HIP6302VCB Intersil, HIP6302VCB Datasheet - Page 13

• Manufacturer Part Number: HIP6302VCB
• Description: IC CTRLR PWM MULTIPHASE 16-SOIC
• Manufacturer: Intersil

Specifications of HIP6302VCB

• Pwm Type: Controller
• Number Of Outputs: 4
• Frequency - Max: 336kHz
• Voltage - Supply: 4.75 V ~ 5.25 V
• Buck: Yes
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 16-SOIC (3.9mm Width)
• Frequency-max: 336kHz
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Duty Cycle: -

Current Sensing and Balancing
Overview
The HIP6301V and HIP6302V sample the on-state voltage
drop across each synchronous MOSFET, Q
indication of the inductor current in that phase, see Figure 9.
Neglecting AC effects (to be discussed later), the voltage
drop across Q
Note that I
the total current (I
in use.
The voltage at Q
R
pin. This pin is held at virtual ground, so the current through
R
The I
following functions:
I
L
1. Detection of an overcurrent condition
ISEN
ISEN
=
r
----------------------
ISEN
R
DS ON
FB
resistor to develop the I
is shown in Equation 1:
ISEN
OVERCURRENT
(
L
current provides information to perform the
, the inductor current, is either 1/2, 1/3, or 1/4 of
TRIP
)
TO
(
Q2
REFERENCE
2
AMPLIFIER
FIGURE 9. SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM SHOWING CURRENT AND VOLTAGE SAMPLING
RFB
is simply r
ERROR
)
+
2
-
DAC
LT
’s drain, the PHASE node, is applied to the
RIN
), depending on how many phases are
Cc
COMPARATOR
CHANNELS
TO OTHER
DS(ON)
COMP
13
ISEN
GENERATOR
SAWTOOTH
CORRECTION
+
+
-
(Q
current through the ISEN
2
) x inductor current (I
DIFFERENCE
-
REFERENCE
-
2
+
, as an
AVERAGING
HIP6301V, HIP6302V
HIP6301V, HIP6302V
COMPARATOR
+
-
(EQ. 1)
HIP6301V
L
).
CURRENT
SENSING
CURRENT
SENSING
FROM
OTHER
CHANNELS
CIRCUIT
PWM
Overcurrent, Selecting R
The current detected through the R
with the current(s) detected in the other 1, 2, or 3 channels.
The averaged current is compared with a trimmed, internally
generated current, and used to detect an overcurrent
condition.
The nominal current through the R
50µA at full output load current, and the nominal trip point for
overcurrent detection is 165% of that value, or 82.5µA
(typical current levels) as shown in Equation 2. Therefore:
For a full load of 25A per phase, and an r
4mΩ, R
The overcurrent trip point would be 165% of 25A, or ~ 41A
per phase. The R
overcurrent trip point, but it is suggested to stay within ±25%
of nominal.
IR
2. Reduce the regulator output voltage with increasing load
3. Balance the I
ISEN
current (droop)
PWM
ISEN
=
ISEN
( )r
--------------------------------------------- -
I
L
= 2kΩ.
DS ON
50μA
(
ONLY ONE OUTPUT
L
HIP6601
ISEN
currents in multiple channels
)
STAGE SHOWN
RISEN
(
Q2
value can be adjusted to change the
CURRENT(S)
)
CHANNELS
INDUCTOR
Q2
VIN
ISEN
OTHER
FROM
Q1
ISEN
PHASE
ISEN
L01
IL
resistor should be
resistor is averaged
DS(ON)
VCORE
(Q
2
May 5, 2008
) of
FN9034.3
(EQ. 2)