MAXIM MAX4850, MAX4850H, MAX4852, MAX4852H Technical data

General Description

The MAX4850/MAX4850H/MAX4852/MAX4852H family
of dual SPDT (single-pole/double-throw) switches oper­ate from a single +2V to +5.5V supply and can handle
signals greater than the supply rail. These switches fea­ture low 3.5Ω or 3.5Ω/7Ω on-resistance with low on­capacitance, making them ideal for switching audio
and data signals.

The MAX4850/MAX4850H are configured with two
SPDT switches and feature two comparators for head­phone detection or mute/send key functions. The
MAX4852 has two SPDT switches with no comparators
for low 1µA supply current.

For over-rail applications, these devices offer either the
pass-through or high-impedance option. For the
MAX4850/MAX4852, the signal (up to 5.5V) passes
through the switch without distortion even when the posi­tive supply rail is exceeded. For the MAX4850H/
MAX4852H, the switch input becomes high impedance
when the input signal exceeds the supply rail.

The MAX4850/MAX4850H/MAX4852/MAX4852H are
available in the space-saving (3mm x 3mm), 16-pin
TQFN package and operate over the extended temper­ature range of -40°C to +85°C.

Applications

USB Switching

Audio-Signal Routing

Cellular Phones

Notebook Computers

PDAs and Other Handheld Devices

Features

♦ USB 2.0 Full Speed (12MB) and USB 1.1 Signal

Switching Compliant

♦ Switch Signals Greater than V

CC

♦ 0.1ns Differential Skew

♦ 3.5Ω/7Ω On-Resistance

♦ 135MHz -3dB Bandwidth

♦ +2V to +5.5V Supply Range

♦ 1.8V Logic Compatible

♦ Low Supply Current

1µA (MAX4852)
5µA (MAX4850)
10µA (MAX4850H/MAX4852H)

♦ Available in a Space-Saving (3mm x 3mm),

16-Pin TQFN Package

MAX4850/MAX4850H/MAX4852/MAX4852H

Dual SPDT Analog Switches with

Over-Rail Signal Handling

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

V

CC

3

MAX4850

MAX4850H

NC1

NO1

NC2

NO2

COUT2

COM1

IN1

IN2

COM2

CIN2

V

CC

3

COUT1

CIN1

MAX4852

MAX4852H

NC1

NO1

NC2

NO2

COM1

IN1

IN2

COM2

MAX4850_
MAX4852_

IN_ NO_ NC_

0 OFF ON

1 ON OFF

SWITCHES SHOWN FOR
LOGIC 0 INPUT

3.5Ω

3.5Ω

7Ω

3.5Ω

3.5Ω

7Ω

Block Diagrams/Truth Table

19-3375; Rev 0; 7/04

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.

*EP = Exposed paddle.

Pin Configurations and Selector Guide appear at end of
data sheet.

ABRIDGED DATA SHEET

PART TEMP RANGE PIN-PACKAGE

MAX4850ETE -40°C to +85°C 16 TQFN-EP* ABU

MAX4850HETE -40°C to +85°C 16 TQFN-EP* ABV

MAX4852ETE -40°C to +85°C 16 TQFN-EP* ABZ

MAX4852HETE -40°C to +85°C 16 TQFN-EP* ACA

TOP

MARK

Detailed Description

The MAX4850/MAX4850H/MAX4852/MAX4852H are low
on-resistance, low-voltage, analog switches that operate
from a +2V to +5.5V single supply and are fully specified
for nominal 3.0V applications. These devices feature
over-rail signal capability that allows signals up to 5.5V
with supply voltages down to 2.0V. These devices are
configured as dual SPDT switches.

These switches have low 50pF on-channel capacitance,
which allows for 12Mbps switching of the data signals for
USB 2.0 full speed/1.1 applications. The MAX485_ _ are
designed to switch D+ and D- USB signals with a guaran­teed skew of less than 1ns (see Figure 1), as measured
from 50% of the input signal to 50% of the output signal.

The MAX4850_ feature a comparator that can be used
for headphone or mute detection. The comparator
threshold is internally generated to be approximately 1/3
of VCC.

Applications Information

Digital Control Inputs

The logic inputs (IN_) accept up to +5.5V even if the
supply voltages are below this level. For example, with a
+3.3V VCCsupply, IN_ can be driven low to GND and
high to +5.5V, allowing for mixing of logic levels in a
system. Driving IN_ rail-to-rail minimizes power con-

sumption. For a +2V supply voltage, the logic thresholds
are 0.5V (low) and 1.4V (high); for a +5V supply voltage,
the logic thresholds are 0.8V (low) and 1.8V (high).

Analog Signal Levels

The on-resistance of these switches changes very little
for analog input signals across the entire supply volt­age range (see Typical Operating Characteristics). The
switches are bidirectional, so NO_, NC_, and COM_
can be either inputs or outputs.

Comparator

The positive terminal of the comparator is internally set to
V

CC

/3. When the negative terminal (CIN_) is below the
threshold (VCC/3), the comparator output (COUT_) goes
high. When CIN_ rises above VCC/3, COUT_ goes low.

The comparator threshold allows for detection of head­phones since headphone audio signals are typically
biased to VCC/2.

Power-Supply Sequencing

Caution: Do not exceed the absolute maximum ratings
because stresses beyond the listed ratings may cause
permanent damage to the device.

Proper power-supply sequencing is recommended for
all CMOS devices. Always apply VCCbefore applying
analog signals, especially if the analog signal is not
current-limited.

MAX4850/MAX4850H/MAX4852/MAX4852H

Dual SPDT Analog Switches with

Over-Rail Signal Handling

______________________________________________________________________________________ 11

ABRIDGED DATA SHEET

MAX4850/MAX4850H/MAX4852/MAX4852H

Dual SPDT Analog Switches with
Over-Rail Signal Handling

12 ______________________________________________________________________________________

Test Circuits/Timing Diagrams

Figure 1. Switching Time

Figure 2. Input/Output Skew Timing Diagram

ABRIDGED DATA SHEET

MAX4850_
MAX4852_

V

NO

LOGIC
INPUT

TxD+

V

CC

V

CC

NO_

IN_

GND

C

INCLUDES FIXTURE AND STRAY CAPACITANCE.

L

R

= V

V

OUT

NO (

RL + R

COM_

R

L

)

ON

A

R

s

tR < 20ns

V

CC

LOGIC
INPUT

INPUT

0V

V

OUT

0V

IN DEPENDS ON SWITCH CONFIGURATION;
INPUT POLARITY DETERMINED BY SENSE OF SWITCH.

10%

90%

V

OUT

INPUT A

INPUT A-

SWITCH
OUTPUT

SWITCH

L

C

L

B

C

L

50%

0.9 x V

t

ON

V

+ 0.5V

CC

HIGH-Z MODE

t

HIZ

NORMAL MODE NORMAL MODE

t

ri

90%

50%

t

skew_i

50%

10%

t

fi

tF < 20ns

t

OFF

0.9 x V

0UT

t

OUT

HIZB

TxD-

|t

|

ro - tri

|t

|

fo - tfi

|t

|

skew_o

|t

|

skew_i

Rs = 39Ω

= 50pF

C

L

DELAY DUE TO SWITCH FOR RISING INPUT AND RISING OUTPUT SIGNALS.

DELAY DUE TO SWITCH FOR FALLING INPUT AND FALLING OUTPUT SIGNALS.

CHANGE IN SKEW THROUGH THE SWITCH FOR OUTPUT SIGNALS.

CHANGE IN SKEW THROUGH THE SWITCH FOR INPUT SIGNALS.

A-

R

s

B-

C

L

OUTPUT B

OUTPUT B-

10%

90%

t

ro

50%

t

fo

50%

90%

t

skew_o

10%