IR3510 DATA SHEET HOT-SWAP N+1 REDUNDANT XPHASE CONTROL IC DESCRIPTION The IR3510 Hot-Swap N+1 Redundant X-Phase Controller combines input isolation control for hot- swappable application, X-Phase VRM/VRD control and output OR-ing control for N+1 redundant application. It interfaces with microcontroller and X-Phase phase ICs to provide a full featured and flexible solution for powering high-end CPUs and servers. The IR3510 interfaces with system logic to receive ENABLE, VSET which is the analog reference voltage for controlling VRM output voltage, constant current limit OCPSET and OVP limit OVPSET. It feeds back to the system load current IO, VRM status VRRDY, OR-ing FETs status ORING and input fault IOCD. The IR3510 works with existing X-Phase phase ICs to provide a full featured multiphase VRM control, including soft-start, voltage regulation, constant current limit, remote sense and open sense leads protection. The IR3510 continuously monitors the 12V input current and VRM output voltage. Once the input current exceeds the programmable threshold, it goes to current limit mode and turn off the input FETs when the OC delay times out. It immediately turns off the input FETs when an OV condition is detected on the VRM output. It also has UVLO for both the 12V input and the supply voltage to the VRM. The IR3510 has built-in OR-ing control function for N+1 redundant application. When the VRM output voltage is higher than the output voltage bus, it turns on the OR-ing FETs When the VRM output is sinking current from the output voltage bus, it turns off the OR-ing FETs. FEATURES Two ENABLE thresholds for turning on input FET and VRM output Input isolation FET control for hot-swap, input OCP and output OVP Programmable input OCP limit and delay Input isolation FET short detection Integrated Charge Pump drives input isolation FETs and output OR-ing FETs Programmable 150KHz to 1MHz oscillator Programmable two-stage soft-start Analog voltage setting for output voltage control, OVP limit and OCP limit True remote voltage sense with open-sense-lead protection Programmable output impedance Gain adjustable analog load current report with thermal compensation capability Average Current Mode control improving current sharing between paralleled modules Constant output current limit Compatible with existing IR3086A and IR3088A Phase ICs OR-ing control with adjustable reverse current cut-off threshold Input Fault, VRRDY and OR-ing status indications Operation from 12V input with 9V Under-Voltage Lockout 6.8V Bias Voltage provides system reference 32-lead MLPQ 5x5mm package Page 1 of 36 IR Confidential May 18, 2009 IR3510 APPLICATION CIRCUIT IRF6635 1m/1W Rs +12V IN IRF6631 IRF6635 L VO+ C11 C12 C13 C14 IRF6635 GND GND C3 Rocset 1n 2k C4 10n Radj 1k C2 1u VBIAS R1 10 C1 Rosc 41.2k 0.1u 24 C19 ROSC 10n 1 23 VDAC VREF VCC Cx 0.1u 22 RMPOUT RMPOUT 2 21 ISHARE CX IIN 3 20 ENABLE EAOUT ENABLE EAOUT 4 U1 C8 100p VRRDY VRRDY IR3510 5 19 ORING ORING IFB R11 1K C7 10n 6 18 VSET VSET IO 7 R10 2k Rt OVP LIMIT OVPSET 8 17 R12 10K OCP LIMIT CURRENT OCPSET IGAIN R8 R9 2k NTC 1k IOCD Css Cd C6 100p 0.1u 10n R4 1k R7 C5 10k 10n R6 100k PACKAGE 24 ROSC 1 23 VREF VCC 22 RMPOUT 2 21 CX IIN 3 20 ENABLE EAOUT 4 U1 VRRDY IR3510 5 19 ORING IFB 6 18 VSET IO 7 OVPSET 8 17 OCPSET IGAIN ( MLPQ-32, 5x5 mm, 34C/W ) Page 2 of 36 IR Confidential May 18, 2009 32 9 VBIAS SS 31 ICS+ 10 30 IOCD ICS- 29 GATE I 11 VOSNS- 12 28 VOSNS+ LGND 13 OVPSNS 27 GATE O 14 26 VO OR+ 15 25 32 VFB OR- 9 VBIAS 16 IREF SS 31 ICS+ 10 30 IOCD ICS- 29 GATE I 11 VOSNS- 12 28 VOSNS+ LGND 13 OVPSNS 27 GATE O 14 26 VO OR+ 15 25 VFB OR- 16 IREF