AP3591

A Product Line of
Diodes Incorporated
AP3591
SINGLE PHASE SYNCHRONOUS BUCK CONTROLLER
Description
Pin Assignments
(Top View)
TON
1
14
2
13 UGATE
VOUT 3
4
FB
5
PGOOD
EP
12
PHASE
11
CS
10 VDDP
6
9 LGATE
7
8
PGND
The operation mode is selectable by EN voltage. A Diode Emulation
Mode (DEM) is activated for increasing efficiency at light loads, while
PWM mode is activated only for low noise operation. The AP3591
also integrates internal Soft-start, UVLO, OVP, OTP, and
programmable OCP to protect the circuit. A Power Good signal is
employed to monitor the output voltage.
VDD
GND
NEW PRODUCT
The constant-on-time PWM control scheme handles wide input/output
voltage ratios with ease and features small external component count
and fast transient response.
BOOT
Pin 1 Mark
EN/DEM
The AP3591 is a synchronous adaptive on-time buck controller
providing high efficiency, excellent transient response and high DC
output accuracy for low voltage regulation in notebook application.
U-QFN3535-14
The AP3591 is available in U-QFN3535-14 package.
Features
Applications

Fixed Frequency Constant On-time Control; Resistor
Programmable Frequency Adjustable from 100kHz to 700kHz

Notebook Computer, AIO PC

Low-voltage Distribute Power

Good Stability Independent of the Output Capacitor ESR

I/O Supplies

Quick Load Step Response

Input Voltage Range: 4.5V to 26V

Output Voltage Range: 0.75V to 5.5V

CCM/DEM Mode Selection

Integrated Bootstrap Diode

Resistor Programmable Current Limit by Low-side RDS_ON
Sense

Integrated Negative Over Current Limit

Integrated OVP/UVP and Over Thermal Shutdown Function

Power Good Indicator

Internal Soft-start

Integrate Output Discharge (Soft-stop)

Safe Start-up into Pre-biased Loads

Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)

Halogen and Antimony Free. “Green” Device (Note 3)
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
Typical Applications Circuit
R3
14
2
10
UGATE
R1
10
4
VDD
C2
1 mF
6
CCM/ DEM
1
5
PGOOD
AP3591
NEW PRODUCT
VDDP
R2
100K
C1
10 mF
BOOT
TON
VDDP
V IN =12V
250K
EN/DEM
PHASE
13
C3
0.1mF
L
12
LGATE
VOUT =1.05V
1.0 mH
9
Q2
8
PGND
C4
220mF
11
CS
R4
3
FB
Q1
VOUT
18K
GND
R6
30K
C
R5
12K
7
Optional
BOM
Symbol
Value
Description
Manufacturer
Part Number
C1
10µF/25V
ESR < 4mΩ @400kHz
Murata
GRM31CR61E106KA12
C4
220µF/6.3V
ESR < 9mΩ @300kHz
Sanyo
6SVPE220M
L
1.0µH
DCR < 4mΩ, IMAX = 24A
Vishay
IHLP5050CEER1R0M01
Q1
N-MOSFET
IDMAX = 30A, RDS(ON) =
Infineon
BSC119N03S
Q2
N-MOSFET
IDMAX = 30A, RDS(ON) =
Infineon
BSC119N03S
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
Pin Descriptions
Pin Name
Function
1
EN/DEM
Enable/Diode Emulation Mode control input. Connect to VDD for DEM mode;
connect to GND for shutdown and float the pin for CCM mode
2
TON
On time/Frequency adjustment pin. Connect to PHASE through a resistor. TON
is an input for the PWM controller
3
VOUT
Output voltage pin. Connect to the output of PWM converter. VOUT is an input
for the PWM controller
4
VDD
Analog supply voltage input for the internal analog integrated circuit. Bypass to
GND with a 1µF ceramic capacitor
5
FB
Feedback input pin. Connect FB pin to a resistor voltage divider from VOUT to
GND to adjust VOUT from 0.75V to 3.3V
6
PGOOD
Power good signal open-drain output for PWM converter. This pin will be pulled
high when the output voltage is within the target range
7
GND
Analog Ground
8
PGND
Power Ground
9
LGATE
Low-side N-MOSFET gate driver output for the PWM converter. This pin swings
between PGND and VDDP
10
VDDP
VDDP is the gate driver supply for external MOSFETs. Bypass to GND with a
1µF ceramic capacitor
11
CS
Over current trip point set input. Connect a resistor from this pin to signal ground
to set threshold for both over current limit and negative over current limit
12
PHASE
The UGATE High-side gate driver return. Also serves as anode of over current
comparator
13
UGATE
High-side N-MOSFET floating gate driver output for the PWM converter. This pin
swings between PHASE and BOOT
14
BOOT
Bootstrap pin. A bootstrap capacitor is connected for PWM converter. Connect
to an external ceramic capacitor to PHASE
–
Exposed Pad
The exposed pad must be soldered to a large PCB and connected to GND for
maximum power dissipation
NEW PRODUCT
Pin Number
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
Functional Block Diagram
TRIG
NEW PRODUCT
VOUT
TON
On-time
Compute
1-SHOT
3
2
SS
(internal)
14
GM
S
VREF
Q
DRV
OV
70% VREF
UV
5
Q
10
DRV
Q
9
8
6
Diode
Emulation
90% VREF
VDD
4
SS Timer
GM
7
1
AP3591
Document number: DS36906 Rev. 1 - 2
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VDDP
LGATE
PGND
PGOOD
10mA
11
Thermal
Shutdown
EN/DEM
PHASE
TRIG
Latch
S1
UGATE
1-SHOT
Latch
S1
125% VREF
13
12
Min. tOFF
Q
FB
BOOT
R
CS
GND
March 2014
© Diodes Incorporated
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AP3591
Absolute Maximum Ratings (Note 4)
Symbol
Parameter
VDD, VDDP
NEW PRODUCT
Unit
-0.3 to 6
V
-0.3 to VPHASE+6
V
Supply Voltage
VBS
BOOT Pin Voltage
VUGATE
Voltage from UGATE to PHASE
-0.3 to 6
V
VLGATE
Voltage from LGATE to GND
-0.3 to 6
V
VPHASE
Voltage from PHASE to GND
-0.3 to 36
V
VPGND
Voltage from PGND to GND
-0.3 to 0.3
V
-0.3 to 6
V
60
C/W
+150
C
-65 to +150
C
–
Note 4:
Rating
Voltage from Other Pins to GND
JA
Thermal Resistance (Junction to Ambient)
TJ
Operating Junction Temperature
TSTG
Storage Temperature
TLEAD
Lead Temperature (Soldering, 10Secs)
+260
C
VHBM
ESD (Human Body Model)
2000
V
VMM
ESD (Machine Model)
200
V
Stresses greater than 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 under “Recommended Operating Conditions” is not implied.
Exposure to “Absolute Maximum Ratings” for extended periods may affect device reliability.
Recommended Operating Conditions
Symbol
VDD, VDDP
VIN
VOUT(MAX)
TA
Parameter
Min
Max
Unit
Supply Voltage
4.5
5.5
V
Input Voltage
4.5
26
V
–
5.5
V
-40
+85
ºC
Maximum Output Voltage
Operating Ambient Temperature
AP3591
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AP3591
Electrical Characteristics (VIN = 12V, VDD = VDDP = 5V, VOUT = 1.05V, TA = +25oC, unless otherwise specified.)
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
4.5
–
26
V
–
500
800
µA
VDD+VDDP current, DEM,
VEN = 5V, VFB = 0.8V
–
500
800
µA
VDD+VDDP current, DEM,
VEN = 0V
–
1
10
µA
VPHASE = 12V, VOUT =
2.5V, RON = 200kΩ
510
630
750
VPHASE = 12V, VOUT =
1.05V, RON = 200kΩ
190
260
330
Min Off Time
–
250
400
580
ns
Internal Soft Start Time
–
0.82
1.2
1.5
ms
–
3.3
7
Ω
–
1
3
Ω
–
1.8
4
Ω
–
0.5
2
Ω
SUPPLY INPUT
NEW PRODUCT
VIN
–
Input Voltage
VDD+VDDP current,
CCM, EN floating, VFB =
IQ-CCM
0.8V
Quiescent Current
IQ-DEM
ISHDN
Shutdown Current
ON-TIME TIMER, OSCILLATOR FREQUENCY AND SOFT START
tON
tOFF-MIN
tSS
On Time
ns
PWM CONTROLLER GATE DRIVERS
RU_PH
RU_GATE
RL_PH
RL_GATE
Upper Gate Pull-up Resistance
Upper Gate Sink Resistance
Lower Gate Pull-up Resistance
Lower Gate Sink Resistance
VBOOT-VPHASE = 5V,
50mA source current
VBOOT-VPHASE = 5V,
50mA sink current
–
VBOOT-VPHASE = 5V,
50mA source current
–
PHASE Falling to LGATE
Rising Delay
VPHASE < 1.2V to
VLGATE > 1.2V
–
30
–
ns
–
LGATE Falling to UGATE
Rising Delay
VLGATE < 1.2V to
(VUGATE-VPHASE) > 1.2V
–
30
–
ns
0.5
0.83
1
V
–
0.1
1
µA
PGOOD from low to high
92.5
95
97.5
%
PGOOD from high to low
102
105
107
%
VBOOT
Boot Diode Forward Voltage
IBSLK
VBS Leakage Current
VDDP-VBOOT, IBOOT =
10mA
VBOOT = 34V, VPHASE =
28V
POWER GOOD
–
PGOOD Threshold
–
–
VPG_L
IPG_LEAK
tDELAY
AP3591
Document number: DS36906 Rev. 1 - 2
PGOOD Lower Threshold
Hysteresis
–
–
±5
–
%
PGOOD Low Voltage
–
–
–
0.4
V
PGOOD Output Leakage
Current
VPGOOD = 5V
–
–
1
µA
PGOOD Delay Time
Delay for PGOOD pin
16
22
36
µs
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AP3591
Electrical Characteristics
(Cont. VIN = 12V, VDD = VDDP = 5V, VOUT = 1.05V, TA = +25oC, unless otherwise specified.)
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
0.75
–
5.5
V
–
20
–
Ω
0.742
0.75
0.758
V
VOUT AND REFERENCE VOLTAGE
Output Voltage
–
Output Discharge Resistance
VEN = 0V
VFB
Feedback Voltage
VDD = 4.5V to 5.5V
IFB
Feedback Bias Current
VFB = 0.75V
-1
–
1
µA
IOC
Current Limit Source Current
CS to GND
9
10
11
µA
–
IOC Temperature Coefficient
–
–
4500
–
ppm/oC
VILIM_SET
Current Limit Setting Voltage
Range
CS to GND
30
–
200
mV
VOCL_OFFSET
Over Current Limit Comparator
Offset Voltage
VCS = 60mV,
VCS-GND-VPGND-PHASE
-10
0
10
mV
VZC_OFFSET
Zero Crossing Comparator
Offset Voltage
VPHASE to GND, VEN =
-10
0
10
mV
VUCL_OFFSET
Negative Over Current Limit
Comparator Offset Voltage
EN floating, VCS = 60mV,
VCS-GND-VPHASE-PGND
-10
0
10
mV
Feedback Over Voltage
Threshold
–
120
125
130
%
Feedback Over Voltage Delay
Time
–
–
33
–
µs
VFBUV /VFB
Feedback Under Voltage
Threshold
–
65
70
75
%
tFBUV_D
Feedback Under Voltage
Protection Delay Time
–
–
28
–
µs
Feedback Under Voltage
Protection Enable Delay Time
–
1.3
2
3.1
ms
VDD Rising
3.7
3.9
4.1
V
–
–
300
–
mV
VOUT
NEW PRODUCT
RDISCHARGE
PROTECTION
VFBOV /VFB
tFBOV_D
tFBUV_EN_D
VUVLO
VHYS
5V
VDD Under Voltage Lock
Threshold
VDD Under Voltage Lock
Hysteresis
TOTSD
Thermal Shutdown
–
–
+160
–
o
THYS
Thermal Shutdown Hysteresis
–
–
+20
–
o
2.4
2.65
2.9
V
–
25
–
mV
Setting PWM-only mode
1.9
1.96
2
V
Shutdown Threshold
0.8
1.24
1.6
V
Hysteresis
–
65
–
mV
VEN = 0V
–
1
–
µA
C
C
LOGIC THRESHOLD
VENH
Setting DEM mode
VENH-HYS
VEN_FT
Hysteresis
EN Control Logic Input Voltage
VENL
VENL-HYS
IEN_PH
AP3591
Document number: DS36906 Rev. 1 - 2
EN Pull_up Current
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AP3591
Performance Characteristics
100
80
80
60
60
40
Efficiency (%)
Efficiency (%)
Efficiency vs. Load Current @VOUT = 2.5V
100
VIN = 8V
VIN = 12V
VIN = 20V
20
VIN = 8V
VIN = 12V
VIN = 20V
40
20
0
0
0
2000
4000
6000
8000
10000
0
12000
2000
4000
6000
8000
10000
12000
Load Current (mA)
Load Current (mA)
Efficiency vs. Load Current (CCM vs. DEM)
Frequency vs. RT
100
1100
1000
80
900
60
40
Frequency (KHz)
Efficiency (%)
800
DEM
CCM
20
VOUT = 1.05V
VOUT = 2.5V
700
600
500
400
300
200
0
100
0
0
2000
4000
6000
8000
10000
12000
0
100
200
Frequency vs. Load Current
400
500
600
700
800
900
Frequency vs. VIN
400
350
350
300
300
Frequency (KHz)
400
250
VIN = 8V
VIN = 12V
VIN = 20V
200
300
RT ()
Load Current (mA)
Frequency (KHz)
NEW PRODUCT
Efficiency vs. Load Current @VOUT = 1.05V
VOUT = [email protected]
VOUT = [email protected]
VOUT = [email protected]
VOUT = [email protected]
250
200
150
150
100
100
-2
0
2
4
6
8
10
12
14
5
16
AP3591
Document number: DS36906 Rev. 1 - 2
10
15
20
25
30
VIN (V)
Load Current (A)
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AP3591
Performance Characteristics (Cont.)
Shutdown Current vs. VIN
ICS vs. Temperature (C)
15
2.0
14
12
ICS (mA)
Shutdown Current (mA)
NEW PRODUCT
13
1.5
1.0
0.5
11
10
9
8
0.0
6
8
10
12
14
16
18
20
22
24
7
-40
26
0
20
40
60
80
100
120
140
160
Temperature ( C)
Power ON from EN @CCM
VOUT
2V/div
-20
o
VIN (V)
Power ON from EN @DEM
VOUT
2V/div
VPHASE
10V/div
VPHASE
10V/div
VEN
1V/div
VEN
2V/div
IL
5A/div
IL
2.5A/div
Time 1ms/div
Time 2ms/div
Power ON from VDD @CCM
Power ON from VDD @DEM
VOUT
2V/div
VOUT
2V/div
VPHASE
10V/div
VPHASE
10V/div
VDD
1V/div
VDD
2V/div
IL
5A/div
IL
5A/div
Time 1ms/div
AP3591
Document number: DS36906 Rev. 1 - 2
Time 1ms/div
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AP3591
Performance Characteristics (Cont.)
OVP
UVP
NEW PRODUCT
VOUT
2V/div
VOUT
2V/div
VUG
5V/div
VUG
5V/div
VLG
5V/div
VLG
10V/div
VFB
1V/div
IL
10A/div
Time 200µs/div
Time 20µs/div
MODE Transition DEM to CCM
MODE Transition CCM to DEM
VOUT
2V/div
VOUT
2V/div
VPHASE
10V/div
VPHASE
10V/div
VEN
2V/div
VEN
2V/div
Time 4ms/div
Time 4ms/div
Load Transient Response @ CCM
VOUT
100mV/div
Load Transient Response @ DEM
VOUT
100mV/div
IL
10A/div
IL
10A/div
Time 1ms/div
Time 1ms/div
AP3591
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AP3591
Application Information
1. Functional Description
The AP3591 is a synchronous step-down controller. Adaptive constant on time (COT) control is employed to provide fast transition response and
easy loop stabilization. AP3591 does not have a dedicated in board oscillator. It runs with a pseudo-constant frequency which is set by RON. The
output voltage variation is sensed by FB Pin. If VFB is below 0.75V, the error comparator will trigger the control logic and generate an ON-time
NEW PRODUCT
period, in which high side MOSFET is turned on and low side MOSFET is turned off. The ON-time period length is calculated using the following
equation:
t ON 
VOUT
VIN  f
VOUT is the output voltage, VIN is the input voltage, and f is the switching frequency.
The on-time is the time required for the voltage on this capacitor charging from zero volts to VOUT, thereby the ON-time of the high side switch is
directly proportional to the output voltage and inversely proportional to the input voltage. The implementation results in a nearly constant switching
frequency without the need of a clock generator.
tON = 14.5p×RTON×(VOUT+0.1)/VIN+50ns
After an ON-time period, the AP3591 goes into the OFF-time period. The OFF-time period length depends on VFB in most case. It will end when
VFB decreases below 0.75V and then the ON-time period is triggered again. If the OFF-time period is less than the minimum OFF time, the
minimum OFF time will be applied, which is about 400ns typical.
2. Mode Selection Operation
AP3591 has two operation modes: Continuous Conduction Mode (CCM) and Diode Emulation Mode (DEM). When the EN/DEM pin voltage is
higher than 2.9V, AP3591 will operate in DEM mode for high efficiency; when the EN/DEM pin is floating, AP3591 will operate in forced CCM
mode to a certain frequency during a light load condition.
2.1 Diode Emulation Mode
If the DEM mode is selected, the AP3591 automatically reduces the switching frequency under a light load condition to get high efficiency. When
the output current decreases and heavy load condition is formed, the inductor current decreases as well, and eventually comes close to zero
current, which is the boundary between CCM and DEM. The low side MOSFET will turn off whenever the inductor current reaches zero level. The
load is provided only by the output capacitor. When FB voltage is lower than 0.75V, the next ON cycle is beginning. The ON-time is kept the same
as that in the heavy load condition. The switching frequency increases to keep V OUT voltage when the output current increases from light to heavy
load. The transition load point is calculated using the following equation:
I LOAD 
VIN  VOUT
 tON
2L
tON is the on-time.
2.2 Continuous Conduction Mode
When AP3591 operates in CCM mode, the duty cycle V OUT/VIN is not changed at light load condition. The low side MOSFET keeps on even when
inductor current decreases to reverse. The benefit of CCM is to keep the switching frequency fairly constant to avoid a certain frequency during a
light load condition.
3. Power On Reset and Soft-start
Power on reset occurs when VDD rises above approximately 3.9V: the IC will reset the fault latch and prepare the PWM for operation. When V DD is
below 3.6V, the VDD under voltage lockout (UVLO) circuitry inhibits switching by keeping UGATE and LGATE low. A built-in soft-start is used to
prevent surge current from power supply input VIN during turn on (referring to Functional Block Diagram). The error amplifier is a three-input device.
Reference voltage VREF or the internal soft-start voltage VSS whichever is smaller dominates the behavior of the non-inverting inputs of the error
amplifier. VSS internally ramps up to 95% of 0.75V in 1.2ms for AP3591 after the soft-start cycle is initiated.
Figure 1 shows a typical start-up interval for AP3591 when the EN/DEM pin has been released from a grounded (system shutdown) state.
AP3591
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AP3591
Application Information (Cont.)
Power On from EN (DEM Mode)
NEW PRODUCT
VOUT
1V/div
VUGATE
20V/div
VEN
2V/div
VPGOOD
5V/div
Time 400µs/div
Figure 1. Start-up Behavior of AP3591
4. Power Good Output
The AP3591 features power good output to monitor the output voltage. It is an open-drain output and should be connected to a 5V power supply
node through a resistor. The power good function is active after the soft start is finished. PGOOD signal becomes high if output voltage reaches
±5% of the target value after 64µs delay building into the PGOOD circuitry. It will become low immediately if the output voltage goes beyond ±10%
of the target value.
5. Soft Stop
The AP3591 has a built in soft-stop circuitry. The output is discharged with an internal 20Ω transistor when EN/DEM is low or the device is in a
fault condition including UVLO and OTP. The discharge time constant is determined by the output capacitance and resistance of the discharge
transistor.
6. Pre-biased Output
Figure 2 shows the normal VOUT start-up curve in blue; Initialization begins at T0, and output ramps between T1 and T2. If the output is pre-biased
to a voltage less than the expected value, as shown by the magenta curve, the AP3591 will detect that condition. Neither MOSFET will turn on
until the soft-start ramp voltage exceeds the output. VOUT starts seamlessly ramping from there. If the output is pre-biased to a voltage above the
expected value, as showed in the black curve, neither MOSFET will turn on until the output voltage is pulled down to the expected value through
external load. Any resistive load connected to the output will help pull down the voltage.
VOUT Over-Charged
VOUT Pre-Biased
GND
VOUT Normal
T0
T1
T2
Figure 2. Start-up Behavior with Pre-biased Output Voltage
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
Application Information (Cont.)
7. Over Current Protection (OCP)
NEW PRODUCT
Figure 3 shows the over current protection (OCP) scheme of AP3591. In each switching cycle, the inductor current is sensed by monitoring the
low-side MOSFET in the OFF period. When the voltage between PGND pin and PHASE pin is larger than the over current trip level, the OCP is
triggered and the controller keeps the OFF state. Because the R DS(ON) of MOSFET increases with the temperature, I OC has 4500ppm/ºC
temperature coefficient to compensate this temperature dependency of RDS(ON).
REVERSE BUFFER
Ioc
OC
COMPARATOR
Q1
OPS
Q2
ROC- SET
CURRENT SENSE
Figure 3. Over Current Scheme
A resistor ROC-SET should be connected from CS pin to GND. An internal current source I OC (10µA typically), flowing through ROC-SET determines
the OCP trip point IOCSET, which can be calculated using the following equation:
VCS (mV )  10 mA  R OC-SET ( K)
The load current at over-current threshold (IO_OCSET), can be calculated using the following equation:
I O_OCSET 

VCS
R DS(ON)
VCS
R DS(ON)


I L ( PP)
2
(V  VOUT )  VOUT
1
 IN
2 L f
VIN
VOUT is the output voltage, ΔIL(PP) is the inductor current ripple peak to peak value and f is the switching frequency.
8. Negative Over Current Protection (NOCP)
The AP3591 supports cycle by cycle negative over current limiting in CCM mode. The over current limit value is the same absolute value as the
positive over current limit. If the inductor reverse current is larger than NOCP current at OFF time, the LMOSFET is turned off. The reverse current
will flows to VIN through the body diode of HMOSFET. After 400ns delay, LMOSFET is turned on again. If the NOCP is released, the HMOSFET
is turned on and the device resumes normal operation.
9. Under Voltage Protection (UVP)
The output voltage is also monitored for under voltage protection. When the output voltage is less than 70% of the setting voltage threshold, under
voltage protection is triggered after 28µs delay to prevent false transition. When UVP is triggered, UGATE and LGATE will get low, and the output
is discharged with the internal 20Ω transistor. UVP is a latched protection; it can only be released by VDD or EN/DEM power-on reset. The UVP
blanking time is 2ms during soft-start.
10. Under Voltage Lockout
The AP3591 provides an under voltage lockout circuit to prevent from undefined status at startup. The UVLO circuit shuts down the device when
VDD drops below 3.6V. The UVLO circuit has 300mV hysteresis, which means the device will start up again when V DD rises to 3.9V.
11. Over Voltage Protection (OVP)
The feedback voltage is continuously monitored for over voltage protection. When OVP is triggered, LGATE will go high and UGATE will go low to
discharge the output capacitor.
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
Application Information (Cont.)
The AP3591 provides full-time over voltage protection whenever soft-start completes or not. The typical OVP threshold is 125% of the internal
reference voltage VREF. The AP3591 provides latched OVP and can only be released by VDD or EN/DEM power-on reset. There is 33µs delay
NEW PRODUCT
built into the over voltage protection circuit to prevent false transitions.
VOUT
1V/div
VUGATE
20V/div
VLGATE
5V/div
Time 100µs/div
Figure 4. Over Voltage Protection
12. Thermal Shutdown
If the junction temperature of the device reaches the thermal shutdown limit of +160ºC, the AP3591 shuts itself off. Both UGATE and LGATE are
driven low, turning off both MOSFETs. The output is discharged with the internal 20Ω transistor. When the junction temperature cools down to the
required level (+140°C nominal), the device initiates soft-start as during a normal power-up cycle.
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
Ordering Information
AP3591 XX XX – XX
Package
Packing
RoHS/Green
FN : U-QFN3535-14
TR : Tape & Reel
G1 : Green
NEW PRODUCT
Product Name
Diodes IC’s Pb-free products with "G1" suffix in the part number, are RoHS compliant and green.
Package
Temperature
Range
U-QFN3535-14
-40 to +85C
Part Number
AP3591FNTR-G1
Marking ID
BHA
Packing
5000/Tape & Reel
Marking Information
(1)
U-QFN3535-14
(Top View)
First Line: Logo and Marking ID
Second and Third Lines: Date Code
Y: Year
WW: Work Week of Molding
A: Assembly House Code
th
th
XX: 7 and 8 Digits of Batch No.
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
Package Outline Dimensions (All dimensions in mm(inch).)
(1)
Package Type: U-QFN3535-14
NEW PRODUCT
Pin 1 Mark
1.900(0.075)
2.100(0.083)
0.200(0.008)
0.300(0.012)
N14
N1
PIN #1 IDENTIFICATION
See DETAIL A
N13
N2
3.400(0.134)
3.600(0.142)
0.500(0.020)
BSC
1.900(0.075)
2.100(0.083)
N6
N8
3.400(0.134)
3.600(0.142)
0.350(0.014)
0.450(0.018)
1.500(0.059)
BSC
A1
DETAIL A
1
1
1
2
2
2
3
3
3
4
4
4
0.000(0.000)
0.050(0.002)
Pin 1 options
0.750(0.030)
0.900(0.035)
A1
Symbol
min(mm) max(mm) min(inch) max(inch)
AP3591
Document number: DS36906 Rev. 1 - 2
Option1
0.203(REF)
0.008(REF)
Option2
0.150(REF)
0.006(REF)
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AP3591
Suggested Pad Layout
(1)
Package Type: U-QFN3535-14
E2
NEW PRODUCT
Y2
X1
E1
Y1
Y
Y3
X2
X3
X
Dimensions
X=Y
(mm)/(inch)
X1=Y1
(mm)/(inch)
X2=Y2
(mm)/(inch)
X3=Y3
(mm)/(inch)
E1
(mm)/(inch)
E2
(mm)/(inch)
Value
3.800/0.150
2.100/0.083
0.650/0.026
0.300/0.012
0.500/0.020
1.500/0.059
AP3591
Document number: DS36906 Rev. 1 - 2
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AP3591
IMPORTANT NOTICE
NEW PRODUCT
DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
(AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION).
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes
without further notice to this document and any product described herein. Diodes Incorporated does not assume any liability arising out of the
application or use of this document or any product described herein; neither does Diodes Incorporated convey any license under its patent or
trademark rights, nor the rights of others. Any Customer or user of this document or products described herein in such applications shall assume
all risks of such use and will agree to hold Diodes Incorporated and all the companies whose products are represented on Diodes Incorporated
website, harmless against all damages.
Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized sales channel.
Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall indemnify and
hold Diodes Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees arising out of, directly or
indirectly, any claim of personal injury or death associated with such unintended or unauthorized application.
Products described herein may be covered by one or more United States, international or foreign patents pending. Product names and markings
noted herein may also be covered by one or more United States, international or foreign trademarks.
This document is written in English but may be translated into multiple languages for reference. Only the English version of this document is the
final and determinative format released by Diodes Incorporated.
LIFE SUPPORT
Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without the express
written approval of the Chief Executive Officer of Diodes Incorporated. As used herein:
A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body, or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the
labeling can be reasonably expected to result in significant injury to the user.
B. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the
failure of the life support device or to affect its safety or effectiveness.
Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or systems, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any
use of Diodes Incorporated products in such safety-critical, life support devices or systems, notwithstanding any devices- or systems-related
information or support that may be provided by Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporated and its
representatives against any damages arising out of the use of Diodes Incorporated products in such safety-critical, life support devices or systems.
Copyright © 2014, Diodes Incorporated
www.diodes.com
AP3591
Document number: DS36906 Rev. 1 - 2
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