AH1898

AH1898
PROGRAMMABLE MICROPOWER OMNIPOLAR HALL-EFFECT SWITCH
Description
Pin Assignments
The AH1898 is a micropower magnetic range selectable (Bop/Brp)
Omnipolar Hall effect switch IC with internal pull up and pull down
capability, designed for portable and battery powered consumer
equipment such as cellular phones and portable PCs. To support
battery powered equipment and low voltage microcontrollers, the
(Top View)
AH1898 can operate over the supply range of 1.6V to 3.6V and uses
(Bottom View)
a hibernating clocking system to minimize the power consumption.
NEW PRODUCT
The average supply current is only 4.3µA typical at 1.80V. The
AH1898 has an 8kV ESD rating on the supply and output pins. To
minimize PCB space the AH1898 is packaged in the small
CSP package (0.81mm x 0.81mm typical).
The output is activated with either a north or south pole of sufficient
magnetic field strength. The user can select one of two magnetic
sensitivity bands via the BSEL pin without the addition of any external
components allowing a flexible but small solution. The band select
U-WLB0808-4
can be hardwired or be changed on the fly via a logic source such as
a micro-controller. When the magnetic flux density (B) perpendicular
to the package is larger than operate point (Bop), the output will be
turned on (pulled low) and held until B is lower than release point
(Brp). The output will remain off when there is no magnetic field.
Features
Applications

Omnipolar Operation (North or South pole)

Open and Close Detect for Cellular Phones

Programmable Operate and Release Points

Holster or Cover Detect for Cellular Phones and Tablet PCs

Supply Voltage of 1.6V to 3.6V

Cover or Display Switch in Portable PCs

Micropower Operation

Digital Still, Video Cameras and Handheld Gaming Consoles

Chopper Stabilized Design Provides

Proximity and Position Switches

Superior Temperature Stability

Minimal Switch Point Drift

Enhanced Immunity to Physical Stress

No External Pull-up Resistors Required

Good RF Noise Immunity

-40°C to +85°C Operating Temperature

8kV Human Body Model ESD Capability

Miniature U-WLB0808-4 (CSP 0.81mm x 0.81mm typical)

Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)

Halogen and Antimony Free. “Green” Device (Note 3)
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl)
and <1000ppm antimony compounds.
AH1898
Document number: DS36028 Rev. 1 - 2
1 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
NEW PRODUCT
Typical Applications Circuit
Note:
4. CIN is for power stabilization and to strengthen the noise immunity, the recommended capacitance is 100nF typical.
Pin Descriptions
Package: U-WLB0808-4
Pin Number
Pin Name
A1
BSEL
Band Select Pin to select operating and release gauss points
Function
A2
GND
Ground Pin
B1
VDD
Power Supply Input
B2
OUTPUT
Output Pin
Functional Block Diagram
AH1898
Document number: DS36028 Rev. 1 - 2
2 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
Absolute Maximum Ratings (Note 5) (@TA = +25°C, unless otherwise specified.)
Symbol
Rating
Unit
VDD
Supply Voltage (Note 6)
6
V
VDD_REV
Reverse Supply Voltage
-0.3
V
IOUTPUT
B
Output Current (source and sink)
2.5
mA
Magnetic Flux Density
Storage Temperature Range
TJ
Maximum Junction Temperature
Notes:
Unlimited
Package Power Dissipation
PD
Ts
ESD HBM
NEW PRODUCT
Parameter
U-WLB0808-4
160
°C
150
°C
8
kV
6
kV
VDD, GND and OUT pins
BSEL pin
Human Body Model (HMB) ESD capability
mW
-65 to +150
5. Stresses greater than the 'Absolute Maximum Ratings' specified above may cause permanent damage to the device. These are stress ratings only;
functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability may be
affected by exposure to absolute maximum rating conditions for extended periods of time.
6. The absolute maximum VDD of 6V is a transient stress rating and is not meant as a functional operating condition. It is not recommended to
operate the device at the absolute maximum rated conditions for any period of time.
Recommended Operating Conditions (@TA = +25°C, unless otherwise specified.)
Symbol
VDD
TA
Conditions
Rating
Unit
Supply Voltage
Parameter
Operating
1.6V to 3.6V
V
Operating Temperature Range
Operating
-40 to +85
C
Electrical Characteristics (@TA = +25°C, VDD = 1.8V, unless otherwise specified.)
Symbol
Parameter
Conditions
VOL
Output Low Voltage (on)
IOUT = 1mA
VOH
Output High Voltage (off)
IOUT = -1mA
Min
Typ
Max
—
0.1
0.2
V
—
V
V
VDD -0.2 VDD -0.1
Unit
VSEL_LB
Bans select voltage for low band
0
—
0.5
VSEL_HB
Bans select voltage for high band
1.4
—
3.6
V
RPU_BSEL
BSEL pin internal pull-up resistor
(Note 7)
—
50
—
kΩ
During ‘awake’ period
—
2.1
—
mA
During ‘sleep’ period
—
2.5
—
mA
VDD = 1.8V
—
4.3
8
µA
VDD = 3.6V
—
7.2
13
µA
(Note 8)
(Note 8)
—
—
50
50
100
100
µs
ms
—
0.1
—
%
—
100.0
200.1
ms
IDD(awake)
IDD(sleep)
Supply Current
IDD(avg)
Average Supply Current
Tawake
Tperiod
Awake Time
Period
D.C.
Duty Cycle
tBAND
Band transition time
Notes:
(Note 9)
7. BSEL pin internal pull-up resistor is only active during AWAKE time.
8. When power is initially turned on, the operating VDD (1.6V to 3.6V) must be applied to guarantee the output sampling.
The output state is valid after the second operating phase (typical 100ms).
9. Transition time varies dependant on the timing of BSEL activation during the sleep and awake phases.
AH1898
Document number: DS36028 Rev. 1 - 2
3 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
Magnetic Characteristics (Note 10 & 11) (TA = +25°C, VDD = 1.6V to 3.6V, unless otherwise specified)
NEW PRODUCT
BSEL
Symbol
Low
BopsLB (south pole to part marking side side)
Low
BopnLB (north pole to part marking side side)
Low
BrpsLB (south pole to part marking side side)
Low
BrpnLB (north pole to part marking side side)
High
BopsHB (south pole to part marking side side)
High
BopnHB (north pole to part marking side side)
High
BrpsHB (south pole to part marking side side)
High
BrpnHB (north pole to part marking side side)
Bhy (|Bopx|-|Brpx|)
Notes:
Characteristics
Low Band - Operation Point
Low Band - Release Point
High Band - Operation Point
High Band - Release Point
Hysteresis
Min
Typ
(1mT=10 Gauss)
Max
Unit
18
35
55
-55
-35
-18
12
25
45
-45
-25
-12
43
60
80
-80
-60
-43
35
50
70
-70
-50
-35
—
10
—
Gauss
10. Typical data is at TA = +25C, VDD = 1.8V.
11. Magnetic characteristics may vary with operating temperature and after soldering.
The AH1898 includes a band select pin (BSEL) so that the operate (Bops and Bopn) and release (Brps and Brpn) points can be adjusted between
two pre-defined ranges. The BSEL can be hard wired within the application circuit or the band can be selected on the fly by using the BSEL pin as
a logic input. This feature allows the AH1898 sensitivity to be changed by firmware within the application without the addition of any external
components. If the BSEL pin is left open circuit the AH1898 defaults to high band.
AH1898
Document number: DS36028 Rev. 1 - 2
4 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
Application Note
Applications Circuit One – Low Band
Connecting the BSEL pin to ground permanently configures the AH1898 into its high sensitivity mode, requiring a reduced magnetic flux density
NEW PRODUCT
to activate its output (Low Band).
Applications Circuit Two – High Band
Connecting the BSEL pin to VDD or to a voltage greater than 1.4V or leaving the BSEL pin unconnected configures the AH1898 into its low
sensitivity mode, requiring a higher magnetic flux density to activate its output (High Band).
Applications Circuit Three – Adjustable Sensitivity
To enhance flexibility within the application, the sensitivity can be adjusted with a standard logic signal allowing it to be controlled by a microcontroller or a logic source. This allows the sensitivity to be changed within the application without a hardware change. Whenever the sensitivity
band selection is changed, the band selection changeover should be allowed to complete for the output to be valid.
AH1898
Document number: DS36028 Rev. 1 - 2
5 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
Application Note (cont.)
Bands Select Change Timing and Valid Output
Whenever band selection BSEL pin input is changed, allow for band selection changeover to complete and stabilize. The output is valid only
NEW PRODUCT
after the second complete operating ‘awake’ phase. Time taken for the output to be valid, after the BSEL change, depends on timing of BSEL
change during the sleep and awake phase; this transition time (tBAND) can range from 100ms typical and 200.1ms maximum.
AH1898
Document number: DS36028 Rev. 1 - 2
6 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
Typical Operating Characteristics
Typical switch points characteristics in low band (BSEL = Low) and high band (BSEL = High)
VDD = 1.80V, BSEL = Low (GND)
80
60
Bops
Brps
Bhy
20
0
-20
Brpn
Bopn
-40
40
Gauss (G)
Gauss (G)
Bops
Brps
60
40
NEW PRODUCT
VDD = 1.80V, BSEL = High (VDD )
80
20
Bhy
0
-20
-40
-60
Brpn
Bopn
-60
-80
-80
‐50
‐25
0
25
50
75
-50
100
-25
0
Temperature (Ԩ)
Switch Points vs. Temperature
100
Bops
Brps
60
Bops
Brps
Bhy
20
0
Brpn
Bopn
-20
-40
40
Gauss (G)
40
Gauss (G)
75
V DD = 3.30V, BSEL = High (V DD )
80
60
20
Bhy
0
‐20
‐40
-60
Brpn
Bopn
‐60
-80
-50
-25
0
25
50
75
‐80
100
-50
-25
0
25
50
75
Temperature (Ԩ)
Temperature (Ԩ)
Switch Points vs. Temperature
Switch Points vs. Temperature
TA = +25oC, BSEL = Low (GND)
80
Bops
Brps
60
Bops
Brps
Bhy
20
0
Brpn
Bopn
-20
-40
-60
40
Gauss (G)
40
20
Bhy
0
‐20
‐40
Brpn
Bopn
‐60
-80
1.5
1.8
2.1
2.4
2.7
3
3.3
3.6
3.9
‐80
Supply voltage (V)
Document number: DS36028 Rev. 1 - 2
1.5
1.8
2.1
2.4
2.7
3
3.3
3.6
3.9
Supply voltage (V)
Switch Points vs. Supply Voltage
AH1898
100
TA = +25oC, BSEL = High (VDD )
80
60
Gauss (G)
50
Switch Points vs. Temperature
VDD = 3.30V, BSEL = Low (GND)
80
25
Temperature (Ԩ )
Switch Points vs. Supply Voltage
7 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
Typical Operating Characteristics (cont.)
V DD = 1.80V and 3.60V
10
9
8
3.6V
7
6
5
1.8V
4
3
2
1
0
-50
-25
0
25
50
75
100
Avg. Supply Current IDD(avg) (uA)
Avg. Supply Current IDD(avg) (uA)
NEW PRODUCT
Average Supply Current IDD(avg)
TA = +25oC
10
9
8
7
6
5
4
3
2
1
0
Temperature (Ԩ)
1.5
1.8
2.1
2.4
2.7
3
3.3
3.6
3.9
Supply voltage (V)
Average Supply Current vs. Temperature
Average Supply Current vs. Supply Voltage
Ordering Information
Part Number
Package
Code
Packaging
AH1898-CA4-7
CA4
U-WLB0808-4
7” Tape and Reel
Quantity
Part Number Suffix
3000/Tape & Reel
-7
Marking Information
(1)
Package Type: U-WLB0808-4
Part Number
AH1898-CA4-7
AH1898
Document number: DS36028 Rev. 1 - 2
Package
U-WLB0808-4
8 of 11
www.diodes.com
Identification Code
B8
February 2013
© Diodes Incorporated
AH1898
Package Outline Dimensions (All dimensions in mm.)
Please see AP02002 at http://www.diodes.com/datasheets/ap02002.pdf for latest version.
(1)
Package Type: U-WLB0808-4
D
e
D
I
1
#
N
I
P
4
X
b
Ø
NEW PRODUCT
e
E
︵
︶
2
A
A
U-WLB0808-4
Dim Min Max Typ
A
0.511 REF
A2 0.336 0.366 0.351
A3
0.15 0.17 0.16
b
0.205 0.225 0.215
D
0.795 0.825 0.81
E
0.795 0.825 0.81
e
0.40
All Dimensions in mm
3
A
E
N
A
L
P
G
N
I
T
A
E
S
Sensor Location
Suggested Pad Layout
Please see AP02001 at http://www.diodes.com/datasheets/ap02001.pdf for the latest version.
(1)
Package Type: U-WLB0808-4
X
4
D
Ø
C
U-WLB0808-4
Dimensions
Value
C
0.40
D
0.172
All Dimensions in mm
C
AH1898
Document number: DS36028 Rev. 1 - 2
9 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
Taping Orientation
NEW PRODUCT
Package Type: U-WLB0808-4
AH1898
Document number: DS36028 Rev. 1 - 2
10 of 11
www.diodes.com
February 2013
© Diodes Incorporated
AH1898
IMPORTANT NOTICE
DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
(AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION).
NEW PRODUCT
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes
without further notice to this document and any product described herein. Diodes Incorporated does not assume any liability arising out of the
application or use of this document or any product described herein; neither does Diodes Incorporated convey any license under its patent or
trademark rights, nor the rights of others. Any Customer or user of this document or products described herein in such applications shall assume
all risks of such use and will agree to hold Diodes Incorporated and all the companies whose products are represented on Diodes Incorporated
website, harmless against all damages.
Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized sales channel.
Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall indemnify and
hold Diodes Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees arising out of, directly or
indirectly, any claim of personal injury or death associated with such unintended or unauthorized application.
Products described herein may be covered by one or more United States, international or foreign patents pending. Product names and markings
noted herein may also be covered by one or more United States, international or foreign trademarks.
This document is written in English but may be translated into multiple languages for reference. Only the English version of this document is the
final and determinative format released by Diodes Incorporated.
LIFE SUPPORT
Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without the express
written approval of the Chief Executive Officer of Diodes Incorporated. As used herein:
A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body, or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the
labeling can be reasonably expected to result in significant injury to the user.
B. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the
failure of the life support device or to affect its safety or effectiveness.
Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or systems, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any
use of Diodes Incorporated products in such safety-critical, life support devices or systems, notwithstanding any devices- or systems-related
information or support that may be provided by Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporated and its
representatives against any damages arising out of the use of Diodes Incorporated products in such safety-critical, life support devices or systems.
Copyright © 2013, Diodes Incorporated
www.diodes.com
AH1898
Document number: DS36028 Rev. 1 - 2
11 of 11
www.diodes.com
February 2013
© Diodes Incorporated