NCV8871
Automotive Grade
Non-Synchronous Boost
Controller
The NCV8871 is an adjustable output non−synchronous boost
controller which drives an external N−channel MOSFET. The device
uses peak current mode control with internal slope compensation. The
IC incorporates an internal regulator that supplies charge to the gate
driver.
Protection features include internally−set soft−start, undervoltage
lockout, cycle−by−cycle current limiting, hiccup−mode short−circuit
protection and thermal shutdown.
Additional features include low quiescent current sleep mode and
externally−synchronizable switching frequency.
Features
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MARKING
DIAGRAM
8
8
1
SOIC−8
D SUFFIX
CASE 751
1
8871xx = Specific Device Code
xx = 00, 01, 02, 03, 04
A
= Assembly Location
L
= Wafer Lot
Y
= Year
W
= Work Week
G
= Pb−Free Package
8871xx
ALYW
G
•
•
•
•
•
•
•
•
•
•
•
•
Peak Current Mode Control with Internal Slope Compensation
1.2 V
±2%
Reference voltage
Fixed Frequency Operation
Wide Input Voltage Range of 3.2 V to 40 Vdc, 45 V Load Dump
Input Undervoltage Lockout (UVLO)
Internal Soft−Start
Low Quiescent Current in Sleep Mode
Cycle−by−Cycle Current Limit Protection
Hiccup−Mode Overcurrent Protection (OCP)
Hiccup−Mode Short−Circuit Protection (SCP)
Thermal Shutdown (TSD)
This is a Pb−Free Device
PIN CONNECTIONS
EN/SYNC 1
ISNS 2
GND 3
GDRV 4
(Top View)
8 VFB
7 VC
6 VIN
5 VDRV
ORDERING INFORMATION
Device
NCV887100D1R2G
NCV887101D1R2G
NCV887102D1R2G
NCV887103D1R2G
NCV887104D1R2G
Package
SOIC−8
(Pb−Free)
SOIC−8
(Pb−Free)
SOIC−8
(Pb−Free)
SOIC−8
(Pb−Free)
SOIC−8
(Pb−Free)
Shipping
†
2500 / Tape &
Reel
2500 / Tape &
Reel
2500 / Tape &
Reel
2500 / Tape &
Reel
2500 / Tape &
Reel
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specification
Brochure, BRD8011/D.
©
Semiconductor Components Industries, LLC, 2017
October, 2018
−
Rev. 14
1
Publication Order Number:
NCV8871/D
NCV8871
VIN
C
DRV
VDRV
GDRV
ISNS
GND
R
SNS
R
F1
Gm
SS
V
ref
8
VFB
R
F2
C
o
L
D
V
o
Q
C
g
V
g
TEMP
FAULT
LOGIC
EN/
SYNC
EN/SYNC
1
OSC
PWM
SC
VC
R
C
C
C
CLK
DRIVE
LOGIC
CSA
VDRV
6
5
4
2
3
SCP
CL
+
7
Figure 1. Simplified Block Diagram and Application Schematic
PACKAGE PIN DESCRIPTIONS
Pin No.
1
2
3
4
Pin
Symbol
EN/SYNC
ISNS
GND
GDRV
Function
Enable and synchronization input. The falling edge synchronizes the internal oscillator. The part is disabled
into sleep mode when this pin is brought low for longer than the enable time−out period.
Current sense input. Connect this pin to the source of the external N−MOSFET, through a current−sense
resistor to ground to sense the switching current for regulation and current limiting.
Ground reference.
Gate driver output. Connect to gate of the external N−MOSFET. A series resistance can be added from
GDRV to the gate to tailor EMC performance. An R
GND
= 15 kW (typical) GDRV−GND resistor is strongly
recommended.
Driving voltage. Internally−regulated supply for driving the external N−MOSFET, sourced from VIN. Bypass
with a 1.0
mF
ceramic capacitor to ground.
Input voltage. If bootstrapping operation is desired, connect a diode from the input supply to VIN, in addi-
tion to a diode from the output voltage to VDRV and/or VIN.
Output of the voltage error amplifier. An external compensator network from VC to GND is used to stabilize
the converter.
Output voltage feedback. A resistor from the output voltage to VFB with another resistor from VFB to GND
creates a voltage divider for regulation and programming of the output voltage.
5
6
7
8
VDRV
VIN
VC
VFB
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2
NCV8871
ABSOLUTE MAXIMUM RATINGS
(Voltages are with respect to GND, unless otherwise indicated)
Rating
Dc Supply Voltage (VIN)
Peak Transient Voltage (Load Dump on VIN)
Dc Supply Voltage (VDRV, GDRV)
Peak Transient Voltage (VFB)
Dc Voltage (VC, VFB, ISNS)
Dc Voltage (EN/SYNC)
Dc Voltage Stress (VIN
−
VDRV)*
Operating Junction Temperature
Storage Temperature Range
Peak Reflow Soldering Temperature: Pb−Free, 60 to 150 seconds at 217°C
Value
−0.3
to 40
45
12
−0.3
to 6
−0.3
to 3.6
−0.3
to 6
−0.7
to 45
−40
to 150
−65
to 150
265 peak
Unit
V
V
V
V
V
V
V
°C
°C
°C
Stresses exceeding those listed in the Maximum Ratings table may damage the device. If any of these limits are exceeded, device functionality
should not be assumed, damage may occur and reliability may be affected.
*An external diode from the input to the VIN pin is required if bootstrapping VDRV and VIN off of the output voltage.
PACKAGE CAPABILITIES
Characteristic
ESD Capability (All Pins)
Moisture Sensitivity Level
Package Thermal Resistance
1. 1 in
2
, 1 oz copper area used for heatsinking.
Junction−to−Ambient, R
qJA
(Note 1)
Human Body Model
Machine Model
Value
w2.0
w200
1
100
Unit
kV
V
−
°C/W
Device Variations
The NCV8871 features several variants to better fit a
multitude of applications. The table below shows the typical
TYPICAL VALUES
Part No.
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
D
max
88%
86%
91%
93%
93%
f
s
170 kHz
1000 kHz
1000 kHz
340 kHz
340 kHz
t
ss
7.4 ms
1.25 ms
1.25 ms
3.7 ms
3.7 ms
S
a
53 mV/ms
16 mV/ms
53 mV/ms
53 mV/ms
53 mV/ms
values of parameters for the parts that are currently
available.
V
cl
400 mV
400 mV
400 mV
200 mV
200 mV
I
src
800 mA
575 mA
800 mA
575 mA
800 mA
I
sink
600 mA
350 mA
600 mA
350 mA
600 mA
V
DRV
10.5 V
6.3 V
6.3 V
8.4 V
8.4 V
SCE
Y
Y
N
Y
N
DEFINITIONS
Symbol
D
max
S
a
I
sink
Characteristic
Maximum Duty Cycle
Slope Compensating Ramp
Gate Drive Sinking Current
Symbol
f
s
V
cl
V
DRV
Characteristic
Switching Frequency
Current Limit Trip Voltage
Drive Voltage
Symbol
t
ss
I
src
SCE
Characteristic
Soft−Start Time
Gate Drive Sourcing Current
Short Circuit Enable
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NCV8871
ELECTRICAL CHARACTERISTICS
(−40°C < T
J
< 150°C, 3.2 V < V
IN
< 40 V, unless otherwise specified) Min/Max values are
guaranteed by test, design or statistical correlation.
Characteristic
GENERAL
Quiescent Current, Sleep Mode
Quiescent Current, Sleep Mode
Quiescent Current, No switching
Quiescent Current, Switching,
normal operation
OSCILLATOR
Minimum pulse width
Maximum duty cycle
t
on,min
D
max
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
From start of switching with V
FB
= 0 until
reference voltage = V
REF
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
From EN
→
1 until start of switching with
V
FB
= 0
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
90
86
84
89
91
91
153
900
900
306
306
115
88
86
91
93
93
170
1000
1000
340
340
140
90
88
93
95
95
187
1100
1100
374
374
ns
%
I
q,sleep
I
q,sleep
I
q,off
I
q,on
V
IN
= 13.2 V, EN = 0, T
J
= 25°C
V
IN
= 13.2 V, EN = 0,
−40°C
< T
J
< 125°C
Into VIN pin, EN = 1, No switching
Into VIN pin, EN = 1, Switching
−
−
−
−
2.0
2.0
1.5
3.0
−
6.0
2.5
6.0
mA
mA
mA
mA
Symbol
Conditions
Min
Typ
Max
Unit
Switching frequency
f
s
kHz
Soft−start time
t
ss
ms
6.0
1.0
1.0
3.0
3.0
−
46
13
46
46
46
7.4
1.25
1.25
3.7
3.7
240
53
16
53
53
53
8.8
1.5
1.5
4.4
4.4
280
60
19
60
60
60
ms
mV/ms
Soft−start delay
Slope compensating ramp
t
ss,dly
S
a
ENABLE/SYNCHRONIZATION
EN/SYNC pull−down current
EN/SYNC input high voltage
EN/SYNC input low voltage
EN/SYNC time−out ratio
I
EN/SYNC
V
s,ih
V
s,il
%t
en
From SYNC falling edge, to oscillator con-
trol (EN high) or shutdown (EN low), Per-
cent of typical switching period
Percent of f
s
From SYNC falling edge to GDRV falling
edge under open loop conditions
V
EN/SYNC
= 5 V
V
IN
> V
UVLO
−
2.0
0
−
5.0
−
−
−
10
5.0
800
350
mA
V
mV
%
SYNC minimum frequency ratio
SYNC maximum frequency
Synchronization delay
Synchronization duty cycle
CURRENT SENSE AMPLIFIER
Low−frequency gain
Bandwidth
ISNS input bias current
%f
sync,min
f
sync,max
t
s,dly
D
sync
A
csa
BW
csa
I
sns,bias
−
1.1
−
25
−
−
50
−
80
−
100
75
%
MHz
ns
%
Input−to−output gain at dc, ISNS
v
1 V
Gain of A
csa
−
3 dB
Out of ISNS pin
0.9
2.5
−
1.0
−
30
1.1
−
50
V/V
MHz
mA
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NCV8871
ELECTRICAL CHARACTERISTICS
(−40°C < T
J
< 150°C, 3.2 V < V
IN
< 40 V, unless otherwise specified) Min/Max values are
guaranteed by test, design or statistical correlation.
Characteristic
CURRENT SENSE AMPLIFIER
Current limit threshold voltage
V
cl
Voltage on ISNS pin
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
CL tripped until GDRV falling edge,
V
ISNS
= V
cl
(typ) + 60 mV
Percent of V
cl
From overcurrent event, Until switching
stops, V
ISNS
= V
OCP
+ 40 mV
360
360
360
180
180
−
125
−
400
400
400
200
200
80
150
−
440
440
440
220
220
125
175
125
mV
Symbol
Conditions
Min
Typ
Max
Unit
Current limit,
Response time
Overcurrent protection,
Threshold voltage
Overcurrent protection,
Response Time
t
cl
%V
ocp
t
ocp
ns
%
ns
VOLTAGE ERROR OPERATIONAL TRANSCONDUCTANCE AMPLIFIER
Transconductance
VEA output resistance
VFB input bias current
Reference voltage
VEA maximum output voltage
VEA minimum output voltage
VEA sourcing current
VEA sinking current
GATE DRIVER
Sourcing current
I
src
V
DRV
≥
6 V, V
DRV
−
V
GDRV
= 2 V
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
V
GDRV
≥
2 V
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
V
IN
−
V
DRV
, Iv
DRV
= 25 mA
V
IN
−
V
DRV
= 1 V
V
DRV
−
V
IN
, I
d,bd
= 5 mA
I
VDRV
= 0.1
−
25 mA
NCV887100
NCV887101
NCV887102
NCV887103
NCV887104
600
400
600
400
600
500
250
500
250
500
−
35
−
10
6.0
6.0
8.0
8.0
800
575
800
575
800
600
350
600
350
600
0.3
45
−
10.5
6.3
6.3
8.4
8.4
−
−
−
−
−
−
−
−
−
−
0.6
−
0.7
11
6.6
6.6
8.8
8.8
mA
g
m,vea
R
o,vea
I
vfb,bias
V
ref
V
c,max
V
c,min
I
src,vea
I
snk,vea
VEA output current, Vc = 2.0 V
VEA output current, Vc = 0.7 V
Current out of VFB pin
V
FB
– V
ref
=
±
20 mV
0.8
2.0
−
1.176
2.5
−
80
80
1.2
−
0.5
1.200
−
−
100
100
1.63
−
2.0
1.224
−
0.3
−
−
mS
MW
mA
V
V
V
mA
mA
Sinking current
I
sink
mA
Driving voltage dropout
Driving voltage source current
Backdrive diode voltage drop
Driving voltage
V
drv,do
I
drv
V
d,bd
V
DRV
V
mA
V
V
UVLO
Undervoltage lock−out,
Threshold voltage
Undervoltage lock−out,
Hysteresis
V
uvlo
V
uvlo,hys
V
IN
falling
V
IN
rising
3.0
50
3.1
125
3.2
200
V
mV
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