IR3502MPBF International Rectifier, IR3502MPBF Datasheet - Page 18

• Manufacturer Part Number: IR3502MPBF
• Description: Complete VR11.0 or VR11.1 power solution.
• Manufacturer: International Rectifier

Specifications of IR3502MPBF

• Package: 32-Lead MLPQ
• Circuit: X-Phase Control IC
• Switch Freq (khz): 250kHz to 1.5MHz
• Pbf: PbF Option Available

Current Monitor (IMON)
The control IC generates a current monitor signal IMON using the VDRP voltage and the VDAC reference, as
shown in Figure 10. This voltage is thermally compensated for the inductor DCR variation. The voltage at this pin
reports the average load current information without being referenced to VDAC. The slope of the IMON signal with
respect to the load current can be adjusted with the resistors RTCMP2 and RTCMP3. The IMON signal is clamped
at 1.03V in order to facilitate direct interfacing with the CPU.
ENABLE
VDAC
VRRDY
(12V)
VCC
SS/DEL
EAOUT
VOUT
1.1V
Page 18 of 39
3.92V
4.0V
1.4V
3V
START DELAY (TD1)
Figure 9 Start-up sequence of converter with boot voltage
Figure 10 Current report signal (IMON) implementation
VDAC
+
-
VDAC
Buffer
50mV
VDRP
Control IC
200k
100k
SOFT START
TIME (TD2)
200k
200k
200k
-
+
200k
+
-
Thermal
Comp
Amplifier
VDRP
Buffer
VID SAMPLE
TIME (TD3)
1.03
0
+
-
VID
VDRP
VN
DAC_BUFF
IMON
IIN
TD4
From Phase ICs
VRRDY DELAY
TIME (TD4+TD5)
RTCMP1
RTCMP2
RTCMP3
TD5
RTHERM
July 28, 2009
NORMAL OPERATION
IR3502