SmartSwitch
TM
General Description
The AAT4296/98 SmartSwitch is a member of
AnalogicTech's Application Specific Power MOS-
FETTM (ASPMTM) product family. The AAT4296/98
is comprised of five/six push/pull output switches
that gate each respective output between a common
input supply and ground. This device is targeted for
I/O expansion applications, but can also be used for
a combination of general purposes to simplify power
switching with an off state load discharge.
The AAT4296/98 operates over an input voltage
range of 1.8V to 5.5V, making it ideal for battery-
powered applications. The state of each output
channel is controlled with a single GPIO via the
EN/SET pin using AnalogicTech's Simple Serial
ControlTM (S
2
CwireTM) interface. When EN/SET is
pulled to logic high, the device is enabled and con-
sumes 3A of typical quiescent current. In the off
state, each output is pulled low to ground to affect
a logic low state for I/O expander or power switch-
ing applications; this circuit will act as a load dis-
charge function to rapidly turn off a load circuit.
The AAT4296 is offered in a Pb-free 8-pin SC70JW
package, and the AAT4298 is offered in a Pb-free
12-pin TSOPJW package. Both devices are rated
over the -40C to +85C temperature range.
Features
V
IN
Range: 1.8V to 5.5V
Independent Push/Pull Channels
-- AAT4296: Five Channels
-- AAT4298: Six Channels
User-Programmable Interface
Single GPIO Controls State of Each Output
Optional Fast Auto-Discharge
Low Quiescent Current: 3A Typical
Temperature Range: -40C to +85C
Available in Pb-Free 8-Pin SC70JW
(AAT4296) and 12-Pin TSOPJW
(AAT4298) Packages
Applications
Cell Phones
Multiple Low Power Switching
Personal Communication Devices
Portable Electronic Devices
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
Typical Application
AAT4298
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
GND
OUT 1
OUT 2
OUT 3
OUT 4
OUT 5
OUT 6
EN/SET
EN/SET Input
VCC Input
VCC
4296.2005.10.1.0
1
Pin Descriptions
Pin Configuration
AAT4296
AAT4298
SC70JW-8
TSOPJW-12
(Top View)
(Top View)
1
2
3
4
5
6
12
11
10
9
8
7
N/C
GND
OUT5
OUT4
OUT3
N/C
N/C
EN/SET
OUT1
OUT2
VCC
OUT6
OUT2
OUT1
EN/SET
OUT3
OUT4
OUT5
GND
VCC
1
2
3
4
5
6
7
8
Pin #
AAT4296
AAT4298
Symbol
Function
1
8
VCC
Input supply voltage.
2
9
OUT2
Channel 2 output pin.
3
10
OUT1
Channel 1 output pin.
4
11
EN/SET
Input control pin using S
2
Cwire serial interface. The device records rising edges
of the clock and decodes them into 32 (AAT4296) or 64 (AAT4298) states con-
trolling the ON/OFF states of the outputs. See Table 1 for output settings. In
addition, a logic low forces the device into shutdown mode, reducing the supply
current to less than 1A. This pin should not be left floating.
5
2
GND
Ground.
6
3
OUT5
Channel 5 output pin.
7
4
OUT4
Channel 4 output pin.
8
5
OUT3
Channel 3 output pin.
N/A
7
OUT6
Channel 6 output pin.
N/A
1, 6, 12
N/C
Not connected.
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
2
4296.2005.10.1.0
Absolute Maximum Ratings
1
Thermal Information
Symbol
Description
Value
Units
JA
Thermal Resistance
2
SC70JW-8
225
C/W
TSOPJW-12
160
P
D
Maximum Power Dissipation
3
SC70JW-8
440
mW
TSOPJW-12
625
Symbol
Description
Value
Units
V
CC
to GND
Input to GND
-0.3 to 6.0
V
OUTx to GND
Output (Source) to GND
-0.3 to V
IN
+ 0.3
V
EN/SET
EN/SET to GND
-0.3 to 6.0
V
T
J
Operating Junction Temperature Range
-40 to +150
C
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
3
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi-
tions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
2. Mounted on an FR4 board.
3. Derate 4.4mW/C above 25C.
Electrical Characteristics
1
V
CC
= 5.0V; T
A
= -40C to +85C, unless otherwise noted. Typical values are T
A
= 25C.
Symbol
Description
Conditions
Min
Typ
Max Units
V
CC
Supply Voltage Range
1.8
5.5
V
I
Q
Quiescent Current
EN/SET = V
CC
= 5V, I
OUT
= 0,
3.0
10
A
All Switches ON
EN/SET = GND, V
CC
= 5V,
1.0
OUTx = Open
On Resistance P-Channel
V
CC
= 5V
2.5
6.0
R
DS(ON)
V
CC
= 3.6V
3.0
7.0
On Resistance N-Channel
V
CC
= 5V
1.9
6.0
V
CC
= 3.6V
2.0
7.0
T
CRDS
On Resistance
2800
ppm/C
Temperature Coefficient
T
ON
Output Turn-On Time
2
V
CC
= 5V, C
OUT
= 100nF; T
A
= 25C
1.6
2.7
s
T
OFF
Output Turn-Off Time
3
V
CC
= 5V, C
OUT
= 100nF; T
A
= 25C
0.8
2.1
s
EN/SET
V
EN(L)
Enable Threshold Low
V
IN
= 1.8V
0.4
V
V
EN(H)
Enable Threshold High
V
IN
= 5.5V
1.4
V
T
EN/SET LO
EN/SET Low Time
0.3
75
s
T
EN/SET_HI_MIN
Minimum EN/SET High Time
50
ns
T
EN/SET_HI_MAX
Maximum EN/SET High Time
75
s
T
OFF
EN/SET Off Timeout
500
s
T
LAT
EN/SET Latch Timeout
500
s
I
EN/SET
EN/SET Input Leakage
-1
1
A
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4
4296.2005.10.1.0
1. The AAT4296/98 is guaranteed to meet performance specifications over the -40C to +85C operating temperature range and is
assured by design, characterization, and correlation with statistical process controls.
2. T
ON
is the time after latch timeout to 90% of the output voltage. See Figure 1.
3. T
OFF
is the time after off timeout to 10% of the output voltage. See Figure 1.
Typical Characteristics
Unless otherwise noted, V
IN
= 5V, C
IN
= 1F, C
OUTx
= 0.1F, T
A
= 25C.
P-Channel R
DS(ON)
vs. Temperature
(I
LOAD
= 100mA)
Temperature (
C)
R
DS(ON)
(
)
R
DS3
R
DS1
1.7
1.9
2.1
2.3
2.5
2.7
2.9
3.1
3.3
-40
-20
0
20
40
60
80
100
R
DS6
R
DS5
R
DS4
R
DS2
P-Channel R
DS(ON)
vs. Input Voltage
(I
LOAD
= 100mA)
Input Voltage (V)
R
DS(ON)
(
)
0
5
10
15
20
25
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
R
DS1
R
DS2
R
DS6
R
DS5
R
DS4
R
DS3
V
IL
vs. Input Voltage
Input Voltage (V)
V
IL
(V)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
85
C
25
C
-40
C
V
IH
vs. Input Voltage
Input Voltage (V)
V
IH
(V)
0.6
0.7
0.8
0.9
1.0
1.1
1.2
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
85
C
25
C
-40
C
Quiescent Current vs. Temperature
Temperature (
C)
Quiescent Current (
A)
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
-40
-20
0
20
40
60
80
100
V
IN
= 5.0V
V
IN
= 3.6V
Quiescent Current vs. Input Voltage
Input Voltage (V)
Quiescent Current (
A)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
1.5
2
2.5
3
3.5
4
4.5
5
5.5
85C
25C
-40C
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
5
Typical Characteristics
Unless otherwise noted, V
IN
= 5V, C
IN
= 1F, C
OUTx
= 0.1F, T
A
= 25C.
EN/SET Off Timeout vs. Temperature
Temperature (
C)
Off Timeout, T
OFF
(
s)
50
100
150
200
250
300
350
-40
-20
0
20
40
60
80
100
V
IN
= 3.3V
V
IN
= 1.8V
V
IN
= 5.0V
EN/SET Latch Timeout vs. Temperature
Temperature (
C)
Latch Timeout, T
LAT
(s)
50
100
150
200
250
300
350
-40
-20
0
20
40
60
80
100
V
IN
= 5.0V
V
IN
= 3.3V
V
IN
= 1.8V
N-Channel R
DS(ON)
vs. Temperature
(V
IN
= 3.6V; I
LOAD
= 100mA)
Temperature (
C)
R
DS(ON)
(
)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
-40
-20
0
20
40
60
80
100
R
DS6
R
DS5
R
DS2
R
DS1
R
DS3
R
DS4
P-Channel R
DS(ON)
vs. Temperature
(V
IN
= 3.6V; I
LOAD
= 100mA)
Temperature (
C)
R
DS(ON)
(
)
2.2
2.5
2.8
3.1
3.4
3.7
4.0
-40
-20
0
20
40
60
80
100
R
DS1
R
DS4
R
DS2
R
DS5
R
DS3
R
DS6
N-Channel R
DS(ON)
vs. Temperature
(I
LOAD
= 100mA)
Temperature (
C)
R
DS(ON)
(
)
0.8
1.1
1.4
1.7
2.0
2.3
2.6
2.9
-40
-20
0
20
40
60
80
100
R
DS6
R
DS3
R
DS4
R
DS5
R
DS2
R
DS1
R
DS1
N-Channel R
DS(ON)
vs. Input Voltage
(I
LOAD
= 100mA)
Input Voltage (V)
R
DS(ON)
(
)
1.0
1.5
2.0
2.5
3.0
3.5
4.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
R
DS6
R
DS5
R
DS2
R
DS1
R
DS3
R
DS4
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
6
4296.2005.10.1.0
Typical Characteristics
Unless otherwise noted, V
IN
= 5V, C
IN
= 1F, C
OUTx
= 0.1F, T
A
= 25C.
Turn-On Characteristic
(R
LOAD1
= R
LOAD2
= 100
; C
OUT1
= C
OUT2
= 0.1
F)
Time (50
s/div)
EN/SET
(5V/div)
V
OUT1
(5V/div)
V
OUT2
(5V/div)
0V
5V
5V
0V
5V
0V
Turn-On Characteristic
(R
LOAD1
= R
LOAD2
= 100
; C
OUT1
= C
OUT2
= 0.1
F)
Time (50
s/div)
EN/SET
(5V/div)
V
OUT1
(5V/div)
V
OUT2
(5V/div)
0V
5V
5V
0V
5V
0V
Turn-On Characteristic
(R
LOAD1
= R
LOAD2
= 100
; C
OUT1
= C
OUT2
= 0.1
F)
Time (50
s/div)
EN/SET
(5V/div)
V
OUT1
(5V/div)
V
OUT2
(5V/div)
0V
5V
5V
0V
5V
0V
Turn-On Characteristic
(R
LOAD1
= R
LOAD2
= 100
; C
OUT1
= C
OUT2
= 0.1
F)
Time (50
s/div)
EN/SET
(5V/div)
V
OUT1
(5V/div)
V
OUT2
(5V/div)
0V
5V
5V
0V
5V
0V
Turn-On and Turn-Off Time
vs. Temperature
Temperature (
C)
Time (
s)
0.0
0.4
0.8
1.2
1.6
2.0
-40
-20
0
20
40
60
80
100
T
ON
(Rise Time)
T
OFF
(Fall Time)
EN/SET Timeout vs. Input Voltage
Input Voltage (V)
Timeout (
s)
80
110
140
170
200
230
260
290
1.5
2
2.5
3
3.5
4
4.5
5
5.5
T
LATCH
T
OFF
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
7
Typical Characteristics
Unless otherwise noted, V
IN
= 5V, C
IN
= 1F, C
OUTx
= 0.1F, T
A
= 25C.
Time (50s/div)
EN/SET
(5V/div)
V
OUT1
(5V/div)
V
OUT2
(100mV/div,
AC coupled)
Turn-On Transient Characteristic
(R
LOAD1
= R
LOAD2
= 100
; C
OUT1
= C
OUT2
= 0.1F)
0V
5V
5V
0V
5V
Transition of Outputs
(R
LOAD1
= R
LOAD2
= 100
; C
OUT1
= C
OUT2
= 0.1F)
Time (50s/div)
EN/SET
(5V/div)
V
OUT1
(5V/div)
V
OUT2
(5V/div)
0V
5V
5V
0V
5V
0V
Turn-Off Characteristic
(R
LOAD1
= R
LOAD2
= 100
; C
OUT1
= C
OUT2
= 0.1
F)
Time (50
s/div)
EN/SET
(5V/div)
V
OUT1
(5V/div)
V
OUT2
(5V/div)
0V
5V
5V
0V
5V
0V
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
8
4296.2005.10.1.0
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
9
Functional Description
The AAT4296/98 is comprised of five/six push/pull
output slew rate limited load switches primarily tar-
geted for microcontroller general purpose
input/output (I/O) expansion applications. Each
push/pull output is supplied by the common V
CC
input and is controlled via the digital EN/SET input
pin. When a given output is enabled, the voltage
source applied to the VCC pin is then switched to
the respective output. The high-side P-channel
MOSFET transistor has a typical on resistance
(R
DS(ON)
) of 3
when operating from a 3.6V supply.
When a respective output is disabled or turned off,
the given output pin is then connected to ground
through a low side N-channel MOSFET with a typi-
cal on resistance (R
DS(ON)
) of 2
. This circuit archi-
tecture affects a simple logic control with the high
level based on the applied V
CC
. For the AAT4296,
this creates a 1-to-5 I/O expander, and for the
AAT4298 this creates a 1-to-6 I/O expander. Both
the AAT4296 and AAT4298 have been designed to
operate with an input voltage range of 1.8V to 5.5V,
making them ideal for battery-powered applications.
Functional Block Diagram
V
CC
GND
OUT1
AAT4298
OUT2
OUT3
OUT4
OUT5
EN/SET
S
2
Cwire
Serial
Interface
OUT6
These devices may also be used for load switching
applications, as well as I/O expansion. Since the
V
CC
is gated to each output through a slew rate lim-
ited low on-resistance switch, they are ideal for
controlling applications circuits with light load cur-
rent requirements. Such applications could include
simple LED function indicator lamps, RGB LED
fashion lighting, audio and RF circuits, or any other
system with a power requirement that does not
exceed the thermal dissipation limits of the load
switch and device package.
Each device push/pull output may be represented
by the following circuit and simplified equivalent
model (Figures 1 and 2):
Figure 1: Push/Pull Output Circuit.
Figure 2: Simplified Equivalent Model.
The state of each output is controlled via the
EN/SET pin using AnalogicTech's S
2
Cwire inter-
face. To enable a respective switch, a series of
clocked pulses should be applied to the EN/SET
pin. The number of pulses clocked will determine
the switch configuration based on the truth table
shown in Table 1. At the end of the serial pulse
data set, the EN/SET set pin should be held high
to then latch the clocked data and enable the
desired switch configuration. When the device is
enabled with the EN/SET held to a logic high state,
the device quiescent current consumption will typ-
ically increase to 3A and normal ambient room
temperatures. If output sequencing of the switches
is not necessary, all of the outputs will be switched
on simultaneously on the first rising edge of the
EN/SET pin by simply pulling the EN/SET to a
logic high level. The default switch position for
one clock pulse is all switches "on." However, if
output sequencing is desired, a series of pulses on
the EN/SET pin will set the outputs to the desired
state (refer to Table 1 for output settings).
The AAT4296/98 offers two different options when
the switches are in the off state. For applications
with an active pull down or auto-discharge
requirement, the internal N-channel switch will
connect the output node to ground with a series
resistance of 2
.
S
2
Cwire Serial Interface
The ON/OFF state of the output is controlled by the
EN/SET serial data input. An internal control
counter is clocked on the rising edge of the
EN/SET pin and is decoded into the 32/64 possible
states (see Table 1).
3
2
V
CC
Control
OUT
OUT
V
CC
Control
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
10
4296.2005.10.1.0
10
4296.2005.10.1.0
Table 1: Output Settings.
AAT4298
AAT4298
AAT4296 (only)
Clock OUT6 OUT5 OUT4 OUT3 OUT2 OUT1 Clock
OUT6 OUT5 OUT4 OUT3 OUT2 OUT1
1
on
on
on
on
on
on
33
off
on
on
on
on
on
2
on
on
on
on
on
off
34
off
on
on
on
on
off
3
on
on
on
on
off
on
35
off
on
on
on
off
on
4
on
on
on
on
off
off
36
off
on
on
on
off
off
5
on
on
on
off
on
on
37
off
on
on
off
on
on
6
on
on
on
off
on
off
38
off
on
on
off
on
off
7
on
on
on
off
off
on
39
off
on
on
off
off
on
8
on
on
on
off
off
off
40
off
on
on
off
off
off
9
on
on
off
on
on
on
41
off
on
off
on
on
on
10
on
on
off
on
on
off
42
off
on
off
on
on
off
11
on
on
off
on
off
on
43
off
on
off
on
off
on
12
on
on
off
on
off
off
44
off
on
off
on
off
off
13
on
on
off
off
on
on
45
off
on
off
off
on
on
14
on
on
off
off
on
off
46
off
on
off
off
on
off
15
on
on
off
off
off
on
47
off
on
off
off
off
on
16
on
on
off
off
off
off
48
off
on
off
off
off
off
17
on
off
on
on
on
on
49
off
off
on
on
on
on
18
on
off
on
on
on
off
50
off
off
on
on
on
off
19
on
off
on
on
off
on
51
off
off
on
on
off
on
20
on
off
on
on
off
off
52
off
off
on
on
off
off
21
on
off
on
off
on
on
53
off
off
on
off
on
on
22
on
off
on
off
on
off
54
off
off
on
off
on
off
23
on
off
on
off
off
on
55
off
off
on
off
off
on
24
on
off
on
off
off
off
56
off
off
on
off
off
off
25
on
off
off
on
on
on
57
off
off
off
on
on
on
26
on
off
off
on
on
off
58
off
off
off
on
on
off
27
on
off
off
on
off
on
59
off
off
off
on
off
on
28
on
off
off
on
off
off
60
off
off
off
on
off
off
29
on
off
off
off
on
on
61
off
off
off
off
on
on
30
on
off
off
off
on
off
62
off
off
off
off
on
off
31
on
off
off
off
off
on
63
off
off
off
off
off
on
32
on
off
off
off
off
off
64
off
off
off
off
off
off
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
11
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
12
4296.2005.10.1.0
The S
2
Cwire interface relies on the number of ris-
ing edges of the EN/SET pin to address and load
the registers. S
2
Cwire latches data or address
after the EN/SET pin has been held high for time
T
LAT
. The interface records rising edges of the
EN/SET pin and decodes them into 32 (for
AAT4296) or 64 (for AAT4298) different states, as
indicated in Table 1. There are 32 (for AAT4296)/
64 (for AAT4298) different sequences for control-
ling individual turn-on/turn-off of each switch. The
counter can be clocked at speeds up to 1MHz,
such that intermediate states are not visible.
Alternatively, the EN/SET clock pulses may be
entered one at a time for desired setting. The first
rising edge of EN/SET enables the IC and turns all
the switches ON. Once the final clock cycle is
received, the EN/SET pin is held high to maintain
the device setting. The device is disabled 500s
(T
OFF
) after the EN/SET pin transitions to a logic
low state.
Figure 3: Timing Diagram.
OUTn
T
H
T
L
T
LAT
T
ON
T
O
T
OFF
EN/SET
Applications Information
The AAT4296 and AAT4298 have been designed
so that no external parts are required for the device
to function as a general purpose I/O expander.
Such external parts could include bypass capaci-
tors, or pull-up or pull-down resistors.
For applications which may use some or all of the
output to switch light load current levels to applica-
tion circuits, good engineering practice would dic-
tate the use of small bypass capacitors place on
the V
CC
input and each output which is being used
to conduct current to a load. The use of small
ceramic capacitors between the input and output
nodes to ground will aid in reducing line and load
transient response effects. Refer to the application
schematic of Figure 4 for an example for placing
bypass capacitors.
Input Capacitor
Typically a 0.1F to 1F capacitor is recommend-
ed for C
IN
in most applications. A C
IN
capacitor is
not required for basic operation; however, C
IN
is
useful in preventing load transient effects from
affecting upstream circuits when internal switches
are enabled to their respective output load circuits.
C
IN
should be located as close to the device V
IN
pin
as practically possible.
There is no specific capacitor equivalent series
resistance (ESR) requirement for C
IN
; however, for
higher current operation, ceramic capacitors are rec-
ommended for CIN due to their inherent capability
over tantalum or aluminum electrolytic capacitors to
withstand input current surges from low impedance
sources, such as batteries in portable devices.
Output Capacitor
For typical applications where the AAT4696/98 is
used for I/O expansion, no output capacitors are
required. Many other common applications such
as controlling LED indicator lamps in portable prod-
ucts do not require an output capacitor because
the end load is not sensitive to device turn-on tran-
sient effects.
For improved load transient response in systems
using the AAT4296/98 for load switching, the addi-
tion of a small output capacitor placed between the
output pins and ground can have a beneficial
effect. A 0.1F ceramic capacitor is suggested as
a reasonable value for an output capacitor. Please
refer to Figure 4.
Applications Circuit
Figure 4: Typical Application Diagram.
AAT4298
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
GND
C1*
C2*
C3*
C4*
C5*
C6*
OUT 1
OUT 2
OUT 3
OUT 4
OUT 5
OUT 6
EN/SET
EN/SET Input
VCC Input
VCC
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
13
The output capacitor has no specific capacitor type
or ESR requirement. If desired, C
OUT
may be
increased to a value greater than 0.1F without
limit to accommodate any load transient condition
without adversely affecting the device turn-on slew
rate time.
Thermal Considerations
The AAT4296 and AAT4298 are designed to deliv-
er continuous output load currents. The limiting
characteristic for maximum safe operating output
load current is package power dissipation. In order
to obtain high operating currents, careful device
layout and circuit operating conditions need to be
taken into account.
At any given ambient temperature (T
A
), the maxi-
mum package power dissipation can be deter-
mined by the following equation:
Constants for the AAT4296 and AAT4298 are max-
imum junction temperature, T
J(MAX)
= 125C, and
package thermal resistance,
JA
= 120C/W. Worst-
case conditions are calculated at the maximum
operating temperature, where T
A
= 85C. Typical
conditions are calculated under normal ambient
conditions, where T
A
= 25C.
At 25C ambient, the AAT4296 is capable of dissi-
pating 440mW of power. If all five channels have
5.0V output, the average current is 121mA per
channel. The AAT4298 is capable of dissipating
625mW of power. If all six channels have 5.0V out-
put, the average current is 131.5mA per channel.
At 85C ambient, the AAT4296 is capable of dissi-
pating 177.78mW of power. If all five channels
have 5.0V output, the average current is 76.5mA
per channel. The AAT4298 is capable of dissipat-
ing 250mW of power. If all six channels have 5.0V
output, the average current is 83mA per channel.
P
D(MAX)
=
T
J(MAX)
- T
A
JA
*Use of capacitors on each output is optional.
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
14
4296.2005.10.1.0
Figure 5: Infrared, Bluetooth, RGB, and Backlighting Control.
IN
EN/SET
OUT2
GND
OUT6
OUT5
OUT4
OUT3
OUT1
AAT4298
R
G
B
5V
A series of
pulses
Bluetooth
Device
EN
Infrared
Device
EN
Backlighting
Driving LED Loads
The AAT4296 and AAT4298 can be used to drive
LEDs or other applications with light load current
requirements. LED applications may include main
and sub-LCD display backlighting, camera photo-
flash applications, color (RGB) LEDs, and infrared
(IR) diodes for remotes. In series with LEDs, bal-
last resistors must be used to limit the LED current.
The LED current will vary with supply voltage and
LED forward voltage. Most types of LEDs have for-
ward voltage specifications ranging from 2.0V to
5.0V. Calculate the necessary ballast resistor value
from the following formula:
Where:
R
LED
is the resistance of resistor to be placed in
series with the LED (
).
V
IN
is the input supply voltage to the device (V).
V
F
is the forward voltage of the LED (V).
R
DS(ON)
is the resistance of the switch when it is
turned on (
).
I
LED
is the desired operating current of the LED (A).
R
LED
=
- R
DS(ON)
(V
IN
- V
F
)
I
LED
Figure 6: GPIO I/O Expander (Condense Five GPIO Control Lines to One Using AAT4296).
Circuit 1
30mA
Circuit 2
30mA
Circuit 3
30mA
Circuit 4
30mA
Circuit 5
30mA
System
Controller
GPIO 1
GPIO 2
GPIO 3
GPIO 4
GPIO 5
VIN
VIN
VIN
VIN
VIN
GPIO 2
to
GPIO 5
are now free for
other uses
IN
OUT1
OUT2
OUT3
OUT4
OUT5
AAT4296
Low Dropout
Voltage
Regulator
EN/SET
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
15
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
16
4296.2005.10.1.0
Ordering Information
Package Information
SC70JW-8
All dimensions in millimeters.
0.225
0.075
0.45
0.10
0.05
0.05
2.10
0.30
2.00
0.20
7
3
4
4
1.75
0.10
0.85
0.15
0.15
0.05
1.10 MAX
0.100
2.20
0.20
0.048REF
0.50 BSC 0.50 BSC 0.50 BSC
All AnalogicTech products are offered in Pb-free packaging. The term "Pb-free" means
semiconductor products that are in compliance with current RoHS standards, including
the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more
information, please visit our website at http://www.analogictech.com/pbfree.
Package
Marking
1
Part Number (Tape and Reel)
2
SC70JW-8
QIXYY
AAT4296IJS-T1
TSOPJW-12
QEXYY
AAT4298ITP-T1
1. XYY = assembly and date code.
2. Sample stock is generally held on part numbers listed in
BOLD.
TSOPJW-12
All dimensions in millimeters.
0.20 + 0.10
- 0.05
0.055
0.045
0.45
0.15
7
NOM
4
4
3.00
0.10
2.40
0.10
2.85
0.20
0.50 BSC 0.50 BSC 0.50 BSC 0.50 BSC 0.50 BSC
0.15
0.05
0.9625
0.0375
1.00
+ 0.10
-
0.065
0.04 REF
0.010
2.75
0.25
AAT4296/98
Five/Six Channel Push/Pull I/O Expander
4296.2005.10.1.0
17
Advanced Analogic Technologies, Inc.
830 E. Arques Avenue, Sunnyvale, CA 94085
Phone (408) 737-4600
Fax (408) 737-4611
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rights, or other intellectual property rights are implied.
AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice, and advise customers to obtain the latest
version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale
supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability.
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other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily
performed.
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