EVALUATION KIT AVAILABLE
MAX16993
Step-Down Controller with
Dual 2.1MHz Step-Down DC-DC Converters
General Description
The MAX16993 power-management integrated circuit
(PMIC) is a 2.1MHz, multichannel, DC-DC convert-
er designed for automotive applications. The device
integrates three supplies in a small footprint. The device
includes one high-voltage step-down controller (OUT1)
designed to run directly from a car battery and two low-
voltage step-down converters (OUT2/OUT3) cascaded
from OUT1. Under no-load conditions, the MAX16993
consumes only 30µA of quiescent current, making it ideal
for automotive applications.
The high-voltage synchronous step-down DC-DC
controller (OUT1) operates from a voltage up to 36V
continuous and is protected from load-dump transients up
to 42V. There is a pin-selectable frequency option of either
2.1MHz or a factory-set frequency for 1.05MHz, 525kHz,
420kHz, or 350kHz. The low-voltage, synchronous step-
down DC-DC converters run directly from OUT1 and can
supply output currents up to 3A.
The device provides a spread-spectrum enable input
(SSEN) to provide quick improvement in electromagnetic
interference when needed. There is also a SYNC
input for providing an input to synchronize to
an external clock source (see the
Selector Guide).
The device includes overtemperature shutdown and
overcurrent limiting. The device also includes indi-
vidual
RESET_
outputs and individual enable inputs.
The individual
RESET_
outputs provide voltage
monitoring for all output channels.
The MAX16993 is available in a 32-pin TQFN/side-
wettable QFND-EP package and is specified for operation
over the -40°C to +125°C automotive temperature range.
Benefits and Features
●
High-Efficiency Voltage DC-DC Controller Saves
Power
• 3.5V to 36V Operating Supply Voltage
• Output Voltage: Pin Selectable, Fixed, or
Resistor-Divider Adjustable
• 350kHz to 2.1MHz Operation
•
30μA Quiescent Current with DC-DC
Controller Enabled
●
Dual 2.1MHz DC-DC Converters with Integrated
FETs Save Space
• OUT2 and OUT3 are Cascaded from OUT1,
Improving Efficiency
• 3A Integrated FETs
• 0.8V to 3.95V Output Voltage
• Fixed or Resistor-Divider-Adjustable Output Voltage
• 180° Out-of-Phase Operation
• Robust for the Automotive Environment
●
Current-Mode Architecture with Forced-PWM and
Skip Modes of Operation
• Frequency Synchronization Input/Output Reduces
System Noise
• Individual Enable Inputs and
RESET_
Outputs
• Overtemperature and Short-Circuit Protection
•
AECQ-100 Qualified
• 32-Pin TQFN-EP (5mm x 5mm x 0.75mm) and
Side-Wettable QFND-EP (5mm x 5mm x 0.8mm)
• -40°C to +125°C Operating Temperature Range
Applications
● Automotive
● Industrial
Ordering Information
and
Selector Guide
appear at end of
data sheet.
19-6684; Rev 14; 12/16
MAX16993
Step-Down Controller with
Dual 2.1MHz Step-Down DC-DC Converters
Absolute Maximum Ratings
V
SUP
, EN1 to GND ...............................................-0.3V to +45V
PV_ to GND..........................................................-0.3V to +6.0V
PV_ to GND..........................................................-0.3V to +6.0V
PV2 to GND, PV2 to PGND2 ...............................-0.3V to +6.0V
PV3 to GND, PV3 to PGND3 ...............................-0.3V to +6.0V
PGND2–PGND3 to GND......................................-0.3V to +0.3V
LX1 to GND ...............................................-6.0V to V
SUP
+ 6.0V
BST1 to LX1 (Note 1) ...........................................-0.3V to +6.0V
DH1 to LX1 (Note 1)..................................-0.3V to BST1 + 0.3V
BIAS to GND ........................................................-0.3V to +6.0V
DL1 to GND (Note 1)...................................-0.3V to PV1 + 0.3V
LX2 to PGND2.............................................-0.3V to PV2 + 0.3V
LX3 to PGND3.............................................-0.3V to PV3 + 0.3V
OUT1, CS1, OUT2, OUT3 to GND ......................-0.3V to +6.0V
SYNC to GND .............................................-0.3V to PV_ + 0.3V
FB1, EN2, EN3 to GND........................................-0.3V to +6.0V
RESET_, ERR
to GND.........................................-0.3V to +6.0V
CS1 to OUT1 ........................................................-0.3V to +0.3V
CSEL1, SSEN to GND .........................................-0.3V to +6.0V
COMP1 to GND.............................................-0.3V to PV + 0.3V
LX2, LX3 Output Short-Circuit Duration ....................Continuous
Continuous Power Dissipation (T
A
= +70ºC)
Side-Wettable QFND (derate 27mW/ºC above +70ºC)......2160mW
TQFN (derate 34.5mW/ºC above +70ºC)...............2758.6mW
Operating Temperature Range ..........................-40ºC to +125°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65ºC to +150°C
Lead Temperature (soldering, 10s) ................................. +300°C
Soldering Temperature (reflow) .......................................+260°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Package Thermal Characteristics
(Note 2)
Side-Wettable QFND
Junction-to-Ambient Thermal Resistance (θ
JA
) ......... 37°C/W
Junction-to-Case Thermal Resistance (θ
JC
) ............ 2.8°C/W
TQFN
Junction-to-Ambient Thermal Resistance (θ
JA
) ......... 29°C/W
Junction-to-Case Thermal Resistance (θ
JC
) ............ 1.7°C/W
Note 1:
Self-protected against transient voltages exceeding these limits for ≤ 50ns under normal operation and loads up to the
maximum rated output current.
Note 2:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to
www.maximintegrated.com/thermal-tutorial.
Electrical Characteristics
(V
SUP
= 14V, V
PV1
= V
BIAS
, V
PV2
= V
PV3
= V
OUT1
; T
A
= T
J
= -40°C to +125°C, unless otherwise noted. Typical values are at
T
A
= +25°C under normal conditions, unless otherwise noted.) (Note 3)
PARAMETER
Supply Voltage Startup
Threshold
Supply Voltage Range
Supply Current
Oscillator Frequency
SYNC Input Frequency
Range
Spread-Spectrum Range
BIAS Regulator Voltage
PV_ POR
V
BIAS
V
SSEN
= V
GND
V
SSEN
= V
BIAS
6V ≤ V
SUP
≤ 42V, no switchover
V
BIAS
falling
Hysteresis
4.6
2.5
SYMBOL
V
SUP,STARTUP
V
SUP
I
SUP
f
SW
V
SUP
rising
Normal operation, after Buck 1 startup
V
EN1
= V
EN2
= V
EN3
= 0V
V
EN1
= 5V, V
EN2
= V
EN3
= 0V (no load)
2.0
1.7
0
+6
5.0
2.7
0.45
5.4
2.9
CONDITIONS
MIN
4.25
3.5
4
20
2.1
TYP
4.5
MAX
4.75
36
15
40
2.2
2.4
UNITS
V
V
µA
MHz
MHz
%
V
V
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Maxim Integrated
│
2
MAX16993
Step-Down Controller with
Dual 2.1MHz Step-Down DC-DC Converters
Electrical Characteristics (continued)
(V
SUP
= 14V, V
PV1
= V
BIAS
, V
PV2
= V
PV3
= V
OUT1
; T
A
= T
J
= -40°C to +125°C, unless otherwise noted. Typical values are at
T
A
= +25°C under normal conditions, unless otherwise noted.) (Note 3)
PARAMETER
SYMBOL
CONDITIONS
V
CSEL1
= V
GND
V
CSEL1
= V
BIAS
(factory option)
OUT1 Switching Frequency
f
SW1
Internally generated
(see the
Selector
Guide)
V
CSEL1
= V
BIAS
(factory option)
V
CSEL1
= V
BIAS
(factory option)
V
CSEL1
= V
BIAS
(factory option)
V
FB1
= V
GND
Voltage
V
OUT1
Fixed option
(see the
Selector
Guide)
V
FB1
= V
BIAS
(factory option)
V
FB1
= V
BIAS
(factory option)
0.985
300
5.5V ≤ V
SUP
≤ 18V, 0 < V
LIM1
< 75mV,
PWM mode
PWM mode
PWM mode
V
EN1
= V
GND
or V
SUP
V
DH1
rising, I
DH1
= 100mA
V
DH1
falling, I
DH1
= 100mA
V
DL1
rising, I
DL1
= 100mA
V
DL1
falling, I
DL1
= 100mA
V
LIM1
I
SKIP
CSI – OUT1
CS1 – OUT1, no load
100
10
-2.0
0.02
0.03
100
2
1
2.5
1.5
120
35
4
V
LX1
= V
SUP
PWM mode
60
107
110
0.01
97.2
75
113
200
4
4
5
3
150
60
MIN
TYP
2100
1050
525
420
350
3.3
5.0
3.15
1.0
700
1.019
1200
+2.5
V
µS
%
%/A
%/V
Ω
Ω
Ω
mV
mV
ms
µA
%
ns
%
V
kHz
MAX
UNITS
OUT1: HIGH-VOLTAGE SYNCHRONOUS STEP-DOWN DC-DC CONTROLLER
FB1 Regulation Voltage
Error Amplifier
Transconductance
Voltage Accuracy
DC Load Regulation
DC Line Regulation
OUT1 Discharge Resistance
High-Side Output Drive
Resistance
Low-Side Output Drive
Resistance
Output Current-Limit
Threshold
Skip Current Threshold
Soft-Start Ramp Time
LX_ Leakage Current
Duty-Cycle Range
Minimum On-Time
OUT1 OV Threshold
g
MEA
V
OUT1
Adjustable option (see the
Selector Guide)
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Maxim Integrated
│
3
MAX16993
Step-Down Controller with
Dual 2.1MHz Step-Down DC-DC Converters
Electrical Characteristics (continued)
(V
SUP
= 14V, V
PV1
= V
BIAS
, V
PV2
= V
PV3
= V
OUT1
; T
A
= T
J
= -40°C to +125°C, unless otherwise noted. Typical values are at
T
A
= +25°C under normal conditions, unless otherwise noted.) (Note 3)
PARAMETER
Supply Voltage Range
Supply Current
Skip Mode Peak Current
Voltage Accuracy
Feedback-Voltage Accuracy
Load Regulation
LX_ On-Resistance High
LX_ On-Resistance Low
Current-Limit Threshold
LX_ Rise/Fall Time
Soft-Start Ramp Time
LX_ Leakage Current
Duty-Cycle Range
LX_ Discharge Resistance
RESET_
Rising (relative to nominal output voltage)
Falling (relative to nominal output voltage)
See the
Selector Guide
(16,384 clocks)
See the
Selector Guide
(8192 clocks)
See the
Selector Guide
(4096 clocks)
See the
Selector Guide
(256 clocks)
See the
Selector Guide
(16,384 clocks)
OUT2, OUT3 Active
Timeout Period
See the
Selector Guide
(8192 clocks)
See the
Selector Guide
(4096 clocks)
See the
Selector Guide
(256 clocks)
92
90
PWM mode
15
22
95
92
7.8
3.9
ms
1.9
0.1
7.8
3.9
ms
1.9
0.1
I
LMAX
V
OUT
0A ≤ I
LOAD
≤ I
MAX,
PWM mode
Adjustable mode, I
OUT2
= 0mA
0A ≤ I
LOAD
≤ I
MAX
(PWM mode)
0A ≤ I
LOAD
≤ I
MAX
(PWM mode, low gain,
see the
Selector Guide)
I
LX_
= -800mA
I
LX_
= 800mA
I
MAX
= 3.0A option (see the
Selector Guide)
I
MAX
= 1.5A option (see the
Selector Guide)
PV2 = PV3 = 3.3V, I
OUT_
= 2A
5.0
2.5
-3.0
0.806
-1.5
-2.5
0.815
-1.0
-1.7
70
50
5.6
3.0
4
2.5
0.01
100
48
98
95
110
90
%
mΩ
mΩ
A
ns
ms
µA
%
Ω
SYMBOL
V
SUP
I
PV_
V
EN_
= 5V, no load
CONDITIONS
MIN
2.7
0.1
0.2 x I
LMAX
+3.0
0.824
TYP
MAX
5.5
5
UNITS
V
µA
mA
%
V
OUT2 AND OUT3: LOW-VOLTAGE SYNCHRONOUS STEP-DOWN DC-DC CONVERTERS
Reset Threshold
%
OUT1 Active Timeout Period
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Maxim Integrated
│
4
MAX16993
Step-Down Controller with
Dual 2.1MHz Step-Down DC-DC Converters
Electrical Characteristics (continued)
(V
SUP
= 14V, V
PV1
= V
BIAS
, V
PV2
= V
PV3
= V
OUT1
; T
A
= T
J
= -40°C to +125°C, unless otherwise noted. Typical values are at
T
A
= +25°C under normal conditions, unless otherwise noted.) (Note 3)
PARAMETER
Output Low Level
Propagation Time
ERR
Output Low Level
THERMAL OVERLOAD
Thermal-Warning
Temperature
Thermal-Shutdown
Temperature
Thermal-Shutdown
Hysteresis
ENABLE INPUTS (EN_)
Input High
Hysteresis
EN Input Current
SYNCHRONIZATION I/O (SYNC)
Input High
Input Low
Input Current
Pulldown Resistance
LOGIC INPUTS (CSEL1, SSEN)
Input High
Input Low
Input Current
T
A
= +25°C
Note 3:
All units are 100% production tested at TA = +25°C. All temperature limits are guaranteed by design.
1.4
0.5
2
V
V
µA
SYNC input option
(see the
Selector Guide)
SYNC input option
(see the
Selector Guide)
SYNC input option (see the
Selector
Guide);
V
SYNC
= 5V
50
100
1.8
0.8
80
V
V
µA
kΩ
V
EN_
= 5V
0.5
V
EN_
rising
1.6
1.8
0.2
1.0
2.0
2.0
V
V
µA
+150
+170
15
°C
°C
°C
SYMBOL
I
SINK
= 3mA
OUT1, 5% below threshold
OUT2/OUT3, 5% below threshold
I
SINK
= 3mA
5
2
CONDITIONS
MIN
TYP
0.1
10
4
0.1
MAX
0.2
20
8
0.2
UNITS
V
µs
µs
V
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