参数资料
型号: A4954ELPTR-T
厂商: Allegro Microsystems Inc
文件页数: 5/9页
文件大小: 0K
描述: IC PWM MOTOR DVR DUAL 16-ETSSOP
特色产品: A4952, A4953, and A4954 Full Bridge Motor Drivers
标准包装: 1
应用: PWM 电机驱动器
评估套件: 可供
输出数: 2
电流 - 输出: 1.5A
电源电压: 8 V ~ 40 V
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 16-TSSOP(0.173",4.40mm)裸露焊盘
供应商设备封装: 16-EPAD TSSOP
包装: 标准包装
配用: 620-1427-ND - BOARD EVAL MOTOR CONTROL A4954
其它名称: 620-1384-6
A4954
Device Operation
Functional Description
Dual Full-Bridge DMOS
PWM Motor Driver
I TripMAX =
TheA4954 is designed to operate two DC motors.The output
drivers are all low-R DS(on) , N-channel DMOS drivers that feature
internal synchronous rectification to reduce power dissipation.
The current in each of the two output full bridges is regulated
with fixed off-time pulse width modulated (PWM) control cir-
cuitry. The IN1-IN2 and IN3-IN4 inputs allow two-wire control
for each bridge.
Protection circuitry includes internal thermal shutdown, and pro-
tection against shorted loads, or against output shorts to ground
or supply. Undervoltage lockout prevents damage by keeping the
outputs off until the driver has enough voltage to operate nor-
mally.
Standby Mode
Low Power Standby mode is activated when all four input (INx)
pins are low for longer than 1 ms. Low Power Standby mode
disables most of the internal circuitry, including the charge pump
and the regulator. When the A4954 is coming out of standby
mode, the charge pump should be allowed to reach its regulated
voltage (a maximum delay of 200 μ s) before any PWM com-
mands are issued to the device.
Internal PWM Current Control
Initially, a diagonal pair of source and sink FET outputs are
enabled and current flows through the motor winding and the
optional external current sense resistor, R Sx . When the voltage
across R Sx equals the comparator trip value, then the current
sense comparator resets the PWM latch. The latch then turns off
the sink and source FETs (Mixed Decay mode).
V REF
The maximum value of current limiting is set by the selection
of R Sx and the voltage at the VREFx pin in each channel. The
transconductance function is approximated by the maximum
value of current limiting, I TripMAX (A), which is set by:
V REF
A V R S
where V REF is the input voltage on the VREFx pin (V) and R S is
the resistance of the sense resistor ( Ω ) on the corresponding LSSx
terminal.
Overcurrent Protection
A current monitor will protect the IC from damage due to output
shorts. If a short is detected, the IC will latch the fault and dis-
able the outputs. Each channel has independent OCP protection.
The fault latch can only be cleared by coming out of Low Power
Standby mode or by cycling the power to VBB. During OCP
events, Absolute Maximum Ratings may be exceeded for a short
period of time before the device latches.
Shutdown
If the die temperature increases to approximately 160°C, the full
bridge outputs will be disabled until the internal temperature falls
below a hysteresis, T TSDhys , of 15°C. Internal UVLO is present
on VBB to prevent the output drivers from turning-on below the
UVLO threshold.
Braking
The braking function is implemented by driving the device in
Slow Decay mode, which is done by applying a logic high to both
inputs of both channels, after a bridge-enable Chop command
(see PWM Control Truth Table). Because it is possible to drive
current in both directions through the DMOS switches, this con-
figuration effectively shorts-out the motor-generated BEMF, as
long as the Chop command is asserted. The maximum current can
be approximated by V BEMF / R L . Care should be taken to ensure
that the maximum ratings of the device are not exceeded in worse
case braking situations: high speed and high-inertia loads.
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
相关PDF资料
PDF描述
A4960KJPTR-T IC BLDC CTLR BRUSHLESS 32LQFP
A4970SLBTR-T IC PWM MOTOR DVR FULL 24-SOICW
A4973SLBTR-T IC PWM MOTOR DVR FULL 16SOIC
A4975SB-T IC PWM MICROSTEP DVR FULL 16DIP
A4979GLPTR-T IC MOTOR DRVR MICRO STEP 28TSSOP
相关代理商/技术参数
参数描述
A4955GESTR-T 功能描述:Motor Driver NMOS Parallel 20-QFN-EP (4x4) 制造商:allegro microsystems, llc 系列:- 包装:剪切带(CT) 零件状态:有效 电机类型 - 步进:- 电机类型 - AC,DC:有刷直流 功能:控制器 - 换向,方向管理 输出配置:前置驱动器 - 半桥(2) 接口:并联 技术:NMOS 步进分辨率:- 应用:通用 电流 - 输出:- 电压 - 电源:5.5 V ~ 50 V 电压 - 负载:- 工作温度:-40°C ~ 105°C(TA) 安装类型:表面贴装 封装/外壳:20-WFQFN 裸露焊盘 供应商器件封装:20-QFN-EP(4x4) 标准包装:1
A4955GLPTR-T 功能描述:Motor Driver NMOS Parallel 20-TSSOP-EP 制造商:allegro microsystems, llc 系列:- 包装:剪切带(CT) 零件状态:有效 电机类型 - 步进:- 电机类型 - AC,DC:有刷直流 功能:控制器 - 换向,方向管理 输出配置:前置驱动器 - 半桥(2) 接口:并联 技术:NMOS 步进分辨率:- 应用:通用 电流 - 输出:- 电压 - 电源:5.5 V ~ 50 V 电压 - 负载:- 工作温度:-40°C ~ 105°C(TA) 安装类型:表面贴装 封装/外壳:20-TSSOP(0.173",4.40mm 宽)裸焊盘 供应商器件封装:20-TSSOP-EP 标准包装:1
A4955KLPTR-T 功能描述:Motor Driver NMOS Parallel 20-TSSOP-EP 制造商:allegro microsystems, llc 系列:汽车级,AEC-Q100 包装:剪切带(CT) 零件状态:有效 电机类型 - 步进:- 电机类型 - AC,DC:有刷直流 功能:控制器 - 换向,方向管理 输出配置:前置驱动器 - 半桥(2) 接口:并联 技术:NMOS 步进分辨率:- 应用:通用 电流 - 输出:- 电压 - 电源:5.5 V ~ 50 V 电压 - 负载:- 工作温度:-40°C ~ 125°C(TA) 安装类型:表面贴装 封装/外壳:20-TSSOP(0.173",4.40mm 宽)裸焊盘 供应商器件封装:20-TSSOP-EP 标准包装:1
A4956GESTR-T 功能描述:Motor Driver NMOS Parallel 20-QFN-EP (4x4) 制造商:allegro microsystems, llc 系列:- 包装:剪切带(CT) 零件状态:有效 电机类型 - 步进:- 电机类型 - AC,DC:有刷直流 功能:控制器 - 换向,方向管理 输出配置:前置驱动器 - 半桥(2) 接口:并联 技术:NMOS 步进分辨率:- 应用:通用 电流 - 输出:- 电压 - 电源:5.5 V ~ 50 V 电压 - 负载:- 工作温度:-40°C ~ 105°C(TA) 安装类型:表面贴装 封装/外壳:20-WFQFN 裸露焊盘 供应商器件封装:20-QFN-EP(4x4) 标准包装:1
A4956GLPTR-T 功能描述:Motor Driver NMOS Parallel 20-TSSOP-EP 制造商:allegro microsystems, llc 系列:- 包装:剪切带(CT) 零件状态:有效 电机类型 - 步进:- 电机类型 - AC,DC:有刷直流 功能:控制器 - 换向,方向管理 输出配置:前置驱动器 - 半桥(2) 接口:并联 技术:NMOS 步进分辨率:- 应用:通用 电流 - 输出:- 电压 - 电源:5.5 V ~ 50 V 电压 - 负载:- 工作温度:-40°C ~ 105°C(TA) 安装类型:表面贴装 封装/外壳:20-TSSOP(0.173",4.40mm 宽)裸焊盘 供应商器件封装:20-TSSOP-EP 标准包装:1