A1203LUA-T【PDF 8/14 页】IC SW CONTINUOUS TIME BIPO 3-SIP

收藏本站

您好，
买卖IC网欢迎您。
请登录
免费注册

买卖IC网

Sheet目录59

4页 5页 6页 7页 [8页]9页 10页 11页 12页

Continuous-Time Bipolar Switch Family

A1202

and A1203

Allegro MicroSystems, LLC

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

www.allegromicro.com

Functional Description

Bipolar Device Switching

The devices of the A120X family provide highly sensitive

switching for applications using magnetic fields of alternating

polarities, such as ring magnets. There are three switching modes

for bipolar devices, referred to as latch, unipolar switch, and

negative switch. Mode is determined by the switchpoint charac-

teristics of the individual device. The characteristic hysteresis,

HYS

, of the device, is the difference in the relative magnetic

strength and polarity of the switchpoints of the device. (Note

that, in the following descriptions, a negative magnetic value

indicates a north polarity field, and a positive magnetic value

indicates a south polarity field. For a given value of magnetic

strength, B

, the values B

and B

indicate two fields of equal

strength, but opposite polarity. B = 0 indicates the absence of a

magnetic field.)

Bipolar devices typically behave as latches. In this mode,

magnetic fields of opposite polarity and equivalent strengths

are needed to switch the output. When the magnetic fields are

removed (B ?0) the device remains in the same state until a

magnetic field of the opposite polarity and of sufficient strength

causes it to switch. The hysteresis of latch mode behavior is

shown in panel A of figure 1.

In contrast to latching, when a device exhibits unipolar switch-

ing, it only responds to a south magnetic field. The field must

be of sufficient strength, > B

, for the device to operate. When

the field is reduced beyond the B

level, the device switches

back to the high state, as shown in panel B of figure 1. Devices

exhibiting negative switch behavior operate in a similar but

opposite manner. A north polarity field of sufficient strength,

> B

, (more north than B

) is required for operation, although

the result is that V

OUT

switches high, as shown in panel C. When

Figure 1. Bipolar Device Output Switching Modes. These behaviors can be exhibited when using a circuit such as that shown in panel D. Panel A

displays the hysteresis when a device exhibits latch mode (note that the B

HYS

band incorporates B= 0), panel B shows unipolar switch behavior (the

HYS

band is more positive than B = 0), and panel C shows negative switch behavior (the B

HYS

band is more negative than B = 0). Bipolar devices,

such as the 120x family, can operate in any of the three modes.

HYS

OUT(SAT)

V+

HYS

OUT(SAT)

V+

HYS

OUT(SAT)

V+

B+

B 0

B+

(A)

(B)

(C)

VCC

Output

GND

VOUT

A120x

(D)

发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

*型号	*数量	厂商	批号	封装

添加更多采购

采购需求

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

我的联系方式