MAX4704 Maxim, MAX4704 Datasheet - Page 7

• Manufacturer Part Number: MAX4704
• Description: The MAX4704 low-voltage, 4-channel analog multiplexer operates from a single +1
• Manufacturer: Maxim

The MAX4704 low-voltage, 4-channel analog multiplexer
operates from a single +1.8V to +5.5V supply. When
powered from a +2.7V supply, the device has a 60Ω
(max) on-resistance (R
and 5Ω (max) R
+1.8V-logic compatible from a +2.7V to +3.3V supply.
The MAX4704 logic inputs are +1.8V CMOS logic compati-
ble for 3V operation and TTL compatible for 5V operation of
V+. Driving ADD_ rail-to-rail minimizes power consumption.
Analog signals that range over the entire supply volt-
age (V+ to GND) are passed with very little change in
on-resistance (see Typical Operating Characteristics ).
The switches are bidirectional, so the NO_ and COM
pins can be either inputs or outputs.
Caution: Do not exceed the absolute maximum rat-
ings because stresses beyond those listed may
cause permanent damage to devices.
Proper power-supply sequencing is recommended for all
CMOS devices. Always apply V+ before applying analog
signals, especially if the analog signal is not current limited.
If this sequencing is not possible, and if the analog inputs
are not current limited to <20mA, add a small-signal diode
µMAX
10
—
—
1
2
3
4
5
6
7
8
9
PIN
QFN-EP
Applications Information
ON
Power-Supply Sequencing and
2, 8
10
11
12
—
1
3
4
5
6
7
9
_______________________________________________________________________________________
flatness. The digital logic inputs are
ON
Detailed Description
), with 3Ω (max) R
Overvoltage Protection
NAME
ADDB
ADDA
Digital Control Inputs
COM
GND
NO2
NO3
NO1
NO0
Analog Signal Levels
N.C.
INH
V+
EP
Positive Supply Voltage
No Connection. Not internally connected.
Analog Switch 2. Normally open.
Analog Switch 3. Normally open.
Analog Switch 1. Normally open.
Inhibit. Connect to GND for normal operation. Connect to logic-level high to turn all
switches off.
Ground
Address Decoder Selection B
Address Decoder Selection A
Analog Switch 0. Normally open.
Analog Switch Common Terminal
Exposed Pad. Internally connected to GND. Connect to a large ground plane to maximize
thermal performance; not intended as an electrical connection point (QFN package only).
ON
4:1 Analog Multiplexer in QFN
matching
(D1) as shown in Figure 1. If the analog signal can dip
below GND, add D2. Adding protection diodes reduces
the analog range to a diode drop (about 0.7V) below V+
(for D1), and a diode drop above ground (for D2).
On-resistance increases slightly at low supply voltages.
Maximum supply voltage (V+) must not exceed +6V.
Adding protection diode D2 causes the logic threshold
to be shifted relative to GND. TTL compatibility is not
guaranteed when D2 is added.
Protection diodes D1 and D2 also protect against some
overvoltage situations. In the circuit in Figure 1, if the
supply voltage is below the absolute maximum rating,
and if a fault voltage up to the absolute maximum rating
is applied to an analog signal pin, no damage will result.
Figure 1. Overvoltage Protection Using Two External Blocking
Diodes
V g
Low-Voltage, 60 Ω ,
FUNCTION
NO
POSITIVE SUPPLY
GND
V+
D1
D2
Pin Description
COM
MAX4704
7