没有合适的资源？快使用搜索试试~ 我知道了~

文库首页开发技术硬件开发LP2997 DATASHEET

LP2997 DATASHEET

LP2997

PDF

DATASHEET

需积分: 0 2 下载量 21 浏览量 2012-12-07 14:56:22 上传评论收藏 1.07MB PDF 举报

温馨提示

试读

22页

DDR FPGA 原理图设计中经常用到的芯片，下载有用的。

资源详情

资源评论

资源推荐

LP2997

June 29, 2012

DDR-II Termination Regulator

General Description

The LP2997 linear regulator is designed to meet the JEDEC

SSTL-18 specifications for termination of DDR-II memory.

The device contains a high-speed operational amplifier to

provide excellent response to load transients. The output

stage prevents shoot through while delivering 500mA contin-

uous current and transient peaks up to 900mA in the appli-

cation as required for DDR-II SDRAM termination. The

LP2997 also incorporates a V

SENSE

pin to provide superior

load regulation and a V

REF

output as a reference for the

chipset and DIMMs.

An additional feature found on the LP2997 is an active low

shutdown (SD

) pin that provides Suspend To RAM (STR)

functionality. When SD is pulled low the V

output will tri-

state providing a high impedance output, but, V

REF

will remain

active. A power savings advantage can be obtained in this

mode through lower quiescent current.

Features

■

Source and sink current

■

Low output voltage offset

■

No external resistors required

■

Linear topology

■

Suspend to Ram (STR) functionality

■

Low external component count

■

Thermal Shutdown

■

Available in SO-8, PSOP-8 packages

Applications

■

DDR-II Termination Voltage

■

SSTL-18 Termination

Typical Application Circuit

20109418

LP2997 DDR-II Termination Regulator

Connection Diagrams

20109403

PSOP-8 Layout

20109404

SO-8 Layout

Pin Descriptions

SO-8 Pin or PSOP-8 Pin Name Function

1 GND Ground

2 SD Shutdown

3 VSENSE Feedback pin for regulating V

4 VREF Buffered internal reference voltage of V

DDQ

5 VDDQ Input for internal reference equal to V

DDQ

6 AVIN Analog input pin

7 PVIN Power input pin

8 VTT Output voltage for connection to termination resistors

EP Exposed pad thermal connection Connect to Ground

Ordering Information

Order Number Package Type NSC Package Drawing Supplied As

LP2997M SO-8 M08A 95 Units per Rail

LP2997MX SO-8 M08A 2500 Units Tape and Reel

LP2997MR PSOP-8 MRA08A 95 Units Tape and Reel

LP2997MRX PSOP-8 MRA08A 2500 Units Tape and Reel

www.ti.com 2

LP2997

Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,

please contact the Texas Instruments Sales Office/

Distributors for availability and specifications.

AVIN to GND −0.3V to +6V

PVIN to GND -0.3V to AVIN

VDDQ (Note 2) −0.3V to +6V

Storage Temp. Range −65°C to +150°C

Junction Temperature 150°C

Lead Temperature (Soldering, 10 sec) 260°C

SO-8 Thermal Resistance (θ

)

151°C/W

PSOP-8 Thermal Resistance (θ

)

43°C/W

Minimum ESD Rating (Note 3) 1kV

Operating Range

Junction Temp. Range (Note 4) 0°C to +125°C

AVIN to GND 2.2V to 5.5V

Electrical Characteristics Specifications with standard typeface are for T

= 25°C and limits in boldface type

apply over the full Operating Temperature Range (T

= 0°C to +125°C) (Note 5). Unless otherwise specified,

AVIN = 2.5V, PVIN = 1.8V, VDDQ = 1.8V.

Symbol Parameter Conditions Min Typ Max Units

REF

Voltage PVIN = VDDQ = 1.7V

PVIN = VDDQ = 1.8V

PVIN = VDDQ = 1.9V

0.837

0.887

0.936

0.860

0.910

0.959

0.887

0.937

0.986

VREF

REF

Output Impedance

REF

= -30 to +30 μA

2.5

kΩ

Output Voltage I

OUT

= 0A

PVIN = VDDQ = 1.7V

PVIN = VDDQ = 1.8V

PVIN = VDDQ = 1.9V

0.822

0.874

0.923

0.856

0.908

0.957

0.887

0.939

0.988

OUT

= ±0.5A (Note 8)

PVIN = VDDQ = 1.7V

PVIN = VDDQ = 1.8V

PVIN = VDDQ = 1.9V

0.828

0.878

0.928

0.856

0.908

0.957

0.890

0.940

0.990

Vos

Output Voltage Offset

REF

-V

)

OUT

= 0A

OUT

= -0.5A

OUT

= +0.5A

-25

Quiescent Current (Note 6) I

OUT

= 0A (Note 6) 320 500

µA

VDDQ

VDDQ Input Impedance 100

kΩ

Quiescent Current in

Shutdown (Note 6)

SD = 0V 115 150 µA

Q_SD

Shutdown Leakage Current SD = 0V 2 5 µA

Minimum Shutdown High

Level

1.9 V

Maximum Shutdown Low

Level

0.8 V

SENSE

Input Current 13 nA

Thermal Shutdown (Note 7) 165 Celsius

_HYS Thermal Shutdown

Hysteresis

10 Celsius

3 www.ti.com

LP2997

Note 1: Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating range indicates conditions for which the device is

intended to be functional, but does not guarantee specific performance limits. For guaranteed specifications and test conditions see Electrical Characteristics.

The guaranteed specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under

the listed test conditions.

Note 2: VDDQ voltage must be less than 2 x (AVIN - 1) or 6V, whichever is smaller.

Note 3: The human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin.

Note 4: At elevated temperatures, devices must be derated based on thermal resistance. The device in the SO-8 package must be derated at θ

= 151.2° C/W

junction to ambient with no heat sink.

Note 5: Limits are 100% production tested at 25°C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality

Control (SQC) methods. The limits are used to calculate National's Average Outgoing Quality Level (AOQL).

Note 6: Quiescent current defined as the current flow into AVIN.

Note 7: The maximum allowable power dissipation is a function of the maximum junction temperature, T

J(MAX)

, the junction to ambient thermal resistance, θ

and the ambient temperature, T

. Exceeding the maximum allowable power dissipation will cause excessive die temperature and the regulator will go into thermal

shutdown.

Note 8: V

load regulation is tested by using a 10 ms current pulse and measuring V

www.ti.com 4

LP2997

Typical Performance Characteristics

Iq vs AV

in SD

20109420

Iq vs AV

20109421

and V

20109422

REF

vs V

DDQ

20109424

vs V

DDQ

20109426

Iq vs AV

in SD Temperature

20109427

5 www.ti.com

LP2997

剩余21页未读，继续阅读

内容反馈

aqjinhu

粉丝: 0
资源: 2

上传资源快速赚钱

我的内容管理展开

我的资源快来上传第一个资源

我的收益

登录查看自己的收益

我的积分登录查看自己的积分

我的C币登录后查看C币余额

我的收藏

我的下载

下载帮助

前往需求广场，查看用户热搜

LP2997 DATASHEET

评论0

最新资源

LP2997 DATASHEET

评论0

LPDDR5_Specification.pdf

LPDDR5-JEDEC标准

JESD209-5 LPDDR5.pdf.rar

DRAM技术精解(中文) DDR3_DDR4_DDR5_LPDDR3_LPDDR4_LPDDR5.pdf

SMP8634 DATASHEET

AT89C51RE2 DATASHEET

IMX377CQT_DATASHEET

AP3216C DATASHEET

MT9M111 DATASHEET

HMC822LP4E Datasheet及电路图

LP2951 datasheet

LP2995(datasheet)

LP399_datasheet

OV9650 DATASHEET

CSR8610 DATASHEET

TK0212 DATASHEET

OV2643 DATASHEET

OV9734 DATASHEET

omap5912 datasheet

Datasheet_LP140WF1-SPU1.pdf_1413428147_lcddisplay_

MSP-exp430F5529 data sheet

iCE40™ LP/HX Family Data Sheet

高通MSM8916 datasheet

BMA220 DATASHEET

SI32171 DATASHEET

GC4663 DATASHEET

SSD2828 DATASHEET

FT232R DATASHEET

SC6600V Datasheet

最新资源