Motore di ricerca datesheet componenti elettronici |
|
LB11826 Scheda tecnica(PDF) 9 Page - ON Semiconductor |
|
LB11826 Scheda tecnica(HTML) 9 Page - ON Semiconductor |
9 / 11 page LB11826 No.7109-9/11 Continued from preceding page. Pin No. Pin name Pin function Equivalent circuit 22 21 24 23 26 25 IN1+ IN1- IN2+ IN2- IN3+ IN3- Hall amplifier input. IN+ > IN- is the input high state, and the reverse is the input low state. It is recommended that the Hall signal has an amplitude of 100mVp-p (differential) or more. Connect a capacitor between the IN+ and IN- inputs if there is noise in the Hall sensor signals. 300 Ω 300 Ω 22 24 26 21 23 25 VREG 27 F/R Forward/reverse control pin. Low : 0V to 1.5V High : 3.5V to VREG H level when open. Hysteresis width about 0.5V. 27 VREG 2k Ω 22k Ω LB11826 Description 1. Speed control circuit This IC performs speed control by using both the speed discriminator circuit and PLL circuit. The speed control circuit outputs the error signal once for every two cycles of FG (one FG cycle counted). The PLL circuit outputs the phase error signal once for each cycle of FG. As the FG servo frequency is calculated as follows, the motor speed is set with the number of FG pulses and clock frequency. fFG (servo) = fCLK/512 fCLK : Clock frequency This IC achieves variable speed control with ease when combined with LB11825M. 2. Output drive circuit This IC employs a direct PWM drive method to minimize the power loss at output. The output Tr is always saturated at ON, and the motor drive force is adjusted through change of the duty at which the output is turned ON. Since the output PWM switching is made with the lower-side output Tr, it is necessary to connect the schottky diode between OUT and VCC (because the through current flows at an instant when the lower-side Tr is turned ON if the diode with a short reverse recovery time is not used). The diode between OUT and GND is incorporated. When the large output current presents problem (waveform disturbance at kickback on the lower side), connect a commutating diode or schottky diode externally. 3. Current limiting circuit The current limiting circuit performs limiting with the current determined from I = VRF/Rf (VRF = 0.5Vtyp, Rf : current detector resistance) (that is, this circuit limits the peak current). Limiting operation includes decrease in the output on-duty to suppress the current. 4. Power save circuit This IC enters the power save condition to decrease the current dissipation in the stop mode. In this condition, the bias current of most of circuits is cut off. Even in the power save condition, the 5 V regulator output is given. 5. Reference clock This is entered from the external signal source (1MHz max) via a resistor (reference : about 5.1k Ω) in series with the XI pin. The XO pin is left open. Input signal source levels : Low-level voltage : 0 to 0.8V High-level voltage : 2.5 to 5.0V |
Codice articolo simile - LB11826 |
|
Descrizione simile - LB11826 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEETIT.COM |
Lei ha avuto il aiuto da alldatasheet? [ DONATE ] |
Di alldatasheet | Richest di pubblicita | contatti | Privacy Policy | scambio Link | Ricerca produttore All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |