BR93L66RF-WE2 Rohm Semiconductor, BR93L66RF-WE2 Datasheet - Page 17

• Manufacturer Part Number: BR93L66RF-WE2
• Description: IC EEPROM 4KBIT 2MHZ 8SOP
• Manufacturer: Rohm Semiconductor

Specifications of BR93L66RF-WE2

• Memory Size: 4K (256 x 16)
• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Speed: 2MHz
• Interface: Microwire, 3-Wire Serial
• Voltage - Supply: 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOP
• Clock Frequency: 2MHz
• Supply Voltage Range: 1.8V To 5.5V
• Memory Case Style: SOP
• No. Of Pins: 8
• Operating Temperature Range: -40°C To +85°C
• Svhc: No SVHC (18-Jun-2010)
• Package /: RoHS Compliant
• Memory Configuration: 256 X 16
• Interface Type: Serial, Microwire
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

© 2011 ROHM Co., Ltd. All rights reserved.
BR93L□□-W Series, 93A□□-WM Series, BR93H□□-WC Series
www.rohm.com
5) READY / BUSY status display (DO terminal)
*Do not input any command while status signal is output. Command input in BUSY area is cancelled, but command input in READY area is accepted.
Therefore, status READY output is cancelled, and malfunction and mistake write may be made.
（DO status）
○Pull up resistance Rpu and pull down resistance Rpd of DO pin
Microcontroller
(common to BR93L46-W/A46-WM,BR93L56-W/A56-WM, BR93L66-W/A66-WM, BR93L76-W/A76-WM, BR93L86-W/A86-WM)
This display outputs the internal status signal. When CS is started after tCS (Min.200ns)
from CS fall after write command input, “H” or “L” is output.
R/B display＝“L” (BUSY) = write under execution
R/B display = “H” (READY) = command wait status
（DO status）
Microcontroller
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.
“L” input
“H” input
Fig.78 DO pull down resistance
VILM
VIHM
Fig.77 DO pull up resistance
After the timer circuit in the IC works and creates the period of tE/W, this time circuit completes automatically.
And write to the memory cell is made in the period of tE/W, and during this period, other command is not accepted.
Even after tE/W (max.5ms) from write of the memory cell, the following command is accepted.
Therefore, CS=“H” in the period of tE/W, and when input is in SK, DI, malfunction may occur, therefore, DI=“L” in the area
CS=“H”. (Especially, in the case of shared input port, attention is required.)
Rpu
Rpd
CS
SK
DI
DO
High-Z
IOLE
IOHE
WRITE
INSTRUCTION
CLOCK
Fig.79 R/B status output timing chart
VOLE
VOHE
“H” output
“L” output
EEPROM
EEPROM
t
SV
BUSY
STATUS
17/40
Example) When V
With the value of Rpu to satisfy the above equation, VOLE becomes 0.4V
or below, and with VILM(=0.8V), the equation ④ is also satisfied.
With the value of Rpd to satisfy the above equation, VOHE becomes 2.4V
or below, and with VIHM (=3.5V), the equation ⑥ is also satisfied.
READY
Example) When V
∴
∴
・VOLE
・IOLE
・VILM
・VOHE
・IOHE
・VIHM
from the equation ③,
VOHE ≧ VIHM
VIHM=Vcc×0.7V from the equation ⑤,
VOLE ≦ VILM
Rpu ≧
Rpu ≧
Rpu ≧ 2.2 [kΩ]
Rpd ≧
Rpd ≧
Rpd ≧ 48 [kΩ]
CC
=5V, VOLE=0.4V, IOLE=2.1mA, VILM=0.8V,
: EEPROM VOL specifications
: EEPROM IOL specifications
: Microcontroller VIL specifications
: EEPROM VOH specifications
: EEPROM IOH specifications
: Microcontroller VIH specifications
CC
Vcc－VOLE
=5V, VOHE=Vcc－0.2V, IOHE=0.1mA,
2.1×10
0.1×10
VOHE
IOHE
IOLE
5－0.4
5－0.2
-3
-3
・・・③
・・・④
・・・⑤
・・・⑥
Technical Note
2011.02 - Rev.F