HMC1023
SENSOR PRODUCTS
Duty Cycling for Lower Energy Consumption
For battery powered and other applications needing limited energy consumption, the sensor bridge and support
electronics can be switched “off” between magnetic field measurements. The HMC1023 sensors are very low
capacitance (Bandwidth > 5MHz) sensor bridges and can stabilize quickly, typically before the support electronics
can. Other energy saving ideas would be to minimize the quantity of set/reset pulses which saves energy over the
battery life. Figure 3 shows a simple supply switching circuit that can be microprocessor controlled to duty cycle
(toggle) the electronics in moderate current (<25mA) applications.
MMBT2907ALT1
PC
To Sensor Circuits
toggle
10k:
+
-
10Pf
0.01Pf
Vcc
Vcc
Gnd
*MMBD7001LT1
* Used when Vcc = 5.0 volts, jumper
when using Vcc = 3.3 volts or less.
MMBT2907ALT1
PC
To Sensor Circuits
toggle
10k:
+
-
10Pf
0.01Pf
Vcc
Vcc
Gnd
*MMBD7001LT1
* Used when Vcc = 5.0 volts, jumper
when using Vcc = 3.3 volts or less.
Off
On
Off
On
Figure 3
Duty Cycling
ORDERING INFORMATION
Part Number Package Style
HMC1023 Three Axis Magnetic Sensor
HMC1023PCB Three Axis Magnetic Sensor – 16-Pin DIP Demo
The application circuits herein constitute typical usage and interface of Honeywell product. Honeywell does not
warrant or assume liability for customer-designed circuits derived from this description or depiction.
Honeywell reserves the right to make changes to improve reliability, function or design. Honeywell does not assume
any liability arising out of the application or use of any product or circuit described herein; neither does it convey any
license under its patent rights nor the rights of others.
This product may be covered by one or more of the following U.S. Patents: 4569742 4681812 4847584 4857418
4945397 5019461 5247278 5820924 5952825 and 6529114.
900252 10-03 Rev. B
Solid State Electronics Center • www.magneticsensors.com • (800) 323-8295 • Page 7
