Electronic Components Datasheet Search |
|
ISL9001IRMZ-T Datasheet(PDF) 9 Page - Intersil Corporation |
|
ISL9001IRMZ-T Datasheet(HTML) 9 Page - Intersil Corporation |
9 / 11 page 9 FN9231.2 March 28, 2008 Block Diagram Functional Description The ISL9001 contains all circuitry required to implement a high performance LDO. High performance is achieved through a circuit that delivers fast transient response to varying load conditions. In a quiescent condition, the ISL9001 adjusts its biasing to achieve the lowest standby current consumption. The device also integrates current limit protection, smart thermal shutdown protection, and soft-start. Smart Thermal shutdown protects the device against overheating. Power Control The ISL9001 has an enable pin (EN) to control power to the LDO output. When EN is low, the device is in shutdown mode. During this condition, all on-chip circuits are off, and the device draws minimum current, typically less than 0.1µA. When the enable pin is asserted, the device first polls the output of the UVLO detector to ensure that VIN voltage is at least about 2.1V. Once verified, the device initiates a start-up sequence. During the start-up sequence, trim settings are first read and latched. Then, sequentially, the bandgap, reference voltage and current generation circuitry power-up. Once the references are stable, a fast-start circuit quickly charges the external reference bypass capacitor (connected to the CBYP pin) to the proper operating voltage. Once the bypass capacitor has been charged, the LDO powers up. During operation, whenever the VIN voltage drops below about 1.84V, the ISL9001 immediately disables the LDO output. When VIN rises back above 2.1V, the device re-initiates its start-up sequence and LDO operation will resume automatically. Reference Generation The reference generation circuitry includes a trimmed bandgap, a trimmed voltage reference divider, a trimmed current reference generator, and an RC noise filter. The filter includes the external capacitor connected to the CBYP pin. A 0.01µF capacitor connected to CBYP implements a 100Hz lowpass filter, and is recommended for most high performance applications. For the lowest noise application, a 0.1µF CBYP capacitor should be used. This filters the reference noise to below the 10Hz to 1kHz frequency band, which is crucial in many noise-sensitive applications. The bandgap generates a zero temperature coefficient (TC) voltage for the reference divider. The reference divider provides the regulation reference, POR detection thresholds, and other voltage references required for current generation and over-temperature detection. The current generator outputs references required for adaptive biasing as well as references for LDO output current limit and thermal shutdown determination. VO GND BANDGAP AND TEMPERATURE SENSOR UVLO VIN SHORT CIRCUIT, THERMAL PROTECTION, SOFT-START EN CONTROL LOGIC CBYP 1.0V 0.94V 0.9V POR GND POR DELAY 1.0V VO CPOR VOLTAGE AND REFERENCE GENERATOR + - + - ISL9001 |
Similar Part No. - ISL9001IRMZ-T |
|
Similar Description - ISL9001IRMZ-T |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | 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 |