, VD_ = 0 or +5.5V
ID_(DIS)
µA
VL = GND or open, VD_ = 0 or +5.5V
_______________________________________________________________________________________
20
µA
5
µA
±15kV ESD-Protected USB Transceivers
(VBUS = +4.0V to +5.5V or VTRM = +3.0V to +3.6V, VL = +1.65V to +3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values
are at VBUS = +5.0V, VL = +2.5V, and TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX3450E/MAX3451E, supply lost
USB Power-Supply Detection
Threshold
VTH_VBUS
MAX3450E/MAX3451E, supply present (Note 4)
VL Power-Supply Detection
Threshold
VHYST_VBUS
UNITS
0.8
3.6
MAX3452E, supply lost
MAX3452E, supply present
USB Power-Supply Detection
Hysteresis
MAX
3.6
V
4.0
MAX3450E/MAX3451E
75
MAX3452E
40
VTH_VL
mV
0.85
V
DIGITAL INPUTS/OUTPUTS (VP, VM, RCV, SUS, OE, SPD, BD, ENUM)
Input Voltage Low
VIL
VM, VP, SUS, SPD, ENUM, OE
Input Voltage High
VIH
VM, VP, SUS, SPD, ENUM, OE
Output Voltage Low
VOL
VM, VP, RCV, BD, IOL = +2mA
Output Voltage High
VOH
VM, VP, RCV, BD, IOH = -2mA
Input Leakage Current
ILKG
Input Capacitance
CIN
Measured from input to GND
Differential Input Sensitivity
VID
|VD+ - VD-|
0.2
Differential Common-Mode
Voltage
VCM
Includes VID range
0.8
Single-Ended Input Low Voltage
VILSE
Single-Ended Input High Voltage
VIHSE
Hysteresis
VHYST
Output Voltage Low
VOLD
RL = 1.5kΩ to +3.6V
Output Voltage High
VOHD
RL = 15kΩ to GND
0.3 x VL
0.7 x VL
V
V
0.4
V
+1
µA
VL - 0.4
V
-1
10
pF
ANALOG INPUTS/OUTPUTS (D+, D-)
ILZ
CIND
Measured from D_ to GND
Driver Output Impedance
ZDRV
Steady-state drive
ZIN
RPULLUP
V
0.8
V
V
250
Transceiver Capacitance
Internal Pullup Resistance
2.5
2.0
Off-State Leakage Current
Input Impedance
V
2.8
-1
Driver off
ILOAD = 500µA (MAX3451E) (Note 5)
mV
0.3
V
3.6
V
+1
µA
20
4.0
pF
15.5
Ω
MΩ
10
1.425
1.575
kΩ
ESD PROTECTION (D+, D-)
Human Body Model
±15
kV
IEC 1000-4-2 Contact Discharge
±8
kV
_______________________________________________________________________________________
3
MAX3450E/MAX3451E/MAX3452E
DC ELECTRICAL CHARACTERISTICS (continued)
MAX3450E/MAX3451E/MAX3452E
±15kV ESD-Protected USB Transceivers
TIMING CHARACTERISTICS
(VBUS = +4.0V to +5.5V or VTRM = +3.0V to +3.6V, VL = +1.65V to +3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values
are at VBUS = +5V, VL = +2.5V, and TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DRIVER CHARACTERISTICS (FULL-SPEED MODE, CL = 50pF)
Rise Time
tFR
10% to 90% of |VOHD - VOLD|, Figures 1, 6
4
20
ns
Fall Time
tFF
90% to 10% of |VOHD - VOLD|, Figures 1, 6
4
20
ns
Rise-/Fall-Time Matching
(Note 3)
tFR/tFF
Excluding the first transition from idle state,
(Figures 1, 6)
90
110
%
Output-Signal Crossover
Voltage (Note 3)
VCRS_F
Excluding the first transition from idle state,
(Figures 2, 6)
1.3
2.0
V
tPLH_DRV
Low-to-high transition
18
tPHL_DRV
High-to-low transition
18
Driver Disable Delay
(Figure 3)
tPHZ_DRV
High-to-off transition
20
tPLZ_DRV
Low-to-off transition
20
Driver Enable Delay
(Figure 3)
tPZH_DRV
Off-to-high transition
20
tPZL_DRV
Off-to-low transition
20
Driver Propagation Delay
(Figures 2, 6)
ns
ns
ns
DRIVER CHARACTERISTICS (LOW-SPEED MODE, CL = 200pF TO 600pF)
Rise Time
tLR
10% to 90% of |VOHD - VOLD|, Figures 1, 6
75
300
ns
Fall Time
tLF
90% to 10% of |VOHD - VOLD|, Figures 1, 6
75
300
ns
Rise-/Fall-Time Matching
tLR/tLF
Excluding the first transition from idle state,
Figures 1, 6
80
125
%
Output-Signal Crossover
Voltage
VCRS_L
Excluding the first transition from idle state,
Figures 2, 6
1.3
2.0
V
RECEIVER CHARACTERISTICS (CL = 15pF)
Differential Receiver Propagation
Delay, Figures 4, 6
tPLH_RCV
Low-to-high transition
22
tPHL_RCV
High-to-low transition
22
Single-Ended Receiver
Propagation Delay, Figures 4, 6
tPLH_SE
Low-to-high transition
12
tPHL_SE
High-to-low transition
12
Single-Ended Receiver Disable
Delay, Figure 5
tPHZ_SE
High-to-off transition
15
tPLZ_SE
Low-to-off transition
15
Single-Ended Receiver Enable
Delay, Figure 5
tPZH_SE
Off-to-high transition
15
tPZL_SE
Off-to-low transition
15
Note 2: Parameters are 100% production tested at +25°C, unless otherwise noted. Limits over temperature are guaranteed by
design.
Note 3: Guaranteed by design, not production tested.
Note 4: Production tested to +2.7V for VL ≤ +3.0V.
Note 5: Including external 24.3Ω series resistor.
4
_______________________________________________________________________________________
ns
ns
ns
ns
±15kV ESD-Protected USB Transceivers
SINGLE-ENDED RECEIVER
PROPAGATION DELAY vs. VL
MAX3450-52E toc01
CL = 15pF
7
TA = +25°C
CL = 400pF
CL = 50pF
TA = +85°C
5
D+/D1V/div
D+/D1V/div
4
TA = -40°C
3
2
1
0
1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6
20ns/div
100ns/div
SUPPLY CURRENT
vs. D+/D- CAPACITANCE
LOGIC SUPPLY CURRENT
vs. D+/D- CAPACITANCE
VL (V)
VM
2V/div
OE
5V/div
SPD = VL, fIN = 6MHz
SPD = GND, fIN = 750kHz
4
2
450
400
350
SPD = VL, fIN = 6MHz
300
250
200
150
SPD = GND, fIN = 750kHz
100
50
0
20ns/div
500
MAX3450-52E toc06
VP
2V/div
24
22
20
18
16
14
12
10
8
6
MAX3450-52E toc05
MAX3450-52E toc04
CL = 15pF
LOGIC SUPPLY CURRENT (μA)
OE, VP, AND VM TIMING
SUPPLY CURRENT (mA)
PROPAGATION DELAY (ns)
MAX3450-52E toc03
MAX3450-52E toc02
8
6
RISE-/FALL-TIME MATCHING
(LOW SPEED)
RISE-/FALL-TIME MATCHING
(FULL SPEED)
0
0
50
100 150 200 250 300 350 400
D+/D- CAPACITANCE (pF)
0
50
100 150 200 250 300 350 400
D+/D- CAPACITANCE (pF)
_______________________________________________________________________________________
5
MAX3450E/MAX3451E/MAX3452E
Typical Operating Characteristics
(VBUS = +5.0V, VL = +3.3V, TA = +25°C, unless otherwise noted.)
±15kV ESD-Protected USB Transceivers
MAX3450E/MAX3451E/MAX3452E
Pin Description
PIN
TSSOP
THIN
QFN-EP
NAME
1
15
VL
2
1
SPD
Speed-Selector Input. Connect SPD to GND to select the low-speed data rate (1.5Mbps).
Connect SPD to VL to select the full-speed data rate (12Mbps).
3
2
RCV
Differential-Receiver Output. RCV responds to the differential input on D+ and D- (Tables 3 and
4). RCV asserts low if SUS = VL.
4
3
VP
Receiver Output/Driver Input. VP functions as a receiver output when OE = VL. VP duplicates D+
when receiving. VP functions as a driver input when OE = GND.
5
4
VM
Receiver Output/Driver Input. VM functions as a receiver output when OE = VL. VM duplicates Dwhen receiving. VM functions as a driver input when OE = GND.
6
5, 8, 16
N.C.
No Connection. Not internally connected.
7
6
GND
Ground
Digital I/O Connections Logic Supply. Connect a +1.65V to +3.6V supply to VL. Bypass VL to
GND with a 0.1µF ceramic capacitor.
8
7
SUS
Suspend Input. Drive SUS low for normal operation. Drive SUS high to put the MAX3450E/
MAX3451E/MAX3452E into suspend mode. RCV asserts low in suspend mode. VP and VM
remain active in suspend mode.
9
9
OE
Output Enable. Drive OE to GND to enable the transmitter outputs. Drive OE to VL to disable the
transmitter outputs. OE also controls the I/O direction of VP and VM (Tables 3 and 4).
10
10
D-
USB Input/Output. For OE = GND, D- functions as a USB output, with VM providing the input signal. For
OE = VL, D- functions as a USB input, with VM functioning as a single-ended receiver output. Connect a
1.5kΩ resistor from D- to VTRM for low-speed (1.5Mbps) operation (MAX3450E and MAX3452E).
11
11
D+
USB Input/Output. For OE = GND, D+ functions as a USB output, with VP providing the input signal. For
OE = VL, D+ functions as a USB input, with VP functioning as a single-ended receiver output. Connect
a 1.5kΩ resistor from D+ to VTRM for full-speed (12Mbps) operation (MAX3450E and MAX3452E).
VTRM
Internal Regulator Output. VTRM provides a regulated +3.3V output. Bypass VTRM to GND with a
1µF (min) ceramic capacitor as close to the device as possible. VTRM normally derives power
from VBUS. Alternatively, drive VTRM directly with a +3.3V ±10% supply (MAX3450E and MAX3451E).
VTRM provides power to internal circuitry and provides the pullup voltage for an external USB
pullup resistor (MAX3450E and MAX3452E). Do not use VTRM to power external circuitry.
12
12
N.C.
13
13
ENUM
BD
6
FUNCTION
14
14
VBUS
—
—
EP
No Connection. Not internally connected (MAX3450E).
Enumerate Function Selection Input (MAX3451E). Drive ENUM to VL to connect the internal 1.5kΩ
resistor between VTRM and D+ or D-, depending on the SPD state. Drive ENUM to GND to
disconnect the internal 1.5kΩ resistor. For SPD = VL, the 1.5kΩ pullup resistor connects to D+.
For SPD = GND, the 1.5kΩ pullup resistor connects to D-.
Bus-Detection Output (MAX3452E). The push-pull BD output asserts low and the device enters
sharing mode if VBUS < +3.6V. BD asserts high if VBUS > +4.0V.
USB Power-Supply Input. Connect a +4.0V to +5.5V power supply to VBUS. VBUS provides power
to the internal linear regulator. Bypass VBUS to GND with a 0.1µF ceramic capacitor as close to
the device as possible. Connect VBUS and VTRM together when powering the MAX3450E or
MAX3451E with an external power supply (+3.3V ±10%).
Exposed Pad. Connect exposed pad to ground.
_______________________________________________________________________________________
±15kV ESD-Protected USB Transceivers
MAX3450E
MAX3451E
MAX3452E
TO INTERNAL
CIRCUITRY
BD
MAX3452E
ONLY
LDO
REGULATOR
VTH_VBUS
VBUS
VTRM
VL
SPD
VP
D+
VM
D-
OE
LEVEL
TRANSLATOR
RCV
SUS
TO INTERNAL
CIRCUITRY
MAX3451E
ONLY
VTRM
SPD
CONTROL
LOGIC
ENUM
GND
Detailed Description
The MAX3450E/MAX3451E/MAX3452E USB-compliant
transceivers convert single-ended or differential
logic-level signals to USB signals and USB signals to
single-ended or differential logic-level signals. The
devices fully comply with USB 1.1, as well as USB 2.0
at full- (12Mbps) and low-speed (1.5Mbps) operation.
The MAX3450E/MAX3451E/MAX3452E operate with VL
as low as +1.65V, ensuring compatibility with low-voltage ASICs.
The MAX3450E/MAX3451E/MAX3452E derive power from
the USB host (VBUS) or from a single-cell Li+ battery
(MAX3450E and MAX3451E) connected to VBUS or from
a +3.3V regulated supply connected to VBUS and VTRM.
The MAX3450E/MAX3451E/MAX3452E meet the
physical-layer specifications for logic-level supply volt-
_______________________________________________________________________________________
7
MAX3450E/MAX3451E/MAX3452E
Functional Diagram
MAX3450E/MAX3451E/MAX3452E
±15kV ESD-Protected USB Transceivers
ages (VL) from +1.65V to +3.6V. Integrated ±15kV ESD
protection protects the D+ and D- USB I/O ports.
The MAX3451E features an enumerate function providing an internal 1.5kΩ pullup resistor to VTRM. The enumerate function disconnects the 1.5kΩ pullup resistor,
allowing the MAX3451E to simulate a bus disconnect
while powered and connected to the USB cable. The
MAX3450E is pin-for-pin compatible with Micrel’s
MIC2550A. The MAX3452E features a BD output that
asserts high if VBUS is greater than +4.0V. BD asserts
low if V BUS is less than +3.6V. The MAX3450E and
MAX3452E require external pullup resistors from either
D+ or D- to VTRM to set the bus speed.
Applications Information
Power-Supply Configurations
Normal Operating Mode
Connect V L and V BUS to system power supplies
(Table 1). Connect VL to a +1.65V to +3.6V supply.
Connect VBUS to a +4.0V to +5.5V supply. Alternatively,
the MAX3450E and MAX3451E can derive power from
a single Li+ battery. Connect the battery to VBUS. VTRM
remains above +3.0V for VBUS as low as +3.1V.
Additionally, the MAX3450E and MAX3451E can derive
power from a +3.3V ±10% voltage regulator. Connect
VBUS and VTRM to an external +3.3V voltage regulator.
VBUS no longer consumes current to power the internal
linear regulator in this configuration.
Disable Mode
Connect VBUS to a system power supply and leave VL
unconnected or connect to GND. D+ and D- enter a tristate mode and VBUS (or VBUS and VTRM) consumes
less than 20µA of supply current. D+ and D- withstand
external signals up to +5.5V in disable mode (Table 2).
Sharing Mode
Connect VL to a system power supply and leave VBUS
(or VBUS and VTRM) unconnected or connect to GND.
D+ and D- enter a tri-state mode, allowing other circuitry
to share the USB D+ and D- lines, and VL consumes less
than 20µA of supply current. D+ and D- withstand
external signals up to +5.5V in sharing mode (Table 2).
Table 1. Power-Supply Configurations
VBUS (V)
VTRM (V)
VL (V)
CONFIGURATION
+4.0 to +5.5
+3.0 to +3.6 output
+1.65 to +3.6
Normal mode
NOTES
—
+3.1 to +4.5
+3.0 to +3.6 output
+1.65 to +3.6
Battery supply
MAX3450E, MAX3451E
MAX3450E, MAX3451E
+3.0 to +3.6
+3.0 to +3.6 input
+1.65 to +3.6
Voltage regulator supply
GND or floating
Output
+1.65 to +3.6
Sharing mode
Table 2
+3.0 to +5.5
VBUS
GND or floating
Disable mode
Table 2
Table 2. Disable-Mode and Sharing-Mode Connections
INPUTS/OUTPUTS
DISABLE MODE
VBUS/VTRM
• +5V input/+3.3V output
• +3.3V input/+3.3V input (MAX3450E and MAX3451E)
• +3.7V input/+3.3V output (MAX3450E and MAX3451E)
• Floating or connected to GND (MAX3450E
and MAX3451)
• < +3.6V (MAX3452E)
Floating or connected to GND
+1.65V to +3.6V input
VL
D+ and D-
High impedance
SHARING MODE
High impedance
High impedance for OE = low
VP and VM
Invalid*
RCV
Invalid*
Undefined**
High impedance
High impedance
Invalid*
Low
SPD, SUS, OE, ENUM
(MAX3451E)
BD (MAX3452E)
High for OE = high
*High impedance or low
**High or low
8
_______________________________________________________________________________________
±15kV ESD-Protected USB Transceivers
OE
OE controls the direction of communication. Drive OE
low to transfer data from the logic side to the USB side.
For OE = low, VP and VM serve as differential driver
inputs to the USB transmitter.
Drive OE high to transfer data from the USB side to the
logic side. For OE = high, VP and VM serve as singleended receiver outputs from the USB inputs
(D+ and D-). RCV serves as a differential receiver output, regardless of the state of OE.
ENUM (MAX3451E)
The MAX3451E features an enumerate function that
allows software control of USB enumeration. USB protocol requires a 1.5kΩ pullup resistor to D+ or D- to indicate the transmission speed to the host (see the SPD
section). The MAX3451E provides an internal 1.5kΩ
pullup resistor. Remove the pullup resistor from the circuit to simulate a device disconnect from the USB. Drive
ENUM low to disconnect the internal pullup resistor.
Drive ENUM high to connect the internal pullup resistor.
The SPD state determines whether the pullup resistor
connects to D+ or D-. For ENUM = high, the internal
1.5kΩ pullup resistor connects to D+ when SPD = VL
(full speed) or to D- when SPD = GND (low speed).
SPD
SPD sets the transceiver speed. Connect SPD to GND to
select the low-speed data rate (1.5Mbps). Connect SPD
to VL to select the full-speed data rate (12Mbps). The
MAX3451E provides an internal pullup resistor for
selecting the bus speed. The MAX3450E and
MAX3452E require an external pullup resistor to D+ or
D- to set the bus speed. Connect the 1.5kΩ resistor
between D+ and VTRM to set the full-speed (12Mbps)
data rate, or connect the 1.5kΩ resistor between D- and
VTRM to set the low-speed (1.5 Mbps) data rate.
tFR, tLR
tFF, tLF
VOHD
90%
10%
90%
SUS
The SUS state determines whether the MAX3450E/
MAX3451E/MAX3452E operate in normal mode or in
suspend mode. Connect SUS to GND to enable normal
operation. Drive SUS high to enable suspend mode.
RCV asserts low and VP and VM remain active in suspend mode (Tables 3 and 4). Supply current decreases
in suspend mode (see the Electrical Characteristics).
Table 3a. Transmit Truth Table
(OE = 0, SUS = 0)
INPUTS
OUTPUTS
OUTPUT STATE
VP
VM
D+
D-
RCV
0
0
0
0
X
SE0
0
1
0
1
0
Logic 0
1
0
1
0
1
Logic 1
1
1
1
1
X
Undefined
X = Undefined.
Table 3b. Transmit Truth Table
(OE = 0, SUS = 1)
INPUTS
OUTPUTS
OUTPUT STATE
VP
VM
D+
D-
RCV
0
0
0
0
0
SE0
0
1
0
1
0
Logic 0
1
0
1
0
0
Logic 1
1
1
1
1
0
Undefined
Table 4a. Receive Truth Table
(OE = 1 and SUS = 0)
INPUTS
OUTPUTS
OUTPUT STATE
D+
D-
VP
VM
RCV
0
0
0
0
X
SE0
0
1
0
1
0
Logic 0
1
0
1
0
1
Logic 1
1
1
1
1
X
Undefined
X = Undefined.
10%
VOLD
Figure 1. Rise and Fall Times
_______________________________________________________________________________________
9
MAX3450E/MAX3451E/MAX3452E
Device Control
MAX3450E/MAX3451E/MAX3452E
±15kV ESD-Protected USB Transceivers
Table 4b. Receive Truth Table
(OE = 1 and SUS = 1)
INPUTS
OUTPUTS
VP AND VM RISE/FALL TIMES < 4ns
VM
OUTPUT STATE
D+
D-
VP
VM
RCV
0
0
0
0
0
SE0
0
1
0
1
0
Logic 0
1
0
1
0
0
Logic 1
1
1
1
1
0
Undefined
VP
tPLH_DRV
tPHL_DRV
D-
BD (MAX3452E)
The push-pull bus detect (BD) output monitors VBUS
and asserts high if V BUS is greater than +4.0V. BD
asserts low if V BUS is less than +3.6V and the
MAX3452E enters sharing mode (Table 2).
VTRM
An internal linear regulator generates the VTRM voltage
(+3.3V typ). VTRM derives power from VBUS (see the
Power-Supply Configurations section). VTRM powers the
internal portions of the USB circuitry and provides the
pullup voltage for an external USB pullup resistor
MAX3450E/MAX3452E. Bypass VTRM to GND with a 1µF
ceramic capacitor as close to the device as possible.
Do not use VTRM to provide power to external circuitry.
D+ and DD+ and D- serve as bidirectional bus connections and
are ESD protected to ±15kV (Human Body Model). For
OE = low, D+ and D- serve as transmitter outputs. For
OE = high, D+ and D- serve as receiver inputs.
VBUS
For most applications, VBUS connects to the VBUS terminal on the USB connector. VBUS can also connect to
an external supply as low as +3.1V (MAX3450E and
MAX3451E). See the Power-Supply Configurations section. Drive VBUS low to enable sharing mode. Bypass
VBUS to GND with a 0.1µF ceramic capacitor as close
to the device as possible.
External Components
External Resistors
Proper USB operation requires two external resistors,
each 24.3Ω ±1%, 1/8W (or greater). Install one resistor
in series between D+ of the MAX3450E/MAX3451E/
MAX3452E and D+ on the USB connector. Install the
other resistor in series between D- of the MAX3450E/
MAX3451E/MAX3452E and D- on the USB connector
(see the Typical Operating Circuit).
10
VCRS_F , VCRS_L
D+
Figure 2. Timing of VP and VM to D+ and D-
The MAX3450E/MAX3452E requires an external 1.5kΩ
pullup resistor between VTRM and D+ or D- to set the
bus speed.
External Capacitors
The MAX3450E/MAX3451E/MAX3452E require three
external capacitors for proper operation. Bypass VL to
GND with a 0.1µF ceramic capacitor. Bypass VBUS to
GND with a 0.1µF ceramic capacitor. Bypass VTRM to
GND with a 1µF (min) ceramic capacitor. Install all capacitors as close to the device as possible.
Data Transfer
Transmitting Data to the USB
The MAX3450E/MAX3451E/MAX3452E transmit data to
the USB differentially on D+ and D-. VP and VM serve as
differential input signals to the driver (Tables 3a and 3b).
Receiving Data from the USB
To receive data from the USB, drive OE high and SUS
low. Differential data received by D+ and D- appears
as a differential logic signal at RCV. Single-ended
receivers on D+ and D- drive VP and VM, respectively
(Tables 4a and 4b).
______________________________________________________________________________________
±15kV ESD-Protected USB Transceivers
560Ω
150Ω
VL
+3V
DUT
DUT
VP/VM
D+/D-
VP/VM
D+/D560Ω
150Ω
OE
OE
VP/VM CONNECTED TO GND,
D+/D- CONNECTED TO PULLUP
D+/D- CONNECTED TO GND,
VP/VM CONNECTED TO PULLUP
D+/DVP/VM
tPLZ_DRV
tPZL_DRV
tPLZ_SE
VP/VM CONNECTED TO VL,
D+/D- CONNECTED TO PULLDOWN
OE
tPZL_SE
D+/D- CONNECTED TO +3V,
VP/VM CONNECTED TO PULLDOWN
OE
VP/VM
D+/D-
tPHZ_DRV
tPZH_DRV
tPHZ_SE
tPZH_SE
Figure 5. Enable and Disable Timing, Receiver
Figure 3. Enable and Disable Timing, Driver
INPUT RISE/FALL TIME < 4ns
+3V
MAX3450E
MAX3451E
MAX3452E
D+ / D0
TEST
POINT
RCV, VM,
AND VP
CL
(a) LOAD FOR RCV, VM, AND VP
MAX3450E
MAX3451E
MAX3452E
VL
tPLH_RCV,
tPLH_SE
24Ω
TEST
POINT
D+ AND DCL
RCV, VM, AND VP
tPHL_RCV,
tPHL_SE
Figure 4. Timing of D+ and D- to RCV, VM, and VP
15kΩ
(b) LOAD FOR D+/D-
Figure 6. Test Circuits
______________________________________________________________________________________
11
MAX3450E/MAX3451E/MAX3452E
VL
+3V
MAX3450E/MAX3451E/MAX3452E
±15kV ESD-Protected USB Transceivers
ESD Protection
D+ and D- possess extra protection against static electricity to protect the devices up to ±15kV. The ESD
structures withstand high ESD in all operating modes:
normal operation, suspend mode, and powered down.
D+ and D- provide protection to the following limits:
• ±15kV using the Human Body Model
• ±8kV using the Contact Discharge method specified
in IEC 1000-4-2
RC
1MΩ
CHARGE-CURRENTLIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
100pF
RD
1.5kΩ
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.
Figure 7. Human Body ESD Test Models
Human Body Model
Figure 7 shows the Human Body Model and Figure 8
shows the current waveform generated when discharged into a low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which then discharges into the test device through a
1.5kΩ resistor.
IP 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPERES
36.8%
IEC 1000-4-2
The IEC 1000-4-2 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 1000-4-2 is a higher peak current in IEC 1000-4-2,
due to lower series resistance. Hence, the ESD withstand voltage measured to IEC 1000-4-2 generally is
lower than that measured using the Human Body
Model. Figure 9 shows the IEC 1000-4-2 model. The
Contact Discharge method connects the probe to the
device before the probe is charged.
10%
0
0
TIME
tDL
CURRENT WAVEFORM
Figure 8. Human Body Model Current Waveform
RC
50Ω to 100Ω
CHARGE-CURRENTLIMIT RESISTOR
Machine Model
The Machine Model for ESD tests all connections using
a 200pF storage capacitor and zero discharge resistance. Its objective is to emulate the stress caused by
contact that occurs with handling and assembly during
manufacturing. All pins require this protection during
manufacturing, not just inputs and outputs. After PC
board assembly, the Machine Model is less relevant to
I/O ports.
tRL
HIGHVOLTAGE
DC
SOURCE
Cs
150pF
RD
330Ω
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Figure 9. IEC 1000-4-2 ESD Test Model
12
______________________________________________________________________________________
DEVICE
UNDER
TEST
±15kV ESD-Protected USB Transceivers
+1.65V TO +3.6V
0.1μF
0.1μF
VL
VL(I/O)
VP
VBUS
PC
USB
POWER
D-
24.3Ω 1%
D24.3Ω 1%
VM
ASIC
RCV
MAX3451E
D+
D+
GND
GND
ENUM
SUS
15kΩ
15kΩ
VTRM
1μF
SPD
OE
Chip Information
PROCESS: BiCMOS
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
PACKAGE TYPE
PACKAGE CODE
DOCUMENT NO.
14 TSSOP
U14-1
21-0066
16 Thin QFN-EP
T1633-4
21-0136
______________________________________________________________________________________
13
MAX3450/MAX3451E/MAX3452E
Typical Operating Circuit
MAX3450/MAX3451E/MAX3452E
±15kV ESD-Protected USB Transceivers
Revision History
REVISION
NUMBER
REVISION
DATE
DESCRIPTION
PAGES
CHANGED
0
4/03
Initial release
⎯
1
11/03
Changed specs
⎯
2
10/08
Added lead-free packaging. Updated Absolute Maximum Ratings information
of package thermal resistances. Updated EC table notation.
1–4, 6
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.
14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2009 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
工商网监
湘ICP备2023018690号
