MIC2182-3.3YM Microchip

MIC2182 Micrel MIC2182 High-Efficiency Synchronous Buck Controller General Description Features Micrels MIC2182 is a synchronous buck (step-down) switch- 4.5V to 32V Input voltage range ing regulator controller. An all N-channel synchronous archi- 1.25V to 6V Output voltage range tecture and powerful output drivers allow up to a 20A output 95% efficiency current capabilty. The PWM and skip-mode control scheme 300kHz oscillator frequency allows efficiency to exceed 95% over a wide range of load Current sense blanking current, making it ideal for battery powered applications, as 5 impedance MOSFET Drivers well as high current distributed power supplies. Drives N-channel MOSFETs 600 A typical quiescent current (skip-mode) The MIC2182 operates from a 4.5V to 32V input and can Logic controlled micropower shutdown (I < 0.1 A) operate with a maximum duty cycle of 86% for use in low- Q Current-mode control dropout conditions. It also features a shutdown mode that Cycle-by-cycle current limiting reduces quiescent current to 0.1 A. Built-in undervoltage protection The MIC2182 achieves high efficiency over a wide output Adjustable undervoltage lockout current range by automatically switching between PWM and Easily synchronizable skip mode. Skip-mode operation enables the converter to Precision 1.245V reference output maintain high efficiency at light loads by turning off circuitry 0.6% total regulation pertaining to PWM operation, reducing the no-load supply 16-pin SOP and SSOP packages current from 1.6mA to 600 A. The operating mode is inter- Frequency foldback overcurrent protection nally selected according to the output load conditions. Skip Sustained short-circuit protection at any input voltage mode can be defeated by pulling the PWM pin low which 20A output current capability reduces noise and RF interference. Applications The MIC2182 is available in a 16-pin SOP (small-outline package) and SSOP (shrink small-outline package) with an DC power distribution systems operating range from 40C to +85C. Notebook and subnotebook computers PDAs and mobile communicators Wireless modems Battery-operated equipment Typical Application C11 V IN D2 MIC2182-3.3BSM 22uf 4.5V to 30V* SD103BWS 10 11 35V VIN VDD C9 x2 C5 R7 14 4.7 F 0.1 F BST C6 100k 16V 0.1 F 6 16 L1 EN/UVLO HSD Q2* V R2 OUT 10 H Si4884 3.3V/4A 0.02 2 15 PWM VSW C4 C7 13 D1 1nF LSD Q1* 220uf B140 Si4884 10V 2 1 12 SS PGND GND 3 8 COMP CSH C13, 1nF R1 5 9 C3 SYNC VOUT 2k 0.1 F 7 * 30V maximum input voltage limit is due VREF C2 to standard 30V MOSFET selection. 2.2nF SGND C1 See Application Information section for 4 0.1 F GND 5V to 3.3V/10A and other circuits. 4.5V30V* to 3.3V/4A Converter Micrel, Inc. 1849 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 474-1000 MIC2182 Micrel Ordering Information Part Number Voltage Temperature Range Package Lead Finish MIC2182BM Adjustable 40C to +85C 16-pin narrow SOP Standard MIC2182-3.3BM 3.3V 40C to +85C 16-pin narrow SOP Standard MIC2182-5.0BM 5.0V 40C to +85C 16-pin narrow SOP Standard MIC2182BSM Adjustable 40C to +85C 16-pin narrow SSOP Standard MIC2182-3.3BSM 3.3V 40C to +85C 16-pin narrow SSOP Standard MIC2182-5.0BSM 5.0V 40C to +85C 16-pin narrow SSOP Standard MIC2182YM Adjustable 40C to +85C 16-pin narrow SOP Pb-Free MIC2182-3.3YM 3.3V 40C to +85C 16-pin narrow SOP Pb-Free MIC2182-5.0YM 5.0V 40C to +85C 16-pin narrow SOP Pb-Free MIC2182YSM Adjustable 40C to +85C 16-pin narrow SSOP Pb-Free MIC2182-3.3YSM 3.3V 40C to +85C 16-pin narrow SSOP Pb-Free MIC2182-5.0YSM 5.0V 40C to +85C 16-pin narrow SSOP Pb-Free Pin Configuration MIC2182 MIC2182-x.x SS 1 16 HSD SS 1 16 HSD PWM 2 15 VSW PWM 2 15 VSW COMP 3 14 BST COMP 3 14 BST SGND 4 13 LSD SGND 4 13 LSD SYNC 5 12 PGND SYNC 5 12 PGND EN/UVLO 6 11 VDD EN/UVLO 6 11 VDD FB 7 10 VIN VREF 7 10 VIN CSH 8 9 VOUT CSH 8 9 VOUT Adjustable Fixed 16-pin SOP (M) 16-pin SOP (M) 16-Pin SSOP (SM) 16-Pin SSOP (SM) M9999-042204 2 April 22, 2004