LTC3733_15 Datasheet, PDF (4/32 Pages) Linear Technology – 3-Phase, Buck Controllers for AMD CPUs

LTC3733/LTC3733-1
ELECTRICAL CHARACTERISTICS The q denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_CC = V_RUN = V_SS = 5V unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Oscillator and Phase-Locked Loop
f_NOM
f_LOW
f_HIGH
R_PLLTH
R_{PLL IN}
I_{PLL LPF}
R_RELPHS
Nominal Frequency
Lowest Frequency
Highest Frequency
PLLIN Input Threshold
PLLIN Input Resistance
Phase Detector Output Current
Sinking Capability
Sourcing Capability
Controller 2-Controller 1 Phase
Controller 3-Controller 1 Phase
V_PLLFLTR = 1.2V
V_PLLFLTR = 0V
V_PLLFLTR = 2.4V
LTC3733-1 Only
LTC3733-1 Only
LTC3733-1 Only
f_PLLIN < f_OSC
f_PLLIN > f_OSC
310
350
400
kHz
190
210
250
kHz
470
530
620
kHz
1
V
50
kΩ
20
µA
20
µA
120
Deg
240
Deg
No_CPU Detection
t_NOCPU
No-CPU Shutdown Latency
Differential Amplifier
After All VID Bits = “1”
0.5
1
µs
A_V
Differential Gain
V_OS
Input Offset Voltage
IN⁺ = IN^– = 1.2V, I_OUT = 1mA,
Input Referred; Gain = 1
0.995 1.000 1.005 V/V
0.5
5
mV
CM
Common Mode Input Voltage Range
0
5
V
CMRR
Common Mode Rejection Ratio
0V < IN⁺ = IN^– < 5V, I_OUT = 1mA, Input Referred
50
70
dB
I_CL
Output Current
GBP
Gain Bandwidth Product
10
40
mA
2
MHz
SR
V_O(MAX)
R_IN
Slew Rate
Maximum High Output Voltage
Input Resistance
R_L = 2k
I_OUT = 1mA
Measured at IN⁺ Pin
5
V/µs
V_CC – 1.2 V_CC –␣ 0.8
V
80
kΩ
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: T_J is calculated from the ambient temperature T_A and power
dissipation P_D according to the following formula:
LTC3733CG: T_J = T_A + (P_D × 95°C/W)
LTC3733CUHF-1: T_J = T_A + (P_D × 34°C/W)
Note 3: The IC is tested in a feedback loop that includes the differential
amplifier in a unity-gain configuration loaded with 100µA to ground driving
the VID DAC into the error amplifier and servoing the resultant voltage to
the midrange point for the error amplifier (V_ITH = 1.2V).
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
Note 5: The minimum on-time condition corresponds to an inductor peak-
to-peak ripple current of ≥ 40% of I_MAX (see minimum on-time
considerations in the Applications Information Section).
Note 6: ATTEN_ERR specification is in addition to the output voltage
accuracy specified at VID code 10011.
Note 7: This IC includes overtemperature protection that is intended to protect
the device during momentary overload conditions. Junction temperature will
exceed 125°C when overtemperature protection is active. Continuous operation
above the specified maximum operating junction temperature may impair
device reliability.
3733f
4