参数资料
| 型号： | KSZ8864RMNI |
| 厂商： | Micrel Inc |
| 文件页数： | 10/111页 |
| 文件大小： | 0K |
| 描述： | IC ETHERNET SWITCH 4PORT 64QFN |
| 特色产品： | KSZ8864RMN Ethernet Switches |
| 标准包装： | 348 |
| 系列： | * |
| 其它名称： | 576-3995 |
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页当前第10页第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页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页第104页第105页第106页第107页第108页第109页第110页第111页
1997 Microchip Technology Inc.
DS30444E - page 107
PIC16C9XX
14.4
Power-on Reset (POR), Power-up
Timer (PWRT) and Oscillator Start-up
Timer (OST)
14.4.1
POWER-ON RESET (POR)
A Power-on Reset pulse is generated on-chip when
VDD rise is detected (in the range of 1.5V - 2.1V). To
take advantage of the POR, just tie the MCLR pin
directly (or through a resistor) to VDD. This will elimi-
nate external RC components usually needed to create
a Power-on Reset. A maximum rise time for VDD is
specied. See Electrical Specications for details.
When the device starts normal operation (exits the
reset condition), device operating parameters (voltage,
frequency, temperature, ...) must be met to ensure
operation. If these conditions are not met, the device
must be held in reset until the operating conditions are
met.
For additional information, refer to Application Note
AN607, “
Power-up Trouble Shooting.”
14.4.2
POWER-UP TIMER (PWRT)
The Power-up Timer provides a xed 72 ms nominal
time-out on power-up only, from the POR. The
Power-up Timer operates on an internal RC oscillator.
The chip is kept in reset as long as the PWRT is active.
The PWRT’s time delay allows VDD to rise to an accept-
able level. A conguration bit is provided to enable/dis-
able the PWRT.
The power-up time delay will vary from chip to chip due
to VDD, temperature, and process variation. See DC
parameters for details.
14.4.3
OSCILLATOR START-UP TIMER (OST)
The Oscillator Start-up Timer (OST) provides 1024
oscillator cycle (from OSC1 input) delay after the
PWRT delay is over. This ensures that the crystal oscil-
lator or resonator has started and stabilized.
The OST time-out is invoked only for XT, LP and HS
modes and only on Power-on Reset or wake-up from
SLEEP.
14.4.4
TIME-OUT SEQUENCE
On power-up the time-out sequence is as follows: First
PWRT time-out is invoked after the POR time delay has
expired. Then OST is activated. The total time-out will
vary based on oscillator conguration and the status of
the PWRT. For example, in RC mode with the PWRT
disabled, there will be no time-out at all. Figure 14-8,
and
depict
time-out
sequences on power-up.
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the time-outs will expire. Then
bringing MCLR high will begin execution immediately
(Figure 14-9). This is useful for testing purposes or to
synchronize more than one PIC16CXXX device operat-
ing in parallel.
Table 14-5 shows the reset conditions for some special
function registers, while Table 14-6 shows the reset
conditions for all the registers.
14.4.5
POWER CONTROL/STATUS REGISTER
(PCON)
Bit1 is Power-on Reset Status bit POR. It is cleared on
a Power-on Reset and unaffected otherwise. The user
must set this bit following a Power-on Reset.
TABLE 14-3: TIME-OUT IN VARIOUS SITUATIONS
Oscillator Conguration
Power-up
Wake-up from SLEEP
PWRTE = 1
PWRTE = 0
XT, HS, LP
1024TOSC
72 ms + 1024TOSC
1024 TOSC
RC
—
72 ms
—
相关PDF资料 |
PDF描述 |
|---|---|
| KSZ8873FLLI | IC ETHERNET SWITCH 3PORT 64LQFP |
| KSZ8873MLLJ | IC ETHERNET SWITCH 3PORT 64LQFP |
| KSZ8873MMLI | IC ETHERNET SWITCH 3PORT 64LQFP |
| KSZ8893FQL | IC SWITCH FAST ETH 3PORT 128PQFP |
| KSZ8895MQI | IC ETHERNET SWITCH 5PORT 128PQFP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| KSZ8864RMNU | 功能描述:以太网 IC 4-Port 10/100BT Switch with MII/RMII (Automotive) RoHS:否 制造商:Micrel 产品:Ethernet Switches 收发器数量:2 数据速率:10 Mb/s, 100 Mb/s 电源电压-最大:1.25 V, 3.45 V 电源电压-最小:1.15 V, 3.15 V 最大工作温度:+ 85 C 封装 / 箱体:QFN-64 封装:Tray |
| KSZ8864RMNU TR | 制造商:Micrel Inc 功能描述:IC ETHERNET SWITCH 4PORT 64MLF |
| KSZ8873FLL | 功能描述:以太网 IC 3-Port Fast Ethernet Switch with 2x FX Ports - Lead free RoHS:否 制造商:Micrel 产品:Ethernet Switches 收发器数量:2 数据速率:10 Mb/s, 100 Mb/s 电源电压-最大:1.25 V, 3.45 V 电源电压-最小:1.15 V, 3.15 V 最大工作温度:+ 85 C 封装 / 箱体:QFN-64 封装:Tray |
| KSZ8873FLL-EVAL | 功能描述:以太网开发工具 3-Port Fast Ethernet Switch with 2x FX Ports - Evaluation Board RoHS:否 制造商:Micrel 产品:Evaluation Boards 类型:Ethernet Transceivers 工具用于评估:KSZ8873RLL 接口类型:RMII 工作电源电压: |
| KSZ8873FLLI | 功能描述:以太网 IC 3-Port Fast Ethernet Switch with 2x FX Ports (Industrial Grade) RoHS:否 制造商:Micrel 产品:Ethernet Switches 收发器数量:2 数据速率:10 Mb/s, 100 Mb/s 电源电压-最大:1.25 V, 3.45 V 电源电压-最小:1.15 V, 3.15 V 最大工作温度:+ 85 C 封装 / 箱体:QFN-64 封装:Tray |
发布紧急采购，3分钟左右您将得到回复。