전자부품 데이터시트 검색엔진 |
|
STP4CMPQTR 데이터시트(PDF) 10 Page - STMicroelectronics |
|
STP4CMPQTR 데이터시트(HTML) 10 Page - STMicroelectronics |
10 / 22 page Detailed description STP4CMP 10/22 Doc ID 15770 Rev 2 5 Detailed description The STP4CMP is a charge-pump-based 4-channel LED driver designed for RGB illumination or LCD display backlighting, using constant current topology. Each of the 4 channels can be controlled independently. When ONx is pulled high, a constant current is sunk into the LEDx pin when a LED is connected. This constant current is defined or programmed by the value of the resistor at ISETX pin. 5.1 Enable pin (EN) The active high enable input pin is used to shut down the whole device. When this pin is pulled low, the device enters into shutdown mode with only 5 µA max. current consumption. An internal pulled down of 300 k Ω is present at this pin. 5.2 LED turn-on pin (ONx) When the EN pin is pulled high, the STP4CMP provides the flexibility to control the turning- ON/OFF on the 4 channels independently through the 4 active high ON pins. To control the brightness of each LED channel, it is possible to drive the selected ON pin with a PWM signal with a frequency up to a minimum TON/TOFF of 33 µs. An internal pull-down of 300 kΩ is present at these pins. 5.3 Programmable output current The LED currents at the 4 channels are programmed individually through a resistor connected from Iset1, Iset2, Iset3, Iset4 to ground. The relationship between the resistor (RSET) and the LED current (ILED) is governed by this equation: Equation 1 RSET = 16 * (1.22 / ILED) 5.4 Charge pump The STP4CMP charge pump can be disabled or enabled according to the CP_sel pin. When enabled (CP_sel is high), the charge pump provides a clamping voltage of typ 5.0 V to ensure enough headroom to drive the LEDs. An internal pull-down of 300 k Ω is present at this pin. The charge pump can be disabled by pulling low the CP_sel pin, based on the VCC and forward voltage of the LEDs used. This allows the connection of VCC directly to VOUT to drive the external LEDs. At VCC 3.1 V, the charge pump is able to maintain regulation at 5 V when the total current drawn from it (at VOUT pin) is ≤ 120 mA. At 2.7 ≤ VCC < 3.1 V, in order for the charge pump to maintain regulation at 5 V, the total current drawn from it (at VOUT pin) must be lowered to ≤ 40 mA. |
유사한 부품 번호 - STP4CMPQTR |
|
유사한 설명 - STP4CMPQTR |
|
|
링크 URL |
개인정보취급방침 |
ALLDATASHEET.CO.KR |
ALLDATASHEET 가 귀하에 도움이 되셨나요? [ DONATE ] |
Alldatasheet는? | 광고문의 | 운영자에게 연락하기 | 개인정보취급방침 | 링크교환 | 제조사별 검색 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 |