BU52069GWZ Datasheet, PDF (7/19 Pages) Rohm – Unipolar Detection Hall IC

BU52069GWZ
Description of Operations
Micropower Operation (Small Current Consumption Using Intermittent Sensing)
IDD
Period
Startup Time
Standby Time
The unipolar detection Hall IC uses intermittent sensing
save energy. At startup the Hall elements, amplifier,
comparator, and other detection circuits power on and
magnetic detection begins. During standby, the detection
circuits power off, thereby reducing current consumption.
The detection results are held while standby is active, and
then output.
Figure 12
t
Reference Period: 50ms (MAX100ms)
Reference Startup Time:24µs
(Offset Cancellation)
VDD
I
B_×
GND
Figure 13
+
Hall Voltage
-
The Hall elements form an equivalent Wheatstone (resistor)
bridge circuit. Offset voltage may be generated by a
differential in this bridge resistance, or can arise from
changes in resistance due to package or bonding stress. A
dynamic offset cancellation circuit is employed to cancel this
offset voltage.
When the Hall elements are connected as shown in Figure
13 and a magnetic field is applied perpendicular to the Hall
elements, a voltage is generated at the mid-point terminal of
the bridge. This is known as Hall voltage.
Dynamic cancellation switches the wiring (shown in the
figure) to redirect the current flow to a 90° angle from its
original path, and thereby cancels the Hall voltage.
The magnetic signal (only) is maintained in the sample/hold
circuit during the offset cancellation process and then
released.
www.rohm.com
© 2014 ROHM Co., Ltd. All rights reserved.
TSZ22111 • 15 • 001
7/15
TSZ02201-0M2M0F414040-1-2
7.Nov.2014 Rev.001