BU9891GUL-W Rohm, BU9891GUL-W Datasheet
BU9891GUL-W
Related parts for BU9891GUL-W
BU9891GUL-W Summary of contents
Page 1
... WL-CSP EEPROM family Microwire Bus BU9891GUL-W ●Description BU9891GUL-W is serial EEPROM of serial 3-line interface method ●Features 1) 3-line communications of chip select, serial clock, serial data input / output (the case where input and output are shared) 2) Actions available at high speed 2MHz clock (2.5~5.5V) 3) Speed write available (write time 5ms max ...
Page 2
... BU9891GUL-W ●Recommended action conditions Parameter Symbol Power source voltage Input voltage ●Memory cell characteristics (VCC=1.7~5.5V) Parameter *1 Number of data rewrite times *1 Data hold years ○Shipment data all address FFFFh *1 Not 100% TESTED ●Electrical characteristics (Unless otherwise specified, VCC=1.7~5.5V, Ta=-40~+85℃) Parameter Symbol “L” input voltage 1 “ ...
Page 3
... BU9891GUL-W ●Action timing characteristics (Ta=-40~+85℃, VCC=2.5~5.5V) Parameter SK frequency SK “H” time SK “L” time CS “L” time CS setup time DI setup time CS hold time DI hold time Data “1” output delay time Data “0” output delay time Time from CS to output establishment ...
Page 4
... BU9891GUL-W ●BU9891GUL-W Characteristic data (The following characteristic data are Typ. values.) 6 Ta=-40℃ 5 Ta=25℃ Ta=85℃ 4 SPEC VCC[V] Fig.2 H input voltage VIL(CS,SK,DI) 1 Ta=-40℃ Ta=25℃ 0.8 Ta=85℃ 0.6 0.4 SPEC 0 IOL[mA] Fig.5 L output voltage VOL-IOL(Vcc=2.5V) 5 Ta=-40℃ Ta=25℃ 4 Ta=85℃ ...
Page 5
... BU9891GUL-W ● BU9891GUL-W Characteristic data (The following characteristic data are Typ. values.) 5 fSK=500kHz DATA=0000h 4 SPEC 3 Ta=-40℃ Ta=25℃ 2 Ta=85℃ VCC[V] Fig.14 Current consumption at WRITE action 100 10 SPEC 1 SPEC Ta=-40℃ Ta=25℃ 0.1 Ta=85℃ 0. VCC[V] Fig.17 SK frequency fSK 1.2 Ta=-40℃ ...
Page 6
... BU9891GUL-W ●BU9891GUL-W Characteristic data (The following characteristic data are Typ. values.) 1 Ta=-40℃ Ta=25℃ 0.8 Ta=85℃ SPEC 0.6 0.4 SPEC 0 VCC[V] Fig.26 Output data “1” delay time tPD1 6 SPEC Ta=-40℃ 2 Ta=25℃ Ta=85℃ VCC[V] Fig.29 Write cycle time tE/W www.rohm.com © ...
Page 7
... BU9891GUL-W ●Block diagram Command decode CS Control SK Clock generation Command DI register DO Dummy bit ●Pin assignment and function Land No. Pin Name Vcc GND B3 CS www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. Power source voltage detection Write prohibition Address 8bit ...
Page 8
... When the read and the write all commands are executed, data written in the selected memory cell is automatically deleted, and input data is written. www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. controller BU9891GUL-W Micro- controller ...
Page 9
... BU9891GUL-W ●Timing chart 1) Read cycle (READ High-Z *1 Start bit When data “1” is input for the first time after the rise of CS, this is recognized as a start bit. And when “1” is input after plural “0” are input recognized as a start bit, and the following operation is started. This is common to all the commands to described hereafter. ○ ...
Page 10
... BU9891GUL-W ●Application 1) Method to cancel each command ○READ Start bit Ope code 1bit 2bit Cancel is available in all areas in read mode. ・Method to cancel：cancel by CS=“L” Fig.36 READ cancel available timing ○WRITE Start bit Ope code 1bit 2bit 1 a：From start bit to 27 clock rise ＊ ...
Page 11
... BU9891GUL-W 3) Equivalent circuit Output circuit OEint. Fig.40 Output circuit (DO) Input circuit CS int. DI Fig.42 Input circuit (DI) 4) I/O peripheral circuit 4-1) Pull down CS. By making CS=“L” at power ON/OFF, mistake in operation and mistake write are prevented. ○Pull down resistance Rpd of CS pin To prevent mistake in operation and mistake write at power ON/OFF, CS pull down resistance is necessary. Select an appropriate value to this resistance value from microcontroller VOH, IOH, and VIL characteristics of this IC ...
Page 12
... BU9891GUL-W ○Pull up resistance Rpu and pull down resistance Rpd of DO pin As for pull up and pull down resistance value, select an appropriate value to this resistance value from microcontroller VIH, VIL, and VOH, IOH, VOL, IOL characteristics of this IC. Microcontroller Rpu IOLE VILM “L” input Fig ...
Page 13
... BU9891GUL-W 6) When to directly connect DI and DO This IC has independent input terminal DI and output terminal DO, and separate signals are handled on timing chart, meanwhile, by inserting a resistance R between these DI and DO terminals possible to carry out control by 1 control line. ○Data collision of microcontroller DI/O output and DO output and feedback of DO output to DI input. ...
Page 14
... BU9891GUL-W ○Selection of resistance value R The resistance R becomes through current limit resistance at data collision. When through current flows, noises of power source line and instantaneous stop of power source may occur. When allowable through current is defined as I, the following relation should be satisfied. Determine allowable current amount in consideration of impedance and so forth of power source line in set ...
Page 15
... BU9891GUL-W 7) Notes on power ON/OFF ・At power ON/OFF, set CS “L”. When CS is “H”, this IC gets in input accept status (active). If power is turned on in this status, noises and the likes may cause malfunction, mistake write or so. To prevent these, at power ON, set CS “L”. (When “L” status, all inputs are cancelled.) And at power decline, owing to power line capacity and so forth, low power status may continue long. At this case too, owing to the same reason, malfunction, mistake write may occur, therefore, at power OFF too, set CS “ ...
Page 16
... BU9891GUL-W ●Notes for use (1) Described numeric values and data are design representative values, and the values are not guaranteed. (2) We believe that application circuit examples are recommendable, however, in actual use, confirm characteristics further sufficiently. In the case of use by changing the fixed number of external parts, make your decision with sufficient margin in consideration of static characteristics and transition characteristics and fluctuations of external parts and our LSI ...
Page 17
... BU9891GUL-W ●Ordering part number Part No. Part No. VCSP50L1 (BU9891GUL-W) 1PIN MARK 1.60±0.05 0. φ 0.15)INDEX POST 6- φ 0.25±0.05 0. 0.3±0.05 P=0.5×2 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved Package W-CELL GUL : VCSP50L1 <Tape and Reel information> ...
Page 18
... ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing ...