MAX1980ETP+T Maxim Integrated Products, MAX1980ETP+T Datasheet - Page 11

• Manufacturer Part Number: MAX1980ETP+T
• Description: IC CNTRLR QUICK-PWM 20-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX1980ETP+T

• Pwm Type: Controller
• Number Of Outputs: 1
• Frequency - Max: 550kHz
• Duty Cycle: 50%
• Voltage - Supply: 4 V ~ 28 V
• Buck: Yes
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Operating Temperature: 0°C ~ 85°C
• Package / Case: 20-TQFN Exposed Pad
• Frequency-max: 550kHz
• Input Voltage: 4 V to 28 V
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 100 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table 1. Component Selection for Standard
Applications
Output Voltage
Input Voltage Range
Maximum Load Current
Inductor (each phase)
Frequency
High-Side MOSFET
(N
Low-Side MOSFET
(N
Input Capacitor (C
Output Capacitor (C
Current-Sense Resistors
(R
Voltage Positioning Gain
(A
H
L
CS
VPS
PIN
, each phase)
Driver Disable for Multiphase DC-DC Converter
, each phase)
17
18
19
20
and R
)
COMPONENT
CM
)
NAME
LIMIT
TRIG
ILIM
V+
IN
______________________________________________________________________________________
OUT
)
)
Battery Voltage Sense Connection. Connect V+ to the input power source. V+ is used only for PWM one-
shot timing (see the On-Time Control and Active Current Balancing section).
Open-Drain Current-Limit Output. Connect to the master controller’s adjustable current-limit input (ILIM)
according to the Standard Application Circuit (Figure 1). When the voltage across the master controller’s
current-sense resistor (V
LIMIT low.
Dual-Mode Current-Limit Adjustment and Standby Input. The current-limit threshold voltage is 1/10 the
voltage seen at ILIM (V
controller enters a low-power standby mode, forcing DL low and DH low.
Trigger Input. Connect to the master controller’s low-side gate driver. The trigger input’s polarity is pin
selectable: POL = V
triggers on the falling edge (in-phase operation).
Panasonic ETQP6F0R6BFA
Sumida CDEP134H-0R6 or
Panasonic EEFUE0E271R
Fairchild (3) FDS7764A or
CIRCUIT OF FIGURE 1
TDK C4532X5R1E106M
300kHz (TON = float)
International Rectifier
International Rectifier
TMK432BJ106KM or
(8) 270µF, 2.0V
(2) IRF7822 or
(2) IRF7811W
(6) 10µF, 25V
0.6V to 1.75V
Taiyo Yuden
Quick-PWM Slave Controller with
7V to 24V
1.5mΩ
0.6µH
40A
CC
1
ILIM
or floating triggers on the rising edge (out-of-phase operation), and POL = GND
CM+
) over a 400mV to 1.5V range. If V
- V
CM-
) exceeds the current-limit threshold (V
The MAX1980 step-down slave controller is intended for
low-voltage, high-current, multiphase DC-DC applica-
tions. The MAX1980 slave controller can be combined
with any of Maxim’s Quick-PWM step-down controllers to
form a multiphase DC-DC converter. When compared to
single-phase operation, multiphase conversion lowers the
peak inductor current by distributing the load current
between parallel power paths. This simplifies component
selection, power distribution to the load, and thermal lay-
out. Existing Quick-PWM controllers, such as the
MAX1718, function as the master controller, providing
accurate output-voltage regulation, fast transient
response, and multiple fault-protection features.
Synchronized to the master’s low-side gate driver, the
MAX1980 includes a constant on-time controller, syn-
chronous rectifier gate drive, active current balancing,
and precision current-limit circuitry.
The MAX1980 slave controller uses a constant on-time,
voltage feed-forward architecture similar to Maxim’s
Quick-PWM controllers (Figure 2). The control algorithm
is simple: the high-side switch on-time is determined
solely by a one-shot whose period is inversely propor-
tional to input voltage and directly proportional to the
compensation voltage (V
minimum off-time (130ns typical). The on-time one-shot
is triggered when the following conditions are satisfied:
The slave detects a transition on the TRIG input, the
slave controller’s inductor current is below its current-
limit threshold, and the minimum off time has expired.
DESCRIPTION
Pin Description (continued)
ILIM
drops below 250mV, the slave
On-Time Control and Active
Detailed Description
COMP
ILIM
). Another one-shot sets a
/10), the MAX1980 pulls
Current Balancing
11