- 您现在的位置：买卖IC网 > PDF目录67755 > LB1923M BRUSHLESS DC MOTOR CONTROLLER, 0.03 A, PQFP44 PDF资料下载
参数资料
| 型号： | LB1923M |
| 元件分类： | 运动控制电子 |
| 英文描述： | BRUSHLESS DC MOTOR CONTROLLER, 0.03 A, PQFP44 |
| 封装： | QFP-44 |
| 文件页数： | 2/19页 |
| 文件大小： | 152K |
| 代理商： | LB1923M |
LB1923M
No.6067-10/19
IC Operation Description
1. Speed Control Circuit
This IC implements speed control using the combination of a speed discriminator circuit and a PLL circuit. The
speed discriminator and the PLL circuit output (using a charge pump technique) an error signal once every two FG
periods.
As compared to the earlier technique in which only a speed discriminator circuit was used, the combination of a
speed discriminator and a PLL circuit allows variations in motor speed to be better suppressed when a motor that
has large load variations is used. The FG servo frequency is controlled to be the same frequency as the clock signal
input to the CLK pin. This means that the motor speed can be changed by changing the clock frequency.
2. VCO Circuit
The LB1821M includes an on-chip VCO circuit to generate the reference signal for the speed discriminator circuit.
The reference signal frequency is determined by the following formula.
fVCO = fCLK × number of counts
fVCO: Reference signal frequency
fCLK: Frequency of the externally input clock signal
The range over which the reference signal can be varied is determined by the resistor and capacitor connected to the
R pin (pin 36) and the C pin (pin 37) and by the VCO loop filter constants (the external constants connected to pins
41 and 42).
(Reference Values)
Supply voltage
R (k
)
C (pF)
VCC = 5V
4.7
390
VCC = 6.3V
4.7
820
The value of R must not be less than 2.7k
.
Applications can handle a wider range of speed variations than would be possible if a fixed number of counts was
used by changing the number of discriminator counts (which is related to the divisor in the VCO circuit). The
number of counts can be switched between 64, 128, 256, and 512 by setting the N1 (pin 10) and N2 (pin 11) pins.
3. Output Drive Circuit
To reduce power loss in the output, this IC adopts the direct PWM drive technique. The output transistors (which are
external to the IC) are always saturated when on, and the motor drive output is adjusted by changing the duty with
which the output is on. Since the (external) output switching is handled by the upper side output transistors, a
Schottky diode or similar device must be connected between the output (OUT) and ground. This is because a
through current will flows at the instant the upper side output transistors turn on if a diode with a short reverse
recovery time is not used. A rectifying diode can be used between OUT and VCC. Transistors that have no parasitic
diodes must be used for the lower side output transistors. If these transistors have parasitic diode components, then
through currents will occur due to the reverse recovery time of the parasitic diodes despite the inclusion of the
external Schottky diodes.
4. Current Limiter Circuit
The current limiter circuit limits the (peak) current at the value I = VRF/Rf (VRF = 0.52V (typical), Rf: current
detection resistor). The current limitation operation consists of reducing the output duty to suppress the current.
5. Speed Lock Range
The speed lock range is ±6.25% of the fixed speed. When the motor speed is in the lock range, the LD pin (an open
collector output) goes low. If the motor speed goes out of the lock range, the motor on duty is adjusted according to
the speed error to control the motor speed to be within the lock range.
6. Notes on the PWM Frequency
The PWM frequency is determined by the resistor and capacitor connected to the CR pin.
fPWM ≈ 1/(0.48 × C × R)
A PWM frequency of between 15 and 25kHz is desirable. If the PWM frequency is too low, the motor may resonate
at the PWM frequency during motor control, and if that frequency is in the audible range, that resonation may result
in audible noise. If the PWM frequency is too high, the output transistor switching loss will increase. The external
resistor must not have a value under 30k
.
7. Hall Input Signals
Input signals with an amplitude greater than the hysteresis (60mV, maximum) are required for the Hall inputs. An
input amplitude of 100mV or greater is desirable, taking noise and other considerations into account. The Hall input
DC voltage must be set to fall within the common-mode input voltage range specifications.
相关PDF资料 |
PDF描述 |
|---|---|
| LB1946 | STEPPER MOTOR CONTROLLER, 1.75 A, PDFM28 |
| LC5511D | POWER FACTOR CONTROLLER, 18 kHz SWITCHING FREQ-MAX, DIP7 |
| LC5521D | 2.5 A POWER FACTOR CONTROLLER, 18 kHz SWITCHING FREQ-MAX, DIP7 |
| LC72137 | PLL FREQUENCY SYNTHESIZER, 40 MHz, PDIP22 |
| LC72137M | PLL FREQUENCY SYNTHESIZER, 40 MHz, PDSO20 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LB1923M-MPB-E | 制造商:ON Semiconductor 功能描述:3PHASE MOTOR PRE-DRIVER - Trays |
| LB1923M-TLM-E | 功能描述:马达/运动/点火控制器和驱动器 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 |
| LB1924 | 制造商:SANYO 制造商全称:Sanyo Semicon Device 功能描述:Power Brushless Motor Driver IC for Office Automation Equipment |
| LB1927 | 制造商:SANYO 制造商全称:Sanyo Semicon Device 功能描述:For Office Automation Equipment 3-phase Brushless Motor Driver |
| LB1927-E | 功能描述:马达/运动/点火控制器和驱动器 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 |
发布紧急采购，3分钟左右您将得到回复。