Rainbow Electronics MAX1855 User Manual
General Description
The MAX1716/MAX1854/MAX1855 step-down controllers are intended for core CPU DC-DC converters in
notebook computers. They feature a dynamically
adjustable output (5-bit DAC), ultra-fast transient
response, high DC accuracy, and high efficiency needed for leading-edge CPU core power supplies. Maxim's
proprietary Quick-PWM™ quick-response, constant-ontime PWM control scheme handles wide input/output
voltage ratios with ease and provides 100ns “instant-on”
response to load transients while maintaining a relatively constant switching frequency.
The MAX1716/MAX1854/MAX1855 are designed
specifically for CPU core applications requiring a voltage-positioned supply. The voltage-positioning input
(VPS), combined with a high DC accuracy control loop,
is used to implement a power supply that modifies its
output set point in response to the load current. This
arrangement decreases full-load power dissipation and
reduces the required number of output capacitors.
The 28V input range of the MAX1716/MAX1854/MAX1855
enables single-stage buck conversion from high-voltage batteries for the maximum possible efficiency.
Alternatively, the devices’ high-frequency capability
combined with two-stage conversion (stepping down
the +5V system supply instead of the battery) allows
the smallest possible physical size. The output voltage
can be dynamically adjusted through the 5-bit digitalto-analog converter (DAC) inputs.
The MAX1716/MAX1854/MAX1855 are available in a
24-pin QSOP package. For applications requiring
SpeedStep™ power control (see the MAX1717).
________________________Applications
Notebook Computers
Docking Stations
CPU Core Supply
Single-Stage (BATT to V
CORE
) Converters
Two-Stage (+5V to V
CORE
) Converters
Features
♦ High-Efficiency Voltage Positioning
♦ Quick-PWM Architecture
♦ ±1% V
OUT
Line-Regulation Accuracy
♦ Adjustable Output Range (5-Bit DAC)
MAX1716: 0.925V to 1.6V
MAX1854: 0.925V to 2.0V
MAX1855: 0.600V to 1.75V
♦ 2V to 28V Input Range
♦ 200/300/400/550kHz Switching Frequency
♦ Output Undervoltage Protection
♦ Overvoltage Protection (MAX1716/MAX1855)
♦ Drive Large Synchronous-Rectifier MOSFETs
♦ 1.7ms Digital Soft-Start
♦ 700µA I
CC
Supply Current
♦ 1µA Shutdown Supply Current
♦ 2V ±1% Reference Output
♦ V
GATE
Transition-Complete Indicator
♦ Small 24-Pin QSOP Package
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
________________________________________________________________ Maxim Integrated Products 1
19-1758; Rev 0; 8/00
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Pin Configuration appears at end of data sheet.
Quick-PWM is a trademark of Maxim Integrated Products.
SpeedStep is a trademark of Intel Corp.
Ordering Information
Typical Operating Circuit
PART TEMP. RANGE PIN-PACKAGE
MAX1716EEG -40°C to +85°C 24 QSOP
MAX1854EEG -40°C to +85°C 24 QSOP
MAX1855EEG -40°C to +85°C 24 QSOP
+5V INPUT
DAC
INPUTS
V
CC
SHDN
ILIM
REF
CC
SKIP
GND
TON
D0
D1
D2
D3
D4
MAX1716
MAX1854
MAX1855
V
BST
VPS
PGND
VGATE
DD
V+
DH
LX
DL
CS
FB
BATTERY
2V TO 28V
OUTPUT
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, V+ = +15V, VCC= VDD= 5V, SKIP = VCC, VPS = PGND, TA= 0°C to +85°C, unless otherwise noted. Typical
values are at T
A
= +25°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.
Note 1: SKIP may be forced below -0.3V, temporarily exceeding the absolute maximum rating, for the purpose of debugging proto-
type breadboards, using the no-fault test mode. Limit the current drawn to -2mA (max).
V+ to GND ..............................................................-0.3V to +30V
V
CC
, VDDto GND .....................................................-0.3V to +6V
PGND to GND.....................................................................±0.3V
SHDN, VGATE to GND .............................................-0.3V to +6V
ILIM, FB, CC, REF, D0–D4, VPS,
TON to GND ...........................................-0.3V to (V
CC
+ 0.3V)
SKIP to GND (Note 1).................................-0.3V to (V
CC
+ 0.3V)
DL to PGND................................................-0.3V to (V
DD
+ 0.3V)
BST to GND ............................................................-0.3V to +36V
DH to LX....................................................-0.3V to (V
BST
+ 0.3V)
LX to BST..................................................................-6V to +0.3V
CS to GND.................................................................-2V to +30V
REF Short Circuit to GND ...........................................Continuous
Continuous Power Dissipation (T
A
= +70°C)
24-Pin QSOP (derate 9.5mW/°C above +70°C)...........762mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PWM CONTROLLER
Input Voltage Range
DC Output Voltage Accuracy
(Notes 2, 3)
FB Input Bias Current I
VPS Input Bias Current I
VPS Gain A
CS Input Bias Current I
ILIM Input Leakage Current I
Soft-Start Ramp Time 0 to full ILIM 1.7 ms
On-Time (Note 4) t
Minimum Off-Time (Note 4) t
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Battery voltage, V+ 2 28
V
, V
CC
DD
V+ = 4.5V to 28V,
VPS = PGND
FB
VPS
VPS
CS
ILIM
ON
OFF( M IN)
FB = 0.6V to 2.0V -0.2 0.2 µA
V
= ±40mV -1 1 µA
VPS
V
= 0 or -40mV, gain from VPS to FB 0.153 0.175 0.197 %/mV
VPS
0 to 28V -1 1 µA
V
= 0 or 5.0V 0.01 100 nA
ILIM
V+ = 11.0V,
V
= 1.5V
FB
DAC codes from
1.35V to 2.0V
DAC codes from
0.925V to 1.3V
DAC codes from
0.6V to 0.9V
TON = GND 205 255 300
TON = REF 280 327 375
TON = open 425 470 520
TON = V
CC
4.5 5.5
-1 1
-1.2 1.2
-1.5 1.5
615 678 740
400 500 ns
V
%
ns
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V+ = +15V, VCC= VDD= 5V, SKIP = VCC, VPS = PGND, TA= 0°C to +85°C, unless otherwise noted. Typical
values are at T
A
= +25°C.)
BIAS AND REFERENCE
Quiescent Supply Current (VCC)I
Quiescent Supply Current (VDD)I
Quiescent Supply Current (V+) I+ 25 40 µA
Shutdown Supply Current (VCC) SHDN = GND <1 5 µA
Shutdown Supply Current (VDD) SHDN = GND <1 5 µA
Shutdown Supply Current (V+) SHDN = GND, VCC = VDD = 0 or 5V <1 5 µA
Reference Voltage V
Reference Load Regulation I
REF Sink Current I
REF Fault Lockout Voltage Falling edge 1.6 V
FAULT PROTECTION
Output Overvoltage Fault
Threshold (Note 5)
Output Overvoltage Fault
Propagation Delay (Note 5)
Output Undervoltage Fault
Threshold (Foldback)
Output Undervoltage Fault
Propagation Delay
Output Undervoltage Fault
Blanking Time (Foldback)
Current-Limit Threshold
(Positive, Default)
Current-Limit Threshold
(Positive, Adjustable)
Negative Current-Limit
Threshold
Zero-Crossing Current-Limit
Threshold
Thermal Shutdown Threshold Hysteresis = 10°C 150 °C
VCC Undervoltage Lockout
Threshold
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
V
V
CC
DD
REF
REF
ITH
ITH
Measured at VCC, FB forced above the
regulation point
Measured at VDD, FB forced above the
regulation point
VCC = 4.5V to 5.5V, no external REF load 1.98 2 2.02 V
= 0 to 50µA 0.01 V
REF
REF in regulation 10 µA
Measured at FB
FB forced to 2% above trip threshold
(MAX1716/MAX1855 only)
FB forced to 2% below trip threshold 10 µs
From SHDN signal going high 10 30 ms
V
- VCS, ILIM = V
PGND
V
- V
PGND
V
PGND
V
PGND
Rising edge, hysteresis = 20mV, switching
disabled below this level
- V
- V
CS
CS
CS
MAX1716 1.8 1.9 2.0
MAX1855 1.97 2.0 2.03
35 40 45 %
CC
V
= 0.5V 40 50 60
ILIM
V
= 2V (REF) 170 200 230
ILIM
110 120 130 mV
4.0 4.45 V
700 950 µA
<1 5 µA
V
1.5 µs
mV
-1.2 ×
V
ITH
3mV
mV
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V+ = +15V, VCC= VDD= 5V, SKIP = VCC, VPS = PGND, TA= 0°C to +85°C, unless otherwise noted. Typical
values are at T
A
= +25°C.)
)
VGATE Lower Trip Threshold
VGATE Upper Trip Threshold
VGATE Propagation Delay
VGATE Output Low Voltage I
VGATE Leakage Current High state, forced to 5.5V 1 µA
GATE DRIVERS
DH Gate Driver On-Resistance R
DL Gate Driver On-Resistance R
DH Gate Driver Source/Sink
Current
DL Gate Drive Sink Current I
DL Gate Driver Source Current I
Dead-Time
LOGIC AND I/O
Logic Input High Voltage V
Logic Input Low Voltage V
TON Input Levels
Logic Input Current
D0−D4 Pullup Current D0−D4 = GND 3 5 10 µA
SKIP No-Fault Mode Current
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Measured at FB with respect to unloaded
output voltage, falling edge
Measured at FB with respect to unloaded
output voltage, rising edge
Falling edge, FB forced 2% below or above
VGATE trip threshold
SINK
ON ( D H ) VBST
ON(DL
I
DH
DL
DL
High state (pullup) 1.5 5
Low state (pulldown) 0.5 1.7
DH forced to 2.5V, V
DL forced to 5V 3 A
DL forced to 2.5V 1 A
DL rising 35
DH rising 26
D0−D4, SHDN, SKIP 2.4 V
IH
D0−D4, SHDN, SKIP 0.8 V
IL
TON = VCC (200kHz operation) VCC - 0.4
TON = open (300kHz operation) 3.15 3.85
TON = REF (400kHz operation) 1.65 2.35
TON = GND (550kHz operation) 0.5
TON = GND or V
SHDN, SKIP = GND or V
T
A
= 1mA 0.4 V
- VLX forced to 5V 1.3 5 Ω
forced to 5V 1 A
- V
BST
LX
CC
CC
= +25°C -1.5 -0.1 mA
-12.5 -10 -7.5 %
7.5 10 12.5 %
1.5 µs
-3 3
-1 1
Ω
ns
V
µA
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
_______________________________________________________________________________________ 5
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, V+ = +15V, VCC= VDD= 5V, SKIP = VCC, VPS = PGND, TA= -40°C to +85°C, unless otherwise noted.) (Note 6)
PWM CONTROLLER
Input Voltage Range
DC Output Voltage Accuracy
(Notes 2, 3)
FB Input Bias Current I
VPS Input Bias Current I
VPS Gain A
CS Input Bias Current I
ILIM Input Leakage Current I
On-Time (Note 4) t
Minimum Off-Time (Note 4) t
BIAS AND REFERENCE
Quiescent Supply Current (VCC)I
Quiescent Supply Current (VDD)I
Quiescent Supply Current (V+) I+ 40 µA
Shutdown Supply Current (VCC) SHDN = GND 5 µA
Shutdown Supply Current (VDD) SHDN = GND 5 µA
Shutdown Supply Current (V+) S HDN = GN D , V + = 28V , V
Reference Voltage V
Reference Load Regulation I
REF Sink Current I
FAULT PROTECTION
Output Overvoltage Fault
Threshold (Note 5)
Output Undervoltage Fault
Threshold (Foldback)
Output Undervoltage Fault
Blanking Time (Foldback)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
FB
VPS
VPS
CS
ILIM
ON
OFF( M IN)
CC
DD
REF
REF
Battery voltage, V+ 2 28
, V
V
CC
DD
DAC codes from
V+ = 4.5V to 28V,
VPS = PGND
FB = 0.6V to 2.0V -0.2 0.2 µA
V
= ±40mV -1 1 µA
VPS
V
= 0 or -40mV, gain from VPS to FB 0.153 0.197 %/mV
VPS
0 to 28V -1 1 µA
V
= 0 or 5.0V 100 nA
ILIM
V+ = 11.0V,
V
= 1.5V
FB
Measured at VCC, FB forced above the
regulation point
Measured at VDD, FB forced above the
regulation point
VCC = 4.5V to 5.5V, no external REF load 1.98 2.02 V
= 0 to 50µA 0.01 V
REF
REF in regulation 10 µA
Measured at FB
From SHDN signal going high 10 30 ms
1.35V to 2.0V
DAC codes from
0.6V to 1.3V
TON = GND 205 300
TON = REF 280 375
TON = open 425 520
TON = V
MAX1716 1.8 2.0 V
MAX1855 1.97 2.03
C C
CC
= V
= 0 or 5V 5 µA
D D
4.5 5.5
-1.6 1.6
-2 2
615 740
500 ns
950 µA
5 µA
35 45 %
V
%
ns
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
6 _______________________________________________________________________________________
Note 2: Output voltage accuracy specifications apply to DAC voltages from 0.6V to 2.0V. Includes load-regulation error.
Note 3: When the inductor is in continuous conduction, the output voltage will have a DC regulation level higher than the error-com-
parator threshold by 50% of the ripple. In discontinuous conduction (SKIP = GND, light load), the output voltage will have a
DC regulation level higher than the trip level by approximately 1.5% due to slope compensation.
Note 4: On-time and off-time specifications are measured from 50% to 50% at the DH pin, with LX forced to 0, BST forced to 5V, and
a 500pF capacitor from DH to LX to simulate external MOSFET gate capacitance. Actual in-circuit times may be different
due to MOSFET switching speeds.
Note 5: The MAX1854 does not have overvoltage protection.
Note 6: Specifications to -40°C are guaranteed by design, not production tested.
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V+ = +15V, VCC= VDD= 5V, SKIP = VCC, VPS = PGND, TA= -40°C to +85°C, unless otherwise noted.) (Note 6)
)
Current-Limit Threshold
(Positive, Default)
Current-Limit Threshold
(Positive, Adjustable)
VCC Undervoltage Lockout
Threshold
VGATE Lower Trip Threshold
VGATE Upper Trip Threshold
VGATE Output Low Voltage I
VGATE Leakage Current High state, forced to 5.5V 1 µA
GATE DRIVERS
DH Gate Driver On-Resistance R
DL Gate Driver On-Resistance R
LOGIC AND I/O
Logic Input High Voltage V
Logic Input Low Voltage V
TON Input Levels
Logic Input Current
D0−D4 Pullup Current D0−D4 = GND 3 10 µA
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
V
ITH
V
ITH
ON ( D H ) VBST
ON(DL
IH
V
- VCS, ILIM = V
PGND
V
- V
PGND
Rising edge, hysteresis = 20mV, switching
disabled below this level
Measured at FB with respect to unloaded
output voltage, falling edge
Measured at FB with respect to unloaded
output voltage, rising edge
SINK
High state (pullup) 5
Low state (pulldown) 1.7
D0−D4, SHDN, SKIP 2.4 V
D0−D4, SHDN, SKIP 0.8 V
IL
TON = VCC (200kHz operation) VCC - 0.4
TON = open (300kHz operation) 3.15 3.85
TON = REF (400kHz operation) 1.65 2.35
TON = GND (550kHz operation) 0.5
TON = GND or V
SHDN, SKIP = GND or V
CS
= 1mA 0.4 V
- VLX forced to 5V 5 Ω
CC
CC
V
= 0.5V 35 65
ILIM
V
= 2V (REF) 160 240
ILIM
CC
100 140 mV
4.0 4.45 V
-12.5 -7.5 %
7.5 12.5 %
-3 3
-1 1
mV
Ω
V
µA
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
_______________________________________________________________________________________ 7
Typical Operating Characteristics
(Circuit from Figure 1, components from Table 2, TA = +25°C, unless otherwise noted.)
EFFICIENCY vs. LOAD CURRENT
(2.0V AT 300kHz)
A1
C1
D1
A2
B2
LOAD CURRENT (A)
B1
C2
D2
MAX1854 ONLY
EFFICIENCY vs.
LOAD CURRENT (1.3V AT 300kHz)
C1
B1
A1
D1
A2
B2
LOAD CURRENT (A)
C2
D2
CIRCUIT #2
L = 1.0µH
EFFECTIVE EFFICIENCY vs.
LOAD CURRENT (1.3V AT 300kHz)
C1
B1
A1
D1
A2
C2B2
D2
CIRCUIT #2
L = 1.0µH
LOAD CURRENT (A)
SKIP MODE (SKIP = GND)
A1: V
= 4.5V
BATT
= 7V
B1: V
BATT
= 15V
C1: V
BATT
= 24V
D1: V
BATT
PWM MODE (SKIP = V
A2: V
= 4.5V
BATT
= 7V
B2: V
BATT
= 15V
C2: V
BATT
= 24V
D2: V
BATT
)
CC
EFFICIENCY vs.
LOAD CURRENT (1.3V AT 200kHz)
100
95
90
A1
85
80
75
70
EFFICIENCY (%)
65
60
55
50
0.01 0.1 1 10 100
B1
D1
A2
B2
C1
C2
D2
LOAD CURRENT (A)
EFFECTIVE EFFICIENCY vs.
LOAD CURRENT (1.3V AT 200kHz)
100
95
A1
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
0.01 0.1 1 10 100
B1
D1
A2
B2
C1
C2
D2
LOAD CURRENT (A)
CIRCUIT #2
L = 1.5µH
CIRCUIT #2
L = 1.5µH
MAX1716-03
MAX1716-06
100
95
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
0.01 10.1 1 10 100
100
95
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
0.01 0.1 1 10 100
100
95
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
0.01 0.1 1 10 100
MAX1716-01
MAX1716-04
MAX1716-07
EFFICIENCY vs. LOAD CURRENT
(1.6V AT 300kHz)
100
95
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
B1
A1
0.01 10.1 1 10 100
C1
D1
A2
B2
LOAD CURRENT (A)
C2
D2
EFFICIENCY vs.
LOAD CURRENT (1.3V AT 550kHz)
100
95
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
0.01 0.1 1 10 100
A1
D1
C1
B1
A2
B2
LOAD CURRENT (A)
C2
CIRCUIT #2
D2
L = 0.68µH
EFFECTIVE EFFICIENCY vs.
LOAD CURRENT (1.3V AT 550kHz)
100
95
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
B1
A1
D1
0.01 0.1 1 10 100
C1
A2
B2
LOAD CURRENT (A)
C2
D2
CIRCUIT #2
L = 0.68µH
MAX1716-02
MAX1716-05
MAX1716-08
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
8 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(Circuit from Figure 1, components from Table 2, TA = +25°C, unless otherwise noted.)
EFFICIENCY vs.
LOAD CURRENT (1.0V AT 400kHz)
100
95
90
85
80
75
70
EFFICIENCY (%)
65
60
55
50
0.01 0.1 1 10 100
B1
A1
D1
C1
A2
LOAD CURRENT (A)
B2
C2
D2
CIRCUIT #3
1.64
1.62
MAX1716-09
1.60
1.58
1.56
OUTPUT VOLTAGE (V)
1.54
1.52
1.50
OUTPUT VOLTAGE vs. LOAD CURRENT
(1.6V AT 300kHz)
PWM MODE
SKIP MODE
V
= 24V
BATT
V
= 7V
BATT
010515
LOAD CURRENT (A)
20 25
1.34
MAX1716-10
1.32
1.30
1.28
1.26
OUTPUT VOTLAGE (V)
1.24
1.22
1.20
OUTPUT VOLTAGE vs.
LOAD CURRENT (1.3V AT 300kHz)
PWM MODE
SKIP MODE
V
= 24V
BATT
V
= 7V
BATT
CIRCUIT #2
L = 1.0µH
0462 8 10 12 14
LOAD CURRENT (A)
MAX1716-11
OUTPUT VOLTAGE vs.
LOAD CURRENT (1.0V AT 400kHz)
1.02
1.00
0.98
0.96
OUTPUT VOTLAGE (V)
0.94
CIRCUIT #3
0.92
0462 8 10 12 14
V
= 7V
BATT
V
= 24V
BATT
LOAD CURRENT (A)
PWM MODE
SKIP MODE
MAX1716-12
350
300
250
200
150
FREQUENCY (kHz)
100
50
0
SWITCHING FREQUENCY
vs. LOAD CURRENT
PWM MODE
SKIP MODE
V
OUT(PROG)
084 121620
LOAD CURRENT (A)
SWITCHING FREQUENCY
vs. TEMPERATURE
330
I
= 12A
320
310
300
290
SWITCHING FREQUENCY (kHz)
280
270
-40 10-15 356085
OUT
I
= 5A
OUT
I
OUT
TEMPERATURE (°C)
= 1A
MAX1716-15
0.88
0.86
0.84
0.82
0.80
ON-TIME (µs)
0.78
0.76
0.74
ON-TIME vs. TEMPERATURE
I
= 1A
OUT
I
= 5A
OUT
-40 10-15 35 60 85
TEMPERATURE (°C)
SWITCHING FREQUENCY
vs. BATTERY VOLTAGE
320
MAX1716-13
310
300
290
280
FREQUENCY (kHz)
V
= 7V
BATT
= 1.6V
270
260
V
OUT(PROG)
I
= 12A
OUT
08124 162024
V
OUT(PROG)
= 0.925V
V
BATT
= 1.6V
(V)
MAX1716 -14
NORMALIZED CURRENT-LIMIT ERROR
vs. TEMPERATURE
6
MAX1716-16
I
= 12A
OUT
4
2
0
-2
CURRENT-LIMIT ERROR (%)
-4
-6
-40 10-15 356085
TEMPERATURE (°C)
MAX1716-17
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
_______________________________________________________________________________________ 9
Typical Operating Characteristics (continued)
(Circuit from Figure 1, components from Table 2, TA = +25°C, unless otherwise noted.)
CURRENT-LIMIT ERROR vs. V
3
2
1
0
ERROR (%)
-1
-2
-3
0 1.0 1.50.5 2.0 2.5 3.0
(V)
V
ILIM
ILIM
MAX1716-18
NO-LOAD SUPPLY CURRENT
vs. BATTERY VOLTAGE
0.8
0.7
ICC + I
DD
MAX1716-21
0.6
0.5
0.4
CURCUIT#2 (L = 0.68µH)
SKIP MODE
550kHz (TON = GND)
0.3
SUPPLY CURRENT (mA)
0.2
0.1
I
BATT
0
084 12162024
V
(V)
BATT
LOAD-TRANSIENT RESPONSE
= 15V, PWM MODE)
(V
BATT
CONTINUOUS-TO-DISCONTINUOUS
INDUCTOR CURRENT POINT
4.5
4.0
3.5
3.0
2.5
2.0
1.5
OUTPUT CURRENT (A)
1.0
0.5
0
084 12162024
V
BATT
CIRCUIT#1
= 1.6V
V
OUT
(V)
CIRCUIT#2
= 1.3V
V
OUT
CIRCUIT#3
= 1.0V
V
OUT
NO-LOAD SUPPLY CURRENT
vs. BATTERY VOLTAGE
30
25
20
15
I
10
SUPPLY CURRENT (mA)
BATT
5
0
084 12162024
V
BATT
ICC + I
PWM MODE
550kHz (TON = GND)
CURCUIT#2 (L = 0.68µH)
(V)
DD
WITH DISABLED VOLTAGE POSITIONING
INDUCTOR CURRENT PEAKS AND
VALLEYS vs. BATTERY VOLTAGE
25
MAX1716-19
20
15
10
INDUCTOR CURRENT (A)
5
0
084 121620
NO-LOAD SUPPLY CURRENT
vs. BATTERY VOLTAGE
14
MAX1716-22
12
10
8
6
SUPPLY CURRENT (mA)
4
2
0
084 12162024
LOAD-TRANSIENT RESPONSE
I
PEAK
I
VALLEY
V
= 1.3V
OUT
CIRCUIT#2 (L = 1µH)
V
(V)
BATT
200kHz (TON = V
CURCUIT#2 (L = 1.5µH)
V
(V)
BATT
ICC + I
I
BATT
PWM MODE
MAX1716-20
24
MAX1716-23
DD
)
CC
1.60V
1.55V
1.50V
20A
10A
0
= 1.6V, 50mV/div; B. I
A. V
OUT
CIRCUIT #1, V
= 15V, PWM MODE
BATT
40µs/div
= 1.3A TO 18A, 10A/div;
OUT
MAX1716-24
A
B
1.60V
1.55V
1.50V
20A
10A
0
= 1.6V, 50mV/div; B. I
A. V
OUT
CIRCUIT #1, V
40µs/div
= 0.3A TO 18A, 10A/div;
OUT
= 15V, PWM MODE; VPS = PGND
BATT
MAX1716-25
A
B
MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
10 ______________________________________________________________________________________
Typical Operating Characteristics (continued)
(Circuit from Figure 1, components from Table 2, TA = +25°C, unless otherwise noted.)
B
10A
0
20A
1.55V
1.60V
1.50V
A
40µs/div
A. V
OUT
= 1.6V, 50mV/div; B. I
OUT
= 0.3A TO 18A, 10A/div
CIRCUIT #1, V
BATT
= 15V, SKIP MODE
LOAD-TRANSIENT RESPONSE
(V
BATT
= 15V, SKIP MODE)
MAX1716-26
LOAD-TRANSIENT RESPONSE
= 4.5V)
(V
BATT
1.60V
1.55V
1.50V
20A
10A
LOAD-TRANSIENT RESPONSE
(V
OUT(PROG)
1.00V
0.98V
0.96V
0.94V
20A
10A
0
= 1.0V)
MAX1716-28
A
B
1.65V
1.60V
1.55V
1.50V
20A
10A
0
40µs/div
= 1.6V, 50mV/div
A. V
OUT
= 0.3A TO 18A, 10A/div
B. I
OUT
CIRCUIT #1, V
= 4.5V, PWM MODE
BATT
LOAD-TRANSIENT RESPONSE
WITH CERAMIC OUTPUT CAPACITORS
0
MAX1716-27
A
B
MAX1716-29
A
B
40µs/div
= 1.0V, 20mV/div
A. V
OUT
= 0.3A TO 12A, 10A/div
B. I
OUT
CIRCUIT #3, V
= 4.5V, PWM MODE
BATT
A. V
B. I
CIRCUIT #4, V
40µs/div
= 1.6V, 50mV/div
OUT
= 0.3A TO 18A, 10A/div
OUT
= 15V, PWM MODE
BATT
Loading...