MAX17082GTL+ Maxim Integrated Products, MAX17082GTL+ Datasheet - Page 36

• Manufacturer Part Number: MAX17082GTL+
• Description: IC CTLR PWM DUAL IMVP-6.5 40TQFN
• Manufacturer: Maxim Integrated Products
• Series: Quick-PWM™r

Specifications of MAX17082GTL+

• Applications: Controller, Intel IMVP-6.5™
• Voltage - Input: 4.5 ~ 5.5 V
• Number Of Outputs: 1
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 40-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Lead Free Status / Rohs Status: Details

Dual-Phase, Quick-PWM Controllers for
IMVP-6+/IMVP-6.5 CPU Core Power Supplies
Figure 8. PSI Transition
When PSI is pulled low, the MAX17021/MAX17082/
MAX17482 immediately disable phase 2 (DH2 and DL2
forced low), blank PHASEGD high impedance, and
enter single-phase PWM operation (see Figure 8).
When PSI is pulled high, the MAX17021/MAX17082/
MAX17482 enable phase 2. PHASEGD is blanked high
impedance for 32 switching cycles on DH2, allowing
sufficient time/cycles for phases 1 and 2 to achieve cur-
rent balance. In a typical IMVP-6 application, the VID is
reduced by 1 LSB (12.5mV) when PSI is pulled low,
and increased by 1 LSB when PSI is pulled high.
During soft-shutdown, and normal operation—when the
CPU is actively running (DPRSLPVR = low)—the
MAX17021/MAX17082/MAX17482 operate with the low-
noise, forced-PWM control scheme. Forced-PWM oper-
ation disables the zero-crossing comparators of all
active phases, forcing the low-side gate-drive wave-
36
______________________________________________________________________________________
Forced-PWM Operation (Normal Mode)
PWM CONTROL
VID (D0–D6)
CPU LOAD
CPU CORE
CPU FREQ
INTERNAL
PHASEGD
VOLTAGE
PWRGD
CLKEN
PSI
2-PHASE PWM
BLANK HIGH IMPEDANCE
BLANK LOW
P P S S I I Transitions
20μs typ
t
BLANK
1-PHASE PWM
BLANK HIGH IMPEDANCE
forms to constantly be the complement of the high-side
gate-drive waveforms. This keeps the switching fre-
quency constant and allows the inductor current to
reverse under light loads, providing fast, accurate neg-
ative output-voltage transitions by quickly discharging
the output capacitors.
Forced-PWM operation comes at a cost: the no-load 5V
bias supply current remains between 10mA to 50mA
per phase, depending on the external MOSFETs and
switching frequency. To maintain high efficiency under
light-load conditions, the processor can switch the con-
troller to a low-power pulse-skipping control scheme
after entering suspend mode.
PSI determines how many phases are active when
operating in forced-PWM mode (DPRSLPVR = low).
When PSI is pulled low, the main phase remains active
but the secondary phase is disabled (DH2 and DL2
forced low).
32 SWITCHING CYCLES ON DH2
BLANK HIGH IMPEDANCE
BLANK LOW
2-PHASE PWM
20μs typ
t
BLANK