MAXIM MAX4999 User Manual
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General Description
The MAX4999 differential Hi-Speed USB analog multiplexer features low on-capacitance (C
ON
) switching,
making it an ideal solution for the USB server/mass
storage market. The MAX4999 is designed for USB 2.0
low-/full-/Hi-Speed applications with capability of supporting data rates up to 480Mbps.
The MAX4999 is a differential 8:1 multiplexer. The
MAX4999 features three digital inputs to control the signal path. Typical applications include switching a USB
connector between eight USB hosts and a USB device.
An enable input (EN) is provided to disable all channels
and place the device into a high-impedance state
(standby mode), shutting off the charge pump for minimum power consumption.
The MAX4999 operates from a +3.0V to +3.6V powersupply voltage and is specified over the -40°C to +85°C
extended temperature range. The MAX4999 is available
in a 5mm x 5mm, 32-pin TQFN package.
Applications
Keyboard, Video, Mouse (KVM)
Servers/RAID
Mass Storage
Workstations
Features
♦ Single +3.0V to +3.6V Power-Supply Voltage
♦ Low 6.5Ω (typ) On-Resistance (R
ON
)
♦ -3dB Bandwidth: 1200MHz (typ)
♦ Enable Input Puts All Channels in High-
Impedance State (Standby Mode)
♦ Low Operating Current (1µA) and Ultra-Low
Quiescent Current (30nA) in Standby Mode
♦ Low Threshold Eliminates the Need for
Translators in 1.8V Low-Voltage Systems
♦ Small 32-Pin, 5mm x 5mm, TQFN Package
MAX4999
USB 2.0 Hi-Speed Differential
8:1 Multiplexer
________________________________________________________________
Maxim Integrated Products
1
Ordering Information
19-4127; Rev 0; 5/08
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.
+
Denotes a lead-free package.
*
EP = Exposed pad.
Pin Configuration
MAX4999
TQFN
5mm x 5mm
TOP VIEW
29
30
28
27
12
11
13
V
CC
COM0
COM1
C0
C1
14
GND
D4_0
GND
V
CC
GND
D3_1
D3_0
12
D6_1
4567
2324 22 20 19 18
D6_0
GND
GND
D1_1
D1_0
GND
EN
D4_1
3
21
31
10
D7_1
D0_1
32
9
D7_0
D0_0
GND
26
15
D2_0
D5_0
25
16
D2_1
C2
GND
8
17
D5_1
*CONNECT EXPOSED PAD TO GND.
*EP
PART TEMP RANGE PIN-PACKAGE
MAX4999ETJ+ -40°C to +85°C 32 TQFN-EP*
MAX4999
USB 2.0 Hi-Speed Differential
8:1 Multiplexer
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
CC
= +3.0V to +3.6V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VCC= +3.3V and TA= +25°C.) (Note 3)
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.)
V
CC
...........................................................................-0.3V to +4V
All Other Pins (Note 1)..............................................-0.3V to +4V
Continuous Current (COM_ to any switch) .......................±60mA
Peak Current (COM_ to any switch) (pulsed at 1ms,
10% duty cycle)..........................................................±120mA
Continuous Power Dissipation (T
A
= +70°C)
32-Lead TQFN (derate 34.5mW/°C above +70°C) ....2759mW
Junction-to-Case Thermal Resistance (θ
JC
) (Note 2)
32-Lead TQFN ............................................................2.0°C/W
Junction-to-Ambient Thermal Resistance (θ
JA
) (Note 2)
32-Lead TQFN .............................................................29°C/W
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1: Signals exceeding GND are clamped by internal diodes. Limit forward-diode current to maximum current rating.
Note 2: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a
four-layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial
.
POWER SUPPLY
Supply Voltage V
Quiescent Supply Current I
ANALOG SWITCH
On-Resistance R
On-Resistance Match ΔR
On-Resistance Match Between
Channels
Leakage Current COM_, D_0, D_1 I
SWITCH AC PERFORMANCE (Note 4)
Crosstalk V
Off-Isolation V
Bandwidth -3dB BW RL = 45Ω unbalanced (Figure 3) 1200 MHz
On-Capacitance C
Off-Capacitance C
Propagation Delay t
Turn-On Time t
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
CC
O
ONICOM_
ONSCVCOM_
ΔR
ONBCVCOM_
L
DCT1
OFF
ON
OFF
PD
ON
Charge pump on 5
Charge pump off 1
= ±10mA 6.5 12 Ω
= 1V, TA = +25°C 0.8 Ω
= 1V, TA = +25°C 1 Ω
VCC = +3.6V -1 +1 µA
Any switch to non-paired switch at 500MHz
(Figure 3)
Any switch to non-paired switch at 240MHz
(Figure 3)
f = 1MHz 6
Taken from S11 parameters at f = 240MHz 3.0
f = 1MHz, COM_ 5
Taken from S11 parameters at f = 240MHz 3.0
RL = RS = 50Ω (Figure 2) 300 ps
VD0 or VD1 = +1.5V, RL = 300Ω, CL = 35pF,
= VCC, VIL = 0V (Figure 1)
V
IH
3.0 3.6 V
-30 dB
-27 dB
10 µs
µA
pF
pF
MAX4999
USB 2.0 Hi-Speed Differential
8:1 Multiplexer
_______________________________________________________________________________________ 3
Note 3: All units are 100% production tested at TA= +85°C. Limits over the operating temperature range are guaranteed by design
and not production tested.
Note 4: Guaranteed by design.
ELECTRICAL CHARACTERISTICS
(V
CC
= +3.0V to +3.6V, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VCC= +3.3V and TA= +25°C.) (Note 3)
Test Circuits/Timing Diagrams
Figure 1. Switching Time
Turn-Off Time t
Output Skew Same Port t
SWITCH LOGIC
Input Logic Low V
Input Logic High V
Input Logic Hysteresis V
Input Leakage Current I
ESD PROTECTION
All Pins Human Body Model ±2 kV
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
OFF
PD
IL
IH
HYST
LEAK
VD0 or VD1 = +1.5V, RL = 300Ω, CL = 35pF,
= VCC, VIL = 0V (Figure 1)
V
IH
Skew between any D_0, D_1 line, same port
45Ω unbalanced I/O, f = 240MHz (Figure 2)
VCC = +3.0V 0.6 V
VCC = +3.6V 1.7 V
VCC = +3.6V, V
COM_
= 0V or V
CC
-1 +1 µA
10 µs
30 ps
200 mV
MAX4999
V
N_
LOGIC
INPUT
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
V
RL + R
D0_
OR D1_
C_
OUT
= V
GND
N_ (
R
V
CC
V
LOGIC
COM_
R
L
L
)
ON
V
OUT
C
L
INPUT
SWITCH
OUTPUT
IH
V
IL
0V
50%
V
OUT
0.9 x V
0UT
t
ON
IN DEPENDS ON SWITCH CONFIGURATION;
INPUT POLARITY DETERMINED BY SENSE OF SWITCH.
tR < 5ns
tF < 5ns
t
OFF
0.9 x V
OUT
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