データシートサーチシステム |
|
L6258 データシート(PDF) 8 Page - STMicroelectronics |
|
L6258 データシート(HTML) 8 Page - STMicroelectronics |
8 / 18 page Charge Pump Circuit To ensure the correct driving of the high side driv- ers a voltage higher than Vs is supplied on the Vboot pin. This boostrap voltage is not needed for the low side power DMOS transistors because their sources terminals are grounded. To produce this voltage a charge pump method is used. It is made by using two external capacitors; one con- nected to the internal oscillator (CP) and the other (Cboot) to storage the overvoltage needed for the driving the gates of the high side DMOS. The value suggested for the capacitors are: Cboot Storage Capacitor 100 nF CP Pump Capacitor 10 nF Current Control LOOP The current control loop is a transconductance amplifier working in PWM mode. The motor current is a function of the pro- grammed DAC voltage. To keep under control the output current, the cur- rent control modulates the duty cycle of the two outputs OUT_A and OUT_B, and a sensing resis- tor Rs is connected in series with the motor wind- ing in order to produce a voltage feedback com- pared with the programmed voltage of the DAC . The duty cycle modulation of the two outputs is generated comparing the voltage at the outputs of the error amplifier, with the two triangular wave references . In order to drive the output bridge with the duty cycle modulation explained before, the signals driving each output ( OUTA & OUTB ) are gener- ated by the use of the two comparators having as reference two triangular wave signals Tri_0 and Tri_180 of the same amplitude, the same average value (in our case Vr), but with a 180° of phase shift each other. The two triangular wave references are respec- tively applied to the inverting input of the first comparator and to the non inverting input of the second comparator . The other two inputs of the comparators are con- nected together to the error amplifier output volt- age resulting by the difference between the pro- grammed DAC. The reset of the comparison between the mentioned signals is shown in fig. 3. Tri_0 Tri_180 Error Ampl. Output First Comp. Output Second Comp. Output Figure 3. Output comparator waveforms L6258 8/18 |
同様の部品番号 - L6258 |
|
同様の説明 - L6258 |
|
|
リンク URL |
プライバシーポリシー |
ALLDATASHEET.JP |
ALLDATASHEETはお客様のビジネスに役立ちますか? [ DONATE ] |
Alldatasheetは | 広告 | お問い合わせ | プライバシーポリシー | リンク交換 | メーカーリスト 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 |