参数资料
型号: BR24L04F-WE2
厂商: Rohm Semiconductor
文件页数: 35/41页
文件大小: 0K
描述: IC EEPROM 4KBIT 400KHZ 8SOP
标准包装: 1
格式 - 存储器: EEPROMs - 串行
存储器类型: EEPROM
存储容量: 4K (512 x 8)
速度: 400kHz
接口: I²C,2 线串口
电源电压: 1.8 V ~ 5.5 V
工作温度: -40°C ~ 85°C
封装/外壳: 8-SOIC(0.173",4.40mm 宽)
供应商设备封装: 8-SOP
包装: 标准包装
产品目录页面: 1379 (CN2011-ZH PDF)
其它名称: BR24L04F-WE2DKR
BR24L □□ -W Series,BR24S □□□ -W Series
Technical Note
In I C BUS, it is recommended that SDA port is of open drain input/output. However, when to use CMOS input / output of
● Cautions on microcontroller connection
Rs
2
tri state to SDA port, insert a series resistance Rs between the pull up resistance Rpu and the SDA terminal of EEPROM.
This is controls over current that occurs when PMOS of the microcontroller and NMOS of EEPROM are turned ON
simultaneously. Rs also plays the role of protection of SDA terminal against surge. Therefore, even when SDA port is
open drain input/output, Rs can be used.
ACK
SCL
R PU
R S
SDA
'H' output of microcontroller
'L' output of EEPROM
Microcontre
EEPROM
Over current flows to SDA line by 'H' output of
microcontroller and 'L' output of EEPROM.
Fig.50 I/O circuit diagram
Fig.51 Input/output collision timing
○ Maximum value of Rs
The maximum value of Rs is determined by following relations.
(1)SDA rise time to be determined by the capacity (CBUS) of bus line of Rpu and SDA shoulder be tR or below.
And AC timing should be satisfied even when SDA rise time is late.
(2)The bus electric potential A to be determined by Rpu and Rs the moment when EEPROM outputs 'L' to SDA bus should
sufficiently secure the input 'L' level (V IL ) of microcontroller including recommended noise margin 0.1Vcc.
V CC
R PU
A
(V CC - V OL )×R S
R PU +R S
+
V OL +0.1V CC ≦ V IL
R S
I OL
V OL
R S
V IL - V OL - 0.1V CC
1.1V CC - V IL
×
R PU
Bus line
Example ) When V CC =3V, V IL =0.3V CC , V OL =0.4V,
R PU =20k ?
V IL
capacity CBUS
Microcontroller
EEPROM
from(2),
R S
0.3×3 - 0.4 - 0.1×3
1.1×3 - 0.3×3
1.67 [ k ? ]
×
20×10 3
Fig.52 I/O circuit diagram
○ Maximum value of Rs
The minimum value of Rs is determined by over current at bus collision. When over current flows, noises in power source
line, and instantaneous power failure of power source may occur. When allowable over current is defined as I, the
following relation must be satisfied. Determine the allowable current in consideration of impedance of power source line
in set and so forth. Set the over current to EEPROM 10mA or below.
R PU
R S
'L' output
V CC
RS
RS
I
V CC
I
Over current Ⅰ
Example ) When V CC =3V, I=10mA
'H' output
Microcontroller
EEPROM
RS
3
10×10-3
Fig.53 I/O circuit diagram
www.rohm.com
? 2009 ROHM Co., Ltd. All rights reserved.
35/40
2009.09 - Rev.D
相关PDF资料
PDF描述
BR93L76RF-WE2 IC EEPROM 8KBIT 2MHZ 8SOP
BR24S16FJ-WE2 IC EEPROM 16KBIT 400KHZ 8SOP
BR93L56RFVJ-WE2 IC EEPROM 2KBIT 2MHZ 8-TSSOP
BR93L56RFVT-WE2 IC EEPROM 2KBIT 2MHZ 8-TSSOP
ASM36DRTF CONN EDGECARD 72POS DIP .156 SLD
相关代理商/技术参数
参数描述
BR24L04F-WTR 制造商:ROHM 制造商全称:Rohm 功能描述:High Reliability Series EEPROMs I2C BUS
BR24L04NUX-WE2 制造商:ROHM 制造商全称:Rohm 功能描述:High Reliability Series EEPROMs I2C BUS
BR24L04NUX-WTR 功能描述:IC EEPROM 4KBIT 100KHZ VSON8 RoHS:是 类别:集成电路 (IC) >> 存储器 系列:- 标准包装:2,000 系列:- 格式 - 存储器:RAM 存储器类型:SRAM - 异步 存储容量:256K (32K x 8) 速度:15ns 接口:并联 电源电压:3 V ~ 3.6 V 工作温度:-40°C ~ 85°C 封装/外壳:28-TSSOP(0.465",11.8mm 宽) 供应商设备封装:28-TSOP 包装:带卷 (TR) 其它名称:71V256SA15PZGI8
BR24L04-W 功能描述:IC EEPROM 4KBIT 400KHZ 8DIP RoHS:是 类别:集成电路 (IC) >> 存储器 系列:- 标准包装:1 系列:- 格式 - 存储器:EEPROMs - 串行 存储器类型:EEPROM 存储容量:16K (1K x 16) 速度:2MHz 接口:Microwire 3 线串行 电源电压:1.8 V ~ 5.5 V 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC(0.154",3.90mm 宽) 供应商设备封装:8-SOP-J 包装:Digi-Reel® 产品目录页面:1380 (CN2011-ZH PDF) 其它名称:BR93L86FJ-WE2DKR
BR24L08 制造商:未知厂家 制造商全称:未知厂家 功能描述:EEPROM