- 您现在的位置：买卖IC网 > PDF目录1900 > ADSP-21990BSTZ (Analog Devices Inc)IC DSP CONTROLLER 16BIT 176-LQFP PDF资料下载
参数资料
| 型号： | ADSP-21990BSTZ |
| 厂商： | Analog Devices Inc |
| 文件页数： | 36/50页 |
| 文件大小： | 0K |
| 描述： | IC DSP CONTROLLER 16BIT 176-LQFP |
| 产品变化通告： | Product Discontinuance 27/Oct/2011 |
| 标准包装： | 1 |
| 系列： | ADSP-21xx |
| 类型： | 定点 |
| 接口： | SPI，SSP |
| 时钟速率： | 160MHz |
| 非易失内存： | 外部 |
| 芯片上RAM： | 20kB |
| 电压 - 输入/输出： | 3.30V |
| 电压 - 核心： | 2.50V |
| 工作温度： | -40°C ~ 85°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 176-LQFP |
| 供应商设备封装： | 176-LQFP（24x24） |
| 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页当前第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
ADSP-21990
Rev. A
|
Page 41 of 50
|
August 2007
TEST CONDITIONS
The DSP is tested for output enable, disable, and hold time.
Output Disable Time
Output pins are considered to be disabled when they stop driv-
ing, go into a high impedance state, and start to decay from their
output high or low voltage. The time for the voltage on the bus
to decay by ΔV is dependent on the capacitive load, CL, and the
load current, IL. This decay time can be approximated by the fol-
lowing equation.
The output disable time tDIS is the difference between tMEASURED
val from when the reference signal switches to when the output
voltage decays ΔV from the measured output high or output low
voltage. The tDECAY is calculated with test loads CL and IL, and
with ΔV equal to 0.5 V.
Output Enable Time
Output pins are considered to be enabled when they have made
a transition from a high impedance state to when they start driv-
ing. The output enable time tENA is the interval from when a
reference signal reaches a high or low voltage level to when the
output has reached a specified high or low trip point, as shown
in the Output Enable/Disable diagram (Figure 19). If multiple
pins (such as the data bus) are enabled, the measurement value
is that of the first pin to start driving.
Example System Hold Time Calculation
To determine the data output hold time in a particular system,
on Page 41. Choose ΔV to be the difference between the
ADSP-21990 output voltage and the input threshold for the
device requiring the hold time. A typical ΔV will be 0.4 V. CL is
the total bus capacitance (per data line), and IL is the total leak-
age or three-state current (per data line). The hold time will be
tDECAY plus the minimum disable time (i.e., tDATRWH for the
write cycle).
Figure 19. Output Enable/Disable
Figure 20. Equivalent Device Loading for AC Measurements (Includes All
Fixtures)
t
DECAY
C
L
V
Δ
I
L
---------------
=
REFERENCE
SIGNAL
tDIS
OUTPUT STARTS
DRIVING
VOH (MEASURED) – V2.0V
VOL (MEASURED) + V1.0V
tMEASURED
VOH (MEASURED)
VOL (MEASURED)
HIGH IMPEDANCE STATE.
TEST CONDITIONS CAUSE THIS VOLTAGE
TO BE APPROXIMATELY 1.5V
OUTPUT STOPS
DRIVING
tDECAY
tENA
1.5V
50pF
TO
OUTPUT
PIN
IOL
IOH
Figure 21. Voltage Reference Levels for AC Measurements (Except Output
Enable/Disable)
INPUT
OR
OUTPUT
1.5V
相关PDF资料 |
PDF描述 |
|---|---|
| ADSP-21991BSTZ | IC DSP CONTROLLER 16BIT 176-LQFP |
| ADSP-21992YBC | IC DSP CTLR 16BIT 196CSPBGA |
| ADSP-3PARCBF548M01 | MODULE BOARD BF548 |
| ADSP-BF506KSWZ-4F | IC DSP 12BIT 400MHZ 120LQFP |
| ADSP-BF518BSWZ-4F4 | IC DSP 16/32B 400MHZ LP 176LQFP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| ADSP-21991BBC | 制造商:Analog Devices 功能描述:DSP Fixed-Point 16-Bit 150MHz 150MIPS 196-Pin Mini-BGA |
| ADSP-21991BBCZ | 功能描述:IC DSP CTLR 16BIT 196CSPBGA RoHS:是 类别:集成电路 (IC) >> 嵌入式 - DSP（数字式信号处理器） 系列:ADSP-21xx 标准包装:2 系列:StarCore 类型:SC140 内核 接口:DSI，以太网，RS-232 时钟速率:400MHz 非易失内存:外部 芯片上RAM:1.436MB 电压 - 输入/输出:3.30V 电压 - 核心:1.20V 工作温度:-40°C ~ 105°C 安装类型:表面贴装 封装/外壳:431-BFBGA，FCBGA 供应商设备封装:431-FCPBGA（20x20） 包装:托盘 |
| ADSP-21991BST | 制造商:Analog Devices 功能描述:DSP Fixed-Point 16-Bit 160MHz 160MIPS 176-Pin LQFP 制造商:Rochester Electronics LLC 功能描述:HIGH PERFORMANCE MIXED SIGNAL DSP - Bulk |
| ADSP-21991BSTZ | 功能描述:IC DSP CONTROLLER 16BIT 176-LQFP RoHS:是 类别:集成电路 (IC) >> 嵌入式 - DSP（数字式信号处理器） 系列:ADSP-21xx 标准包装:2 系列:StarCore 类型:SC140 内核 接口:DSI，以太网，RS-232 时钟速率:400MHz 非易失内存:外部 芯片上RAM:1.436MB 电压 - 输入/输出:3.30V 电压 - 核心:1.20V 工作温度:-40°C ~ 105°C 安装类型:表面贴装 封装/外壳:431-BFBGA，FCBGA 供应商设备封装:431-FCPBGA（20x20） 包装:托盘 |
| ADSP-21992BBC | 制造商:Analog Devices 功能描述:DSP Fixed-Point 16-Bit 150MHz 150MIPS 196-Pin CSP-BGA 制造商:Rochester Electronics LLC 功能描述:MIXED SIGNAL DSP W/32K DM RAM& 16K PMRAM - Bulk |
发布紧急采购，3分钟左右您将得到回复。