- 您现在的位置：买卖IC网 > PDF目录98171 > TC649VOART BRUSHLESS DC MOTOR CONTROLLER, PDSO8 PDF资料下载
参数资料
| 型号： | TC649VOART |
| 元件分类： | 运动控制电子 |
| 英文描述： | BRUSHLESS DC MOTOR CONTROLLER, PDSO8 |
| 封装： | SOIC-8 |
| 文件页数： | 13/17页 |
| 文件大小： | 119K |
| 代理商： | TC649VOART |
5
TC649-2 12/05/00
TC649
2001 Microchip Technology Inc.
DS21449A
PWM Fan Speed Controller with Auto-Shutdown
causes a corresponding dV/dt across the sense resistor,
RSENSE. The waveform on RSENSE is differentiated and
converted to a logic-level pulse-train by CSENSE and the
internal signal processing circuitry. The presence and fre-
quency of this pulse-train is a direct indication of fan opera-
tion. See the Applications section for more details.
FAULT Output
Pulses appearing at SENSE due to the PWM turning
on are blanked, and the remaining pulses are filtered by a
missing pulse detector. If consecutive pulses are not de-
tected for thirty-two PWM cycles (
≈1 Sec if CF = 1F), the
Diagnostic Timer is activated, and VOUT is driven continu-
ously for three PWM cycles (
≈100msec if CF = 1F). If a
pulse is not detected within this window, the Start-up Timer
is triggered (see Start-up Timer section). This should clear
a transient fault condition. If the Missing Pulse Detector
times out again, the PWM is stopped, and FAULT goes low.
When FAULT is activated due to this condition, the device is
latched in Shutdown Mode and will remain off indefinitely.
The TC649 is thus prevented from attempting to drive a fan
under catastrophic fault conditions.
One of two things will restore operation: Cycling power
off and then on again; or pulling VIN below VSHDN and
releasing it to a level above VREL. When one of these two
conditions is satisfied, the normal startup cycle is triggered,
and operation will resume if the fault has been cleared.
Auto-Shutdown Mode
If the voltage on VIN becomes less than the voltage on
VAS, the fan is automatically shut off (Auto-Shutdown Mode).
The TC649 exits Auto-Shutdown Mode when the voltage on
VIN becomes higher than the voltage on VAS by VHAS, the
Auto-Shutdown Hysteresis Voltage (see Figure 10). The
Start-up Timer is triggered, and normal operation is re-
sumed on exiting Auto-Shutdown Mode. The FAULT output
is unconditionally inactive in Auto-Shutdown Mode.
Shutdown Mode (Reset)
If an unconditional shutdown and/or device reset is
desired, the TC649 may be placed in Shutdown Mode by
forcing VIN to a logic low, i.e., VIN < VSHDN (see Figure 10).
In this mode, all functions cease, and the FAULT output is
unconditionally inactive. The fan will remain off regardless of
the voltage on VIN. The TC649 should not be shut down
unless all heat producing activity in the system is at a
negligible level. The TC649 exits Shutdown Mode when VIN
becomes greater than VREL, the Release Voltage. (Assum-
ing VIN > VAS + VHAS).
Entering Shutdown Mode also performs a complete
device reset. Shutdown Mode resets the TC649 into its
power-up state. The start-up and fault timers are cleared,
and any current faults are cleared. FAULT is unconditionally
inactive in Shutdown Mode. Upon exiting Shutdown Mode
(VIN > VREL), the Start-up Timer will be triggered, and normal
operation will resume, assuming no fault conditions exist.
Note: if VIN < VAS when the device exits Shutdown Mode,
the fan will not restart, but will be in Auto-Shutdown Mode.
If a Fan Fault has occurred and the device has latched
itself into Shutdown Mode, performing a reset will not clear
the fault unless VIN > (VAS + VHAS). If VIN is not greater than
(VAS + VHAS) upon exiting Shutdown Mode, the fan will not
be restarted, and, therefore, there is no way to establish that
the Fan Fault has been cleared. To ensure that a complete
Reset takes place, the user’s circuitry must ensure that
VIN > (VAS + VHAS) when the device is released from
Shutdown Mode. A recommended algorithm for manage-
ment of the TC649 by a host microcontroller or other external
circuitry is given in the applications section.
A small amount of hysteresis, typically one percent of
VDD, (50mV at VDD = 5.0V) is designed into the VSHDN/VREL
threshold. The levels specified for VSHDN and VREL in the
Electrical Characteristics section include this hysteresis
plus adequate margin to account for normal variations in the
absolute value of the threshold and hysteresis.
CAUTION: Shutdown Mode is unconditional. That is,
the fan will remain off regardless of system temperature, i.e.,
the voltage on VIN.
SYSTEM BEHAVIOR
The flowcharts describing the TC649’s behavioral algo-
rithm are shown in Figure 2. They can be summarized as
follows:
Power-Up
(1) Assuming the device is not being held in Shutdown
mode (VIN > VAS);
(2) Turn VOUT output on for 32 cycles of the PWM clock.
This ensures that the fan will start from a dead stop.
(3) During this Start-up Timer, if a fan pulse is detected,
branch to Normal Operation; if none are received...
(4) Activate the 32-cycle Start-up Timer one more time
and look for fan pulse. If a fan pulse is detected,
proceed to Normal Operation. If none are received...
(5) Proceed to Fan Fault.
(6) End.
相关PDF资料 |
PDF描述 |
|---|---|
| TC649VUATR | BRUSHLESS DC MOTOR CONTROLLER, PDSO8 |
| TC649VOATR | BRUSHLESS DC MOTOR CONTROLLER, PDSO8 |
| TC649EUATR | BRUSHLESS DC MOTOR CONTROLLER, PDSO8 |
| TC655EUNTR | BRUSHLESS DC MOTOR CONTROLLER, PDSO10 |
| TC655EUN | BRUSHLESS DC MOTOR CONTROLLER, PDSO10 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| TC649VOATR | 功能描述:马达/运动/点火控制器和驱动器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 产品:Stepper Motor Controllers / Drivers 类型:2 Phase Stepper Motor Driver 工作电源电压:8 V to 45 V 电源电流:0.5 mA 工作温度:- 25 C to + 125 C 安装风格:SMD/SMT 封装 / 箱体:HTSSOP-28 封装:Tube |
| TC649VPA | 功能描述:马达/运动/点火控制器和驱动器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 产品:Stepper Motor Controllers / Drivers 类型:2 Phase Stepper Motor Driver 工作电源电压:8 V to 45 V 电源电流:0.5 mA 工作温度:- 25 C to + 125 C 安装风格:SMD/SMT 封装 / 箱体:HTSSOP-28 封装:Tube |
| TC649VUA | 功能描述:马达/运动/点火控制器和驱动器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 产品:Stepper Motor Controllers / Drivers 类型:2 Phase Stepper Motor Driver 工作电源电压:8 V to 45 V 电源电流:0.5 mA 工作温度:- 25 C to + 125 C 安装风格:SMD/SMT 封装 / 箱体:HTSSOP-28 封装:Tube |
| TC649VUATR | 功能描述:马达/运动/点火控制器和驱动器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 产品:Stepper Motor Controllers / Drivers 类型:2 Phase Stepper Motor Driver 工作电源电压:8 V to 45 V 电源电流:0.5 mA 工作温度:- 25 C to + 125 C 安装风格:SMD/SMT 封装 / 箱体:HTSSOP-28 封装:Tube |
| TC6-4A11 | 制造商:FERROXCUBE 制造商全称:Ferroxcube International Holding B.V. 功能描述:Ferrite toroids |
发布紧急采购，3分钟左右您将得到回复。