ISL6267HRZ-T Intersil, ISL6267HRZ-T Datasheet - Page 30

• Manufacturer Part Number: ISL6267HRZ-T
• Description: IC PWM CTRLR MULTIPHASE 48TQFN
• Manufacturer: Intersil

Specifications of ISL6267HRZ-T

• Applications: Converter, AMD Fusion™ CPU GPU
• Voltage - Input: 4.75 V ~ 5.25 V
• Number Of Outputs: 2
• Voltage - Output: 0.0125 V ~ 1.55 V
• Operating Temperature: -10°C ~ 100°C
• Mounting Type: *
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ISL6267
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
PHASE1_NB
UGATE1_NB
LGATE1_NB
PWM2_NB
BOOT1_NB
ISUMN_NB
ISUMP_NB
SYMBOL
PHASE1
PHASE2
NTC_NB
UGATE1
LGATE1
LGATE2
UGATE2
PROG1
PROG2
ISUMN
BOOT1
PWM3
BOOT2
ISUMP
VCCP
VDD
VIN
30
TABLE 9. LAYOUT CONSIDERATIONS FOR THE ISL6267 CONTROLLER
Place the current sensing circuit in general proximity of the controller.
Place capacitor Cn very close to the controller.
Place the NTC thermistor next to VR1 phase-1 inductor (L1) so it senses the inductor temperature correctly.
Each phase of the power stage sends a pair of VSUMP and VSUMN signals to the controller. Run these two
signals traces in parallel fashion with decent width (>20mil).
IMPORTANT: Sense the inductor current by routing the sensing circuit to the inductor pads. Route R63 and R71
to Core VR phase-1 side pad of inductor L1. Route R88 to the output side pad of inductor L1. Route R65 and
R72 to Core VR phase-2 side pad of inductor L2. Route R90 to the output side pad of inductor L2. If possible,
route the traces on a different layer from the inductor pad layer and use vias to connect the traces to the center
of the pads. If no via is allowed on the pad, consider routing the traces into the pads from the inside of the
inductor. The following drawings show the two preferred ways of routing current sensing traces.
A capacitor (C17) decouples it to GND. Place it in close proximity to the controller.
No special consideration.
Use decent wide trace (>30mil). Avoid any sensitive analog signal trace from crossing over or getting close.
Run these two traces in parallel fashion with decent width (>30mil). Avoid any sensitive analog signal trace from
crossing over or getting close. Recommend routing PHASE1 trace to VR1 phase-1 high-side MOSFET (Q2 and
Q8) source pins instead of general copper.
Use decent width (>30mil). Avoid any sensitive analog signal trace from crossing over or getting close.
No special consideration.
A capacitor (C22) decouples it to GND. Place it in close proximity to the controller.
Use decent width (>30mil). Avoid any sensitive analog signal trace from crossing over or getting close.
Run these two traces in parallel fashion with decent width (>30mil). Avoid any sensitive analog signal trace from
crossing over or getting close. Recommend routing PHASE2 trace to VR1 phase-2 high-side MOSFET (Q4 and
Q10) source pins instead of general copper.
Use decent wide trace (>30mil). Avoid any sensitive analog signal trace from crossing over or getting close.
No special consideration.
Use decent width (>30mil). Avoid any sensitive analog signal trace from crossing over or getting close.
Run these two traces in parallel fashion with decent width (>30mil). Avoid any sensitive analog signal trace from
crossing over or getting close. Recommend routing PHASE1G trace to VR2 phase-1 high-side MOSFET source
pins instead of general copper.
Use decent wide trace (>30mil). Avoid any sensitive analog signal trace from crossing over or getting close.
No special consideration.
Place the NTC thermistor close to the thermal source that is monitored to determine GT V
throttling. Usually it is placed close to Northbridge VR phase-1 high-side MOSFET.
Place the current sensing circuit in general proximity to the controller.
Place capacitor Cn very close to the controller.
Place the NTC thermistor next to Northbridge VR phase-1 inductor (L1) so it senses the inductor temperature
correctly.
See ISUMN and ISUMP pins for layout guidelines of current-sensing trace routing.
A capacitor (C16) decouples it to GND. Place it in close proximity to the controller.
CURRENT-SENSING TRACES
ISL6267
VIAS
INDUCTOR
LAYOUT GUIDELINES
CURRENT-SENSING TRACES
(Continued)
INDUCTOR
CORE
thermal
January 31, 2011
FN7801.0