Electronic Components Datasheet Search |
|
LT3599 Datasheet(PDF) 7 Page - Linear Technology |
|
LT3599 Datasheet(HTML) 7 Page - Linear Technology |
7 / 26 page LT3599 3599fd pin FuncTions CTRL: LED Current Control. If the CTRL pin is not used, tie this pin to VREF. DISABLE4: Allows Disabling Channel 4. Connect to VREF to disable channel 4. If channel 4 is disabled, the LED4 pin should be connected to the LED3 pin. Connect DISABLE4 to ground to allow operation of channel 4. Exposed Pad: Ground. The ground for the IC should be soldered to a continuous copper ground plane under the LT3599 die. FB: Feedback Pin for Overvoltage Protection. Reference voltage is 1.223V. Connect the resistive divider tap here. Minimize trace area at FB. Set VOUT according to VOUT = 1.223(1 + R2/R1) when overvoltage protection occurs. GND: Analog Ground. Tie directly to local ground plane. Connect RT, ISET and TSET resistors between this local ground plane and their respective pins. ISET: Programs Led Current for Each String. A resistor to ground programs LED currents between 30mA and 120mA. LED1-4: LED String Output. Connect the bottom cathode of each LED string to these pins. OPENLED: Open LED Flag. An open-collector output when any LED string opens. NC: No Connect Pins. Can be left open or connected to any ground plane. PWM: Input Pin for PWM Dimming Control. Above 1V allows converter switching, and below 0.4V disables switching with VC pin level maintained. A PWM signal driving the PWM pin provides accurate dimming control. The PWM signal can be driven from 0V to 5V. If unused, the pin should be connected to VREF. RT: A Resistor to Ground Which Programs Switching Frequency Between 200kHz and 2.1MHz. For SYNC func- tion, choose the resistor to program a frequency 20% slower than the SYNC pulse frequency. Do not leave this pin open. SHDN/UVLO: The SHDN/UVLO pin has an accurate 1.36V threshold and can be used to program an undervoltage lockout (UVLO) threshold for system input supply using a resistor divider from supply to ground. A 4µA pin current hysteresis allows programming of undervoltage lockout (UVLO) hysteresis. 1.36V turns the part on and removes a 4µA sink current from the pin. SHDN/UVLO = 0V reduces VINcurrent<0.1µA.SHDN/UVLOcanbedirectlyconnected to VIN. Do not leave this pin open. SHORTLED: Indicates a high side short (LED pin shorted to VOUT). This is an open-collector output. SS: Soft-Start Pin. Place a soft-start capacitor here. Upon start-up, a 11µA current charges the capacitor. Use a larger capacitor for a slower start-up. SW: Switch Pin. This is the collector of the internal NPN power switch. Minimize the metal trace area connected to this pin to minimize EMI. SYNC:FrequencySynchronizationPin.Thisinputallowsfor synchronizingtheoperatingfrequencytoanexternalclock. The RT resistor should be chosen to program a switching frequency 20% slower than SYNC pulse frequency. This pin should be grounded if this feature is not used. TSET: Programs LT3599 junction temperature breakpoint, beyond which LED currents will begin to decrease. An internal VPTAT threshold (see Block Diagram) increases with junction temperature. When VPTAT exceeds TSET pin voltage, LED currents are decreased. If the function is not required, connect TSET pin to VREF pin. If the TSET pin is not used, tie this pin to VREF. VC: Error Amplifier Output Pin. Tie the external compensa- tion network to this pin. VIN: Input Supply Pin. Must be locally bypassed with a capacitor to ground. VO_SW: Drain of an Internal PMOS. The internal PMOS disconnects the feedback resistors from the VOUT pin during shutdown and when the PWM pin is low. VOUT: Output Pin. This pin provides power to all LEDs. VREF:BandgapVoltageReference.Internallysetto1.227V. This pin can supply up to 100µA. Can be used to program the CTRL pin voltage using resistor dividers to ground. |
Similar Part No. - LT3599 |
|
Similar Description - LT3599 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List 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 |