19-6310; Rev 0; 5/12
EVALUATION KIT AVAILABLE
MAX14627/MAX14628
Low-Power Headset Detectors with
SEND/END Button Support
General Description
The MAX14627/MAX14628 provide a simple solution for
detecting the insertion and managing the operation of a
3.5mm stereo headset with a microphone. These devices
integrate all circuitry needed to detect SEND/END button
press events and generate required microphone bias volt-
ages, and are fully compatible with Windows Mobile 7.
The devices need only three GPIOs from the host control-
ler to select between call mode and standby mode, and
monitor the SEND/END and jack insertion status. In call
mode, the low-noise LDO is enabled to provide DC bias to
the externally preamplified microphone. In standby mode,
microphone low-power pulsing is enabled to reduce sup-
ply current while waiting for a SEND/END button press
event. Two open-drain outputs signal the host controller
when an insertion/removal or SEND/END button press
event occurs. If a 3P headset without a microphone is
inserted, the low-power pulsing can be disabled by setting
the MODE input to high impedance.
The MAX14627 operates from a 2.5V to 5.5V input voltage
supply and features an internal 2.2V LDO output, while the
MAX14628 operates from a 3.1V to 5.5V voltage supply
and features an internal 2.8V LDO output voltage. Both
devices control jack insertion detection by monitoring a
3.5mm socket with a normally open jack insertion switch.
Additionally, the MAX14628 features open microphone
detection.
The MAX14627/MAX14628 are available in an 8-pin TDFN
package, and are fully specified over the -40NC to +85NC
extended temperature range.
Benefits and Features
S
Versatile Jack Detection and Control
MODE Three-State Microphone Bias Control
MIC Switch Ground Detection (MAX14627)
MIC Switch Open and Ground Detection
(MAX14628)
S
Compatible with Windows Mobile 7 and Google
Android
Microphone Button Press Detection
S
High-Performance MIC Bias and Power Savings
No Pop-Up Noises
Ultra-Low Noise, High-PSRR MIC Bias
Low-Power MIC Idle Mode
Automatic Ultra-Low-Power Mode When
Microphone Is Disabled
S
PCB Space and Cost Savings
Integrated ±15kV ESD Protection (HBM) on
DETIN and MIC Input Terminals
Small 8-Pin (2mm x 2mm) TDFN Package
Applications
Cell Phones
Portable Media Players
Tablet/Laptop PCs
Ordering Information
appears at end of data sheet.
For related parts and recommended products to use with this part,
refer to
www.maxim-ic.com/MAX14627.related.
Windows Mobile is a registered trademark of Microsoft Corporation.
Typical Operating Circuits
V
CC
1µF
MIC
AUDIO DIRECT
DRIVE
Typical Operating Circuits continued
at end of data sheet.
MODE
V
IO
1MI
PROCESSOR
V
IO
1MI
DET
SWD
V
CC
CAP
1µF
RES
MAX14628
MIC
2.2kI
MIC
LEFT
DET
SEND/
END
MICROPHONE
EP/GND
DETIN
RIGHT
GND
½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½
Maxim Integrated Products
1
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.
MAX14627/MAX14628
Low-Power Headset Detectors with
SEND/END Button Support
ABSOLUTE MAXIMUM RATINGS
(Voltages referenced to GND.)
V
CC
, MODE, SWD, DET ..........................................-0.3V to +6V
CAP, MIC, RES ......................................... -0.3V to (V
CC
+ 0.3V)
DETIN .........................................................................-6V to +6V
Continuous Current into Any Terminal ..........................
Q100mA
Continuous Power Dissipation (T
A
= +70NC)
TDFN (derate 11.9mW/NC above +70NC) .................953.5mW
Operating Temperature Range .......................... -40NC to +85NC
Junction Temperature .....................................................+150NC
Storage Temperature Range............................ -65NC to +150NC
Lead Temperature (soldering, 10s) ...............................+300NC
Soldering Temperature (reflow) ......................................+260NC
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional opera-
tion 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.
PACKAGE THERMAL CHARACTERISTICS (Note 1)
TDFN
Junction-to-Ambient Thermal Resistance (q
JA
) .......83.9°C/W
Junction-to-Case Thermal Resistance (q
JC
) ...................37°C/W
Note 1:
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.
ELECTRICAL CHARACTERISTICS
(V
CC
= 2.5V to 5.5V for MAX14627, V
CC
= 3.1V to 5.5V for MAX14628, C
DETIN
< 100pF, T
A
= -40NC to +85NC, unless otherwise noted.
Typical values are at V
CC
= +3.6V, T
A
= +25NC.) (Note 2)
PARAMETER
DC CHARACTERISTICS
Supply Voltage Range
V
CC
Undervoltage-Lockout
Threshold
V
CC
V
CCUVLO
MAX14627
MAX14628
V
CC
rising
MODE = low,
DETIN = high
MAX14627,
V
CC
= 2.8V
MODE = low,
DETIN = low, I
MIC
= 300FA
MODE = high,
DETIN = low, I
MIC
= 300FA
MODE = high-Z,
DETIN = low
MODE = low,
DETIN = high
MAX14628,
V
CC
= 3.3V
MODE = low,
DETIN = low, I
MIC
= 300FA
MODE = high,
DETIN = low, I
MIC
= 300FA
MODE = high-Z,
DETIN = low
2.5
3.1
0.9
1.7
5.5
5.5
2.45
1.3
11.7
800
6.0
FA
1.9
13.2
800
7.0
V
V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
CC
Supply Current
I
CC
½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½
Maxim Integrated Products
2
MAX14627/MAX14628
Low-Power Headset Detectors with
SEND/END Button Support
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 2.5V to 5.5V for MAX14627, V
CC
= 3.1V to 5.5V for MAX14628, C
DETIN
< 100pF, T
A
= -40NC to +85NC, unless otherwise noted.
Typical values are at V
CC
= +3.6V, T
A
= +25NC.) (Note 2)
PARAMETER
DETIN Pullup Resistance
DETIN Series Resistance
Negative Current from DETIN
MIC SEND/END Detection
Threshold
MIC Open Switch Detection
Threshold
DETIN Detection Threshold
MODE Pullup Resistance for
High-Z Detection
MODE Pulldown Resistance for
High-Z Detection
LINEAR REGULATOR (CAP)
Output Current Limit
LDO Output Voltage
I
CAP
V
LDO
V
CAP
= 0V
MAX14627, V
CC
= 2.8V
MAX14628, V
CC
= 3.3V
Noise from V
CC
to CAP, f = 217Hz,
V
CC
= 2.8V ±0.1V, I
CAP
= 300FA,
MODE = high
V
CC
= 2.8V, I
MIC
= 300FA,
f = 100Hz to 4000Hz
MAX14627, V
CC
= 2.8V, R
L
= 2kI,
V
CAP
from 90% to 10%
MAX14628, V
CC
= 3.3V, R
L
= 2kI,
V
CAP
from 90% to 10%
(Note 3)
0.22
1.4
0.4
Pulsing with 1/64 duty cycle from MODE
terminal when MODE = low, DETIN = low
(Note 4)
When MODE = high, DETIN = low
When MODE = high-Z (Note 3)
V
OH
= 5V
120
-1
220
1
380
+1
1
4
2.0
2.55
2.2
2.8
100
2.45
3.1
mA
V
SYMBOL
R
DETIN
R
DETININT
I
NDETIN
V
MICTH_LOW
V
MICTH_HI
V
DETINTH
R
MODE_HI
R
MODE_LO
MAX14628
Falling edge
V
DETIN
= -2V
0.20 x
V
BIAS
0.90 x
V
BIAS
1/3 x
V
CC
0.22 x
V
BIAS
0.94 x
V
BIAS
1/2 x
V
CC
200
200
CONDITIONS
MIN
TYP
1000
100
31
0.24 x
V
BIAS
0.98 x
V
BIAS
2/3 x
V
CC
MAX
UNITS
kI
kI
FA
V
V
V
kI
kI
LDO PSRR
PSRR
LDO
N
LDO
dB
LDO Noise
11
60
FV
RMS
LDO Turn-Off Time
t
LDO_OFF
C
OUT
V
IH
V
IL
I
MODE_LOW
R
MODE_HI
I
MODE_LKG
I
OH_LKG
Fs
60
FF
V
V
FA
kI
FA
FA
Minimum Bypass Capacitance
Input Logic-High Voltage
Input Logic-Low Voltage
MODE Average Current
MODE Input Resistance
MODE External Maximum
Leakage
Output Logic-High Leakage
Current (Open Drain)
DIGITAL SIGNALS (MODE, SWD, DET)
½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½
Maxim Integrated Products
3
MAX14627/MAX14628
Low-Power Headset Detectors with
SEND/END Button Support
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= 2.5V to 5.5V for MAX14627, V
CC
= 3.1V to 5.5V for MAX14628, C
DETIN
< 100pF, T
A
= -40NC to +85NC, unless otherwise noted.
Typical values are at V
CC
= +3.6V, T
A
= +25NC.) (Note 2)
PARAMETER
Output Logic-Low Voltage
DYNAMIC CHARACTERISTICS
MODE Maximum Load
Capacitance
MIC Low-Power Mode On-Time
MIC Low-Power Mode Period
High-Z Detection Time
MODE 0
→
1 Detection Time
MODE 1
→
0 Detection Time
DETIN Debounce Time
SEND/END Debounce Time
ESD PROTECTION
MIC, DETIN
All Other Pins
Human Body Model
Human Body Model
±15
±2
kV
kV
C
MODE
t
MICLPO
t
MICLPP
t
HIZDET
t
MODE0-1
t
MODE1-0
t
DIDEB
t
SEDEB
Falling edge
(Note 3)
120
8
16
4
16
300
30
200
pF
Fs
ms
ms
ms
ms
ms
ms
SYMBOL
V
OL
I
SINK
= 1mA
CONDITIONS
MIN
TYP
MAX
0.4
UNITS
V
Note 2:
All devices are production tested at T
A
= +25°C. Specifications over temperature are guaranteed by design.
Note 3:
External specification requirements.
Note 4:
Guaranteed by design.
Typical Operating Characteristics
(V
CC
= 3.3V, T
A
= +25NC, C
DETIN
< 100pF, unless otherwise noted.)
V
CC
SUPPLY CURRENT vs. VOLTAGE
MAX14627 toc01
V
CC
SUPPLY CURRENT vs. VOLTAGE
MAX14627 toc02
V
CC
SUPPLY CURRENT vs. VOLTAGE
T
A
= +85°C
180
160
I
CC
(µA)
MAX14627 toc03
4.5
4.0
3.5
3.0
I
CC
(µA)
2.5
2.0
1.5
1.0
0.5
0
2.5
3.0
3.5
4.0
V
CC
(V)
4.5
5.0
10
9
8
7
I
CC
(µA)
6
5
4
3
200
SHUTDOWN MODE,
V
MODE
= LOW,
V
DETIN
= HIGH
T
A
= -40°C
T
A
= +25°C
T
A
= +25°C
T
A
= +85°C
140
120
100
T
A
= +25°C
T
A
= -40°C
T
A
= +85°C
2
1
0
5.5
2.5
T
A
= -40°C
MPLP MODE, I
MIC
= 0µA
V
MODE
= V
DETIN
= LOW
3.0
3.5
4.0
V
CC
(V)
4.5
5.0
5.5
80
60
2.5
3.0
CALL MODE, I
MIC
= 0µA
V
MODE
= HIGH, V
DETIN
= LOW
3.5
4.0
V
CC
(V)
4.5
5.0
5.5
½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½
Maxim Integrated Products
4
MAX14627/MAX14628
Low-Power Headset Detectors with
SEND/END Button Support
Typical Operating Characteristics (continued)
(V
CC
= 3.3V, T
A
= +25NC, C
DETIN
< 100pF, unless otherwise noted.)
MAX14627 CAP VOLTAGE vs. V
CC
MAX14627 toc04
MAX14628 CAP VOLTAGE vs. V
CC
MAX14627 toc05
2.5
2.4
2.3
2.2
2.1
3.0
2.9
2.8
2.7
2.6
V
CAP
(V)
I
CAP
= 0mA
2.0
2.5
3.0
3.5
4.0
V
CC
(V)
4.5
5.0
5.5
2.5
3.1
3.5
3.9
4.3
V
CC
(V)
4.7
V
CAP
(V)
I
CAP
= 0mA
5.1
5.5
MAX14627 CAP VOLTAGE vs. CURRENT
MAX14627 toc06
MAX14628 CAP VOLTAGE vs. CURRENT
MAX14627 toc07
3.0
2.5
2.0
V
CAP
(V)
1.5
1.0
0.5
0
0
1
2
3
4
5
6
3.0
2.5
2.0
V
CAP
(V)
1.5
1.0
V
CC
= 3.3V
0.5
0
7
0
V
CC
= 3.3V
1
2
3
4
5
6
7
I
CAP
(mA)
I
CAP
(mA)
MAX14627 CAP VOLTAGE
vs. TEMPERATURE
MAX14627 toc08
MAX14628 CAP VOLTAGE
vs. TEMPERATURE
MAX14627 toc09
2.5
2.4
2.3
2.2
2.1
2.0
-40
-15
10
T
A
(°C)
35
60
3.0
2.9
2.8
2.7
2.6
2.5
V
CAP
(V)
V
CC
= 3.3V
I
CAP
= 0mA
85
V
CAP
(V)
V
CC
= 3.3V
I
CAP
= 0mA
-40
-15
10
T
A
(°C)
35
60
85
½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½½
Maxim Integrated Products
5