BR93L86-W Rohm Semiconductor, BR93L86-W Datasheet - Page 34

• Manufacturer Part Number: BR93L86-W
• Description: IC EEPROM 16KBIT 2MHZ 8DIP
• Manufacturer: Rohm Semiconductor

Specifications of BR93L86-W

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 16K (1K x 16)
• Speed: 2MHz
• Interface: Microwire, 3-Wire Serial
• Voltage - Supply: 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-DIP (0.300", 7.62mm)
• 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
4-2) Timing of CS = “H” after write command. DO terminal in READY / BUSY function output.
Feedback input at timing of these 4-1) and 4-2) does not cause disorder in basic operations, if resistance R is inserted.
○Selection of resistance value R
4-3) Address data A0 = “1” input, dummy bit “0” output timing
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. And insert resistance R, and set the value R to satisfy EEPROM input level VIH/VIL,
even under influence of voltage decline owing to leak current and so forth. Insertion of R will not cause any influence
upon basic operations.
(When microcontroller DI/O output is “H”, EEPROM DO outputs “L”, and “H” is input to DI)
・Make the through current to EEPROM 10mA or below.
・See to it that the input level VIH of EEPROM should satisfy the following.
When the next start bit input is recognized, “HIGH-Z” gets in.
→Especially, at command input after write, when CS input is started with microcontroller DI/O output “L”,
READY output “H” is output from DO terminal, and through current route occurs.
Fig.49 Circuit at DI, DO direct connection (Microcontroller DI/O “H” output, EEPROM “L” output)
Microcontroller
“H” output
EEPROM CS input
EEPROM SK input
EEPROM DI input
EEPROM DO output
Microcontroller DI/O port
DI/O PORT
VOHM
IOHM
Fig.48 Collision timing at DI, DO direct connection
VOLE
R
DO
DI
Write command
Write command
Write command
Write command
Write command
Microcontroller output
EEPROM
“L” output
BUSY
Microcontroller input
BUSY
～ ～
～ ～
～ ～
～ ～
～ ～
34/40
READY
READY
Microcontroller output
～ ～
～ ～
～ ～
～ ～
～ ～
Conditions
At this moment, if VOLE=0V,
READY
・VIHE
・VOLE
・VOHM
・IOHM
∴
Collision of DI input and DO output
VOHM ≦ VIHE
VOHM ≦ IOHM×R + VOLE
VOHM ≦ IOHM×R
High-Z
: EEPROM VIH specifications
: EEPROM VOL specifications
: Microcontroller VOH specifications
: Microcontroller IOH specifications
R ≧
VOHM
IOHM
・・・⑦
Technical Note
2011.02 - Rev.F