Diodes AH1892 User Manual

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

Description

The AH1892 is a micropower magnetic range selectable (Bop/Brp)
Omnipolar Hall effect switch IC with internal pull up and pull down
capability, designed for consumer equipment ranging from portable
and battery powered cellular phones and portable PCs to home
appliances and industrial applications. To support battery powered
equipment and low voltage microcontrollers, the AH1892 can operate
over the supply range of 1.6V to 3.6V and uses a hibernating clocking
system to minimize the power consumption. The average supply
current is only 4.3µA typical at 1.80V. Due to the application diversity,
the AH1892 has an 8kV ESD rating on the supply and output pins. To
minimize PCB space the AH1892 is packaged in the small CSP
package (0.71mm x 0.71mm) or SOT553 leaded package

The output is activated with either a north or south pole of sufficient
magnetic field strength. The user can select one of two magnetic

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sensitivity bands via the BSEL pin without the addition of any external
components allowing a flexible but small solution. The band select
can be hardwired or be changed on the fly via a logic source such as
a micro-controller. When the magnetic flux density (B) is larger than
operate point (Bop), the output will be turned on (pulled low) and held
until B is lower than release point (Brp).

Features

• Omnipolar operation (North or South pole)

• Programmable operate and release points

• Supply voltage of 1.6V to 3.6V

• Micropower operation

• Chopper stabilized design

 Superior temperature stability
 Extremely Low Switch-Point Drift
 Insensitive to Physical Stress

• No external pull up resistors required

• Good RF noise immunity

• -40°C to +85°C operating temperature

• 8kV ESD on supply and output pins

• Miniature U-WLB07070-4 (CSP 0.71mm x 0.71mm typical) and
small low profile SOT553

• 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.

AH1892

Document number: DS35092 Rev. 1 - 2

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.

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Pin Assignments

U-WLB0707-4

SOT553

Applications

• Open and close detect for gaming and cellular phones

• Holster and dock detect for cellular phones

• Cover switch in portable and tablet PCs

• Digital still and video cameras

• Tray, door and covers position detect for printers and scanners

• Contact-less switch in consumer and industrial products

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AH1892

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Typical Application Circuit

AH1892

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

Note : C

is for power stabilization and to strengthen the noise immunity, the recommended capacitance is 100nF typical

IN

Pin Descriptions

Package: U-WLB0707-4

NEW PRODUCT

Pin # Pin Name Description

A1 GND Ground
A2 OUTPUT Output
B1 BSEL Band Select

V

B2

Package: SOT553

Pin # Pin Name Description

1
2 NC No Connection (Note 4)
3 BSEL Band Select
4 GND Ground
5 OUTPUT Output

Notes: 4. NC is “No Connection” pin and is not connected internally. This pin can be left open or connected to ground.

DD

V

DD

Power Supply Voltage

Power Supply Voltage

Functional Block Diagram

AH1892

Document number: DS35092 Rev. 1 - 2

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AH1892

V

Absolute Maximum Ratings (T

Symbol Characteristics

VDD

V

DD REV

I

OUTPUT

B Magnetic Flux Density Unlimited

Ts Storage Temperature Range -65 to +150 °C

PD

TJ

ESD Human Body Model ESD

Notes: 5. Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are stress ratings

NEW PRODUCT

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 V

operate the device at the absolute maximum rated conditions for any period of time.

Supply Voltage (Note 6) 6 V
Reverse Supply Voltage -0.3 V

Output current (source and sink) 2.5 mA

Package Power Dissipation

Maximum Junction Temperature 150 °C

of 6V is a transient stress rating and is not meant as a functional operating condition. It is not recommended to

DD

Recommended Operating Conditions

Symbol Characteristics Conditions Rating Unit

VDD

TA

Supply Voltage Operating 1.6 to 3.6 V

Operating Temperature Range Operating -40 to +85 °C

Electrical Characteristics (T

Symbol Characteristics Conditions Min Typ Max Unit

VOL

VOH

BLsel Band select low band 0 0.5 V

BHsel Band select high band 1.4 3.6 V

R

U_BSEL

IDD(awake)

IDD(sleep)

IDD(avg)
IDD(avg) VDD = 3.6V
Tawake Awake active pulse width (Note 8) 50 100 µs

Tperiod Awake period (Note 8) 50 100 ms

D.C. Duty cycle 0.1 %

TBand Band transition time ( Note 9) 100.0 200.1 ms

Notes: 7. BSEL pin internal pull-up resistor is only active during AWAKE time.
The output state is valid after the second operating phase (typical 100ms).

AH1892

Document number: DS35092 Rev. 1 - 2

Output low voltage (on)
Output high voltage (off)

BSEL pin internal pull-up resistor (Note 7) 50 kΩ

Supply current

Average cupply current

8. When power is initially on, the operating V

9. Transition time varies dependant on the timing of BSEL activation during the sleep and awake phases.

= +25°C, Note 5)

A

= +25°C, V

A

(1.6V to 3.6V) must be applied to guarantee the output sampling.

DD

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

alues Unit

U-WLB0707-4 160 mW
SOT553 230 mW

, GND and OUT pins

V

DD

BSEL pin 6 kV

= 1.8V, unless otherwise specified.)

DD

I

= 1mA

OUT

I

= -1mA V

OUT

During ‘awake’ period 2.1 mA

During ‘sleep’ period 2.5 µA

VDD = 1.8V

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0.1 0.2 V

-0.2 V

DD

4.3 8.0 µA

7.2 13.0 µA

8 kV

DD

-0.1

V

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© Diodes Incorporated

AH1892

Electrical Characteristics (cont.)

IDD(awake)

IDD(sleep)

0

Magnetic Characteristics (T

(1mT=10 Gauss)

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BSEL Symbol Characteristics Min Typ Max Unit

Low
Low
Low

Low
High
High
High
High

Notes: 10. Magnetic characteristics may vary with operating temperature and after soldering.

The AH1892 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 AH1892 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 AH1892 defaults to high band.

BopsLB(south pole to brand side)
BopnLB (north pole to brand side)
BrpsLB (south pole to brand side)
BrpnLB (north pole to brand side)
BopsHB(south pole to brand side)
BopnHB (north pole to brand side)
BrpsHB (south pole to brand side)
BrpnHB (north pole to brand side)

- Bhy (|Bopx|-|Brpx|) Hysteresis - 10 -

AH1892

Document number: DS35092 Rev. 1 - 2

= +25°C, V

A

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

Tperiod

Tawake

Tsleep

Sample and output

latched

= 1.6V to 3.6V, Note 10)

DD

Low Band - Operation Point

Low Band - Release Point

High Band - Operation Point

High Band - Release Point

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18 35 55

-55 -35 -18
12 25 45

-45 -25 -12
43 60 80

-80 -60 -43
35 50 70

-70 -50 -35

© Diodes Incorporated

Gauss

May 2012

AH1892

Application Note

Applications Circuit One – Low Band

Connecting the BSEL pin to ground permanently configures the AH1892 into its high sensitivity mode, requiring a reduced magnetic flux
density to activate its output (Low Band).

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

NEW PRODUCT

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 AH1892 int o 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.

AH1892

Document number: DS35092 Rev. 1 - 2

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AH1892

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
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 time can range from 100ms typical and 200.1ms maximum.

NEW PRODUCT

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

AH1892

Document number: DS35092 Rev. 1 - 2

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AH1892

A

G

U

G

GAU

G

GAU

G

R

G

U

P

PLY CUR

REN

T

R

G

U

P

PLY CUR

R

N

T

Typical Operating Characteristics

Typical switch points characterisitics in low band (BSEL = Low) and high band (BSEL = High)

NEW PRODUCT

Average Supply Current I

AH1892

Document number: DS35092 Rev. 1 - 2

70

V = 1.80 V, BSEL = Low (GND)

DD

60
50

40

Bops

Brps

30
20
10

0

USS (G)

-10

G

-20

Brpn

Bhys

-30

-40

-50

Bopn

-60

-70

-50-250 255075100
TEMPERATURE (°C)

Switch Points vs. Temperature

70
60
50
40
30
20

)

10

0

SS (

-10

-20

-30

-40

-50

-60

-70

1.5 1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOL TAGE (V)

Switc h Points vs . S u pply Vo l tage

(avg)

10

9
8

DD

7

, I (avg)d (µA)

V = 1.8V and 3.6V

DD

DD

3.6V

6
5

1.8V

4
3

E S

2

A

1
0

AVE

-50 -25 0 25 50 75 100
TEMPERATURE (°C)

Average Supply Curr ent vs. Temperatur e

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

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70

V = 1.80V, BSEL = High (V )

DD DD

60
50

40
30
20

)

10

0

SS (
A

-10

-20

-30

-40

-50

-60

-70

-50-250 255075100
TEMPERATURE (°C)

Switch Points vs. Temperature

70
60
50
40

Bops

30
20

)

10

0

SS (

-10

-20

T = +25°C,

A

-30

BSEL = High (V )

-40

DD

Brpn

-50

-60

-70

1.5 1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)

Switch Points vs. Supply Voltage

10

9
8

DD

7

, I (avg) (µA)

6

E

5
4

3

E S

2

A

1

AVE

0

1.5 1.8 2.1 2.4 2.7 3.0 3.3 3.6
SUPPLY VOLTAGE (V)

Average Supply Current vs. Supply Voltage

Bops

Brps

Bhys

Brpn

Bopn

Brps

Bhys

Bopn

T = +25°C

A

May 2012

© Diodes Incorporated

Ordering Information

AH1892

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

Device Package Code

AH1892-CD4-7 CD4 U-WLB0707-4 3000/Tape & Reel -7

NEW PRODUCT

AH1892-Z-7 Z SOT553 3000/Tape & Reel -7

Notes: 11. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at

http://www.diodes.com/datasheets/ap02001.pdf.

Packaging

(Note 11)

Quantity Part Number Suffix

Marking Information

(1) Package type: U-WLB0707-4

Part Number Package Identification Code

AH1892-CD4-7 U-WLB0707-4 B2

(2)

Package type: SOT553

7” Tape and Reel

Part Number Package Identification Code

AH1892-Z-7 SOT553 B2

AH1892

Document number: DS35092 Rev. 1 - 2

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May 2012

Package Outline Dimensions (All Dimensions in mm)

(1) Package type: U-WLB0707-4

NEW PRODUCT

AH1892

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

AH1892

Document number: DS35092 Rev. 1 - 2

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May 2012

Package Outline Dimensions (cont.)

(2) Package type: SOT553

AH1892

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

NEW PRODUCT

1.50/1.70

Pin1

°

1.0Typ.

A

0.1

0.5Typ.

C

L

Hall Sensor

0.15/0.30(5x)

B

D

D

0.30 C

0.45/0.67

C

L

1.55/1.70

1.10/1.25

0.30 C

6

°

~8

6

°

~

8

°

0.30 C D

0.10/0.18

0.30±0.08

0.10

0.55/0.62

°

8

~

°
6

Die

M C A-B D

1.0Typ.

C

L

5x-0.5

C

L

1.2

Pin1

0.5Typ.

Land Pattern Recommendation

(Unit:mm)

0.3

Top View

1.7

2.2

AH1892

Document number: DS35092 Rev. 1 - 2

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© Diodes Incorporated

AH1892

PROGRAMMABLE MICROPOWER OMNIPOLAR

HALL-EFFECT SENSOR SWITCH

NEW PRODUCT

IMPORTANT NO TICE

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).

Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvem ents, 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 produc t 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 uni ntended 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.

LIFE SUPPORT

Diodes Incorporated products are specifically not authorized for use as critic al 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 regulat ory 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 ari sing out of the use of Diodes
Incorporated products in such safety-critical, life support devices or systems.

Copyright © 2012, Diodes Incorporated

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AH1892

Document number: DS35092 Rev. 1 - 2

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