REV. 2.3.1 2.97V TO 5.5V UART WITH 128-BYTE FIFO 23 2.21 Sleep Mode with Auto Wake-Up The 850 supports low voltage sy" />
參數(shù)資料
型號: XR16C850IMTR-F
廠商: Exar Corporation
文件頁數(shù): 16/56頁
文件大?。?/td> 0K
描述: IC UART FIFO 128B 48TQFP
標準包裝: 1,500
特點: *
通道數(shù): 1,UART
FIFO's: 128 字節(jié)
規(guī)程: RS485
電源電壓: 2.97 V ~ 5.5 V
帶自動流量控制功能:
帶IrDA 編碼器/解碼器:
帶故障啟動位檢測功能:
帶調(diào)制解調(diào)器控制功能:
帶CMOS:
安裝類型: 表面貼裝
封裝/外殼: 48-TQFP
供應(yīng)商設(shè)備封裝: 48-TQFP(7x7)
包裝: 帶卷 (TR)
xr
XR16C850
REV. 2.3.1
2.97V TO 5.5V UART WITH 128-BYTE FIFO
23
2.21
Sleep Mode with Auto Wake-Up
The 850 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 850 to enter sleep mode:
no interrupts pending for the 850 (ISR bit-0 = 1)
sleep mode is enabled (IER bit-4 = 1)
modem inputs are not toggling (MSR bits 0-3 = 0)
RX input pin is idling at a logic 1
The 850 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 850 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 850 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 850 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. The 850 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
850 is in sleep mode, the maximum current will be in the microamp range as specified in the DC Electrical
Characteristics on page 42. If the input lines are floating or are toggling while the 850 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.
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. Also, make sure the RX input is idling at logic 1 or “marking” condition
during sleep mode. This may not 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 system design
engineer can use a 47k ohm pull-up resistor on the RX input.
相關(guān)PDF資料
PDF描述
XR16C854IQ-F IC UART FIFO 128B QUAD 100QFP
XR16C864IQ-F IC UART FIFO 128B QUAD 100QFP
XR16L2450IJ-F IC UART FIFO 1B DUAL 44PLCC
XR16L2550IJ-F IC UART FIFO 16B DUAL 44PLCC
XR16L2551IM-F IC UART FIFO 16B DUAL 48TQFP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
XR16C850IP 制造商:未知廠家 制造商全稱:未知廠家 功能描述:UART|CMOS|DIP|40PIN|PLASTIC
XR16C850IQ 制造商:未知廠家 制造商全稱:未知廠家 功能描述:UART|CMOS|QFP|52PIN|PLASTIC
XR16C854 制造商:EXAR 制造商全稱:EXAR 功能描述:并轉(zhuǎn)串4串口擴展芯片
XR16C854CJ 制造商:Rochester Electronics LLC 功能描述: 制造商:Exar Corporation 功能描述:
XR16C854CJ-0A-EVB 功能描述:UART 接口集成電路 Supports C854 68 ld PLCC, ISA Interface RoHS:否 制造商:Texas Instruments 通道數(shù)量:2 數(shù)據(jù)速率:3 Mbps 電源電壓-最大:3.6 V 電源電壓-最小:2.7 V 電源電流:20 mA 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:LQFP-48 封裝:Reel