BU21051FS-E2 Rohm Semiconductor, BU21051FS-E2 Datasheet - Page 5

• Manufacturer Part Number: BU21051FS-E2
• Description: IC CAP SENSOR SWITCH 8CH 16-SSOP
• Manufacturer: Rohm Semiconductor
• Type: Capacitive Switchr

Specifications of BU21051FS-E2

• Input Type: Logic
• Output Type: Logic
• Interface: Port
• Current - Supply: 500µA
• Mounting Type: Surface Mount
• Package / Case: 16-SSOP
• Supply Voltage: 5 V
• Number Of Channels: 2
• Dimensions: 6.6 mm L x 6.2 mm W x 1.5 mm H
• Output Voltage: 5.5 V
• Power Dissipation: 500 mW
• Temperature Range: - 55 C to + 125 C
• Termination Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: BU21051FS-E2TR

●Setting method
●Operation Mode
●Power Supply ON Sequence
© 2009 ROHM Co., Ltd. All rights reserved.
BU21051FS
www.rohm.com
【Filter selection】
The noise filter effect can be selected If “Strong” is selected, noise will get down, but the reaction time will be longer.
1)Please for the first time in a minimum gain.
2)THOFF = 0V, and, THON 1/2VDD voltage as a guideline for whether or not to switch ON, and gain selection to please the rough.
This IC has several modes, called detection mode, calibration mode, and shut-down mode. Each mode
is described as follow
【Detection Mode】
【Calibration Mode】
【Shutdown Mode】
This IC has two power input pins AVDD and DVDD. Power ON sequence must be whether set DVDD first
or set the two at one time. Since internal reset circuit is monitoring AVDD, wrong power ON sequence
may cause initialization error.
Note: ON gain to a minimum, you gain more precision amended to increase the impact too, so please take note.
This is normal operation mode of this IC. In this mode, IC detects the sensor capacitance continually.
Under detection mode when no operation has been detected for sometime, Sensor offset calibration will be done.
And the interval between each calibration is fixed
Detection mode and Calibration mode are switched automatically.
When SDN pin is set to “L”, IC will be shut-down and all internal circuits will stop working.
IC will work again when SDN pin is set to “H”.
Sensor ON threshold
FILTER = ” L ” : filter effect → under
delay time → small
FILTER =”L”: filter effect
5/6
delay time
→
→
strong
big
Switch detect time
Technical Note
2009.04 - Rev.B