参数资料
| 型号： | XR16L2552IM-F |
| 厂商： | Exar Corporation |
| 文件页数： | 11/45页 |
| 文件大小： | 0K |
| 描述： | IC UART FIFO 16B DUAL 48TQFP |
| 标准包装： | 250 |
| 特点： | * |
| 通道数： | 2，DUART |
| FIFO's： | 16 字节 |
| 规程： | RS232 |
| 电源电压： | 2.25 V ~ 5.5 V |
| 带自动流量控制功能： | 是 |
| 带IrDA 编码器/解码器： | 是 |
| 带故障启动位检测功能： | 是 |
| 带调制解调器控制功能： | 是 |
| 带CMOS： | 是 |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 48-TQFP |
| 供应商设备封装： | 48-TQFP（7x7） |
| 包装： | 托盘 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页当前第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页
XR16L2552
19
REV. 1.1.2
2.25V TO 5.5V DUART WITH 16-BYTE FIFO
2.19
Sleep Mode with Auto Wake-Up
The L2552 supports low voltage system designs, hence, a sleep mode is included to reduce its power
consumption when the chip is not actively used.
All of these conditions must be satisfied for the L2552 to enter sleep mode:
■ no interrupts pending for both channels of the L2552 (ISR bit-0 = 1)
■ divisor is a non-zero value (ie. DLL = 0x1)
■ sleep mode of both channels are enabled (IER bit-4 = 1)
■ modem inputs are not toggling (MSR bits 0-3 = 0)
■ RX input pins are idling at a logic 1
The L2552 stops its crystal oscillator to conserve power in the sleep mode. User can check the XTAL2 pin for
no clock output as an indication that the device has entered the sleep mode.
The L2552 resumes normal operation by any of the following:
■ a receive data start bit transition (logic 1 to 0)
■ a data byte is loaded to the transmitter, THR or FIFO
■ a change of logic state on any of the modem or general purpose serial inputs: CTS#, DSR#, CD#, RI#
If the L2552 is awakened by any one of the above conditions, it will return to the sleep mode automatically after
all interrupting conditions have been serviced and cleared. If the L2552 is awakened by the modem inputs, a
read to the MSR is required to reset the modem inputs. In any case, the sleep mode will not be entered while
an interrupt is pending from channel A or B. The L2552 will stay in the sleep mode of operation until it is
disabled by setting IER bit-4 to a logic 0.
If the address lines, data bus lines, IOW#, IOR#, CSA#, CSB#, and modem input lines remain steady when the
L2552 is in sleep mode, the maximum current will be in the microamp range as specified in the DC Electrical
Characteristics on page 36. If the input lines are floating or are toggling while the L2552 is in sleep mode, the
current can be up to 100 times more. If any of those signals are toggling or floating, then an external buffer
would be required to keep the address, data and control lines steady to achieve the low current. As an
alternative, please refer to the XR16L2551 with the PowerSave feature that eliminates any unnecessary
external buffer.
A word of caution: owing to the starting up delay of the crystal oscillator after waking up from sleep mode, the
first few receive characters may be lost. The number of characters lost during the restart also depends on your
operating data rate. More characters are lost when operating at higher data rate. Also, it is important to keep
RX A/B inputs idling at logic 1 or “marking” condition during sleep mode to avoid receiving a “break” condition
upon the restart. This may occur when the external interface transceivers (RS-232, RS-485 or another type)
are also put to sleep mode and cannot maintain the “marking” condition. To avoid this, the designer can use a
47k-100k ohm pull-up resistor on the RXA and RXB pins.
相关PDF资料 |
PDF描述 |
|---|---|
| XR16L2550IL-F | IC UART FIFO 16B DUAL 32QFN |
| ST16C2552CJ44TR-F | IC UART FIFO 16B DUAL 44PLCC |
| ST78C36CJ44-F | IC UART FIFO 16B 44PLCC |
| ST16C580CQ48-F | IC UART FIFO 16B 48TQFP |
| XR88C92CVTR-F | IC UART FIFO DUAL 44LQFP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| XR16L2552IMTR-F | 制造商:Exar Corporation 功能描述:UART 2-CH 16Byte FIFO 2.5V/3.3V/5V 48-Pin TQFP T/R 制造商:Exar Corporation 功能描述:XR16L2552IMTR-F |
| XR16L2750 | 制造商:EXAR 制造商全称:EXAR 功能描述:2.25V TO 5.5V DUART WITH 64-BYTE FIFO |
| XR16L2750_05 | 制造商:EXAR 制造商全称:EXAR 功能描述:2.25V TO 5.5V DUART WITH 64-BYTE FIFO |
| XR16L2750CJ | 制造商:EXAR 制造商全称:EXAR 功能描述:2.25V TO 5.5V DUART WITH 64-BYTE FIFO |
| XR16L2750CJ-0A-EB | 功能描述:UART 接口集成电路 Supports L2750 44 ld PLCC, ISA Interface RoHS:否 制造商:Texas Instruments 通道数量:2 数据速率:3 Mbps 电源电压-最大:3.6 V 电源电压-最小:2.7 V 电源电流:20 mA 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:LQFP-48 封装:Reel |
发布紧急采购，3分钟左右您将得到回复。