DATASHEET
ISL78840ASxH, ISL78841ASxH, ISL78843ASxH, ISL78845ASxH, ISL738840ASEH,
ISL738841ASEH, ISL738843ASEH, ISL738845ASEH
FN7952
Rev.4.00
Radiation Hardened, High Performance Industry Standard Single-Ended Current Mode PWM Controller
Feb 25, 2020
The
ISL78840ASEH, ISL78841ASEH, ISL78843ASEH,
ISL78845ASEH, ISL78840ASRH, ISL78841ASRH,
ISL78843ASRH, ISL78845ASRH, ISL738840ASEH,
ISL738841ASEH, ISL738843ASEH, ISL738845ASEH
are high
performance, radiation hardened drop-in replacements for the
popular 28C4x and 18C4x PWM controllers suitable for a wide
range of power conversion applications including boost,
flyback, and isolated output configurations. Fast signal
propagation and output switching characteristics make these
ideal products for existing and new designs.
Features include up to 13.2V operation, low operating current,
90µA typical start-up current, adjustable operating frequency
to 1MHz and high peak current drive capability with 50ns rise
and fall times.
Features
• Electrically screened to DLA SMD #5962-07249
• QML qualified per MIL-PRF-38535 requirements
• 1A MOSFET gate driver
• 90µA typical start-up current, 125µA maximum
• 35ns propagation delay current sense to output
• Fast transient response with peak current-mode control
• 9V to 13.2V operation
• Adjustable switching frequency to 1MHz
• 50ns rise and fall times with 1nF output load
• Trimmed timing capacitor discharge current for accurate
dead time/maximum duty cycle control
• 1.5MHz bandwidth error amplifier
• Tight tolerance voltage reference over line, load, and
temperature
• ±3% current limit threshold
• Pb-free available (RoHS compliant)
• Radiation acceptance testing - ISL7884xASEH
- HDR (50-300rad(Si)/s): 100krad(Si)
- LDR (0.01rad(Si)/s): 50krad(Si)
• Radiation acceptance testing - ISL7884xASRH
- HDR (50-300rad(Si)/s): 100krad(Si)
• Radiation acceptance testing - ISL73884xASEH
- LDR (0.01rad(Si)/s): 50krad(Si)
Applications
• Current mode switching power supplies
• Isolated buck and flyback regulators
• Boost regulators
• Direction and speed control in motors
• Control of high current FET drivers
Related Literature
For a full list of related documents, visit our website:
•
ISL78840ASEH, ISL78841ASEH, ISL78843ASEH,
ISL78845ASEH, ISL78840ASRH, ISL78841ASRH,
ISL78843ASRH, ISL78845ASRH, ISL738840ASEH,
ISL738841ASEH, ISL738843ASEH,
and
ISL738845ASEH
device pages
TABLE 1. KEY DIFFERENCES BETWEEN FAMILY OF PARTS
PART NUMBER
ISL78840ASxH
ISL78841ASxH
ISL78843ASxH
ISL78845ASxH
ISL738840ASEH
ISL738841ASEH
ISL738843ASEH
ISL738845ASEH
RISING UVLO
(V)
7.0
7.0
8.4
8.4
7.0
7.0
8.4
8.4
MAXIMUM DUTY CYCLE
(%)
100
50
100
50
100
50
100
50
FN7952 Rev.4.00
Feb 25, 2020
Page 1 of 18
ISL78840ASxH, ISL78841ASxH, ISL78843ASxH, ISL78845ASxH, ISL738840ASEH, ISL738841ASEH, ISL738843ASEH, ISL738845ASEH
Ordering Information
ORDERING NUMBER
(Note
1)
5962R0724905VPC
5962R0724906VPC
5962R0724907VPC
5962R0724908VPC
5962R0724905VXC
5962R0724906VXC
5962R0724907VXC
5962R0724908VXC
5962R0724905V9A
5962R0724906V9A
5962R0724907V9A
5962R0724908V9A
5962R0724901V9A
N/A
N/A
5962R0724901QXC
5962R0724901VXC
N/A
5962R0724901QPC
5962R0724901VPC
5962R0724902V9A
N/A
N/A
5962R0724902QXC
5962R0724902VXC
N/A
5962R0724902QPC
5962R0724902VPC
5962R0724903V9A
N/A
N/A
5962R0724903QXC
5962R0724903VXC
N/A
5962R0724903QPC
5962R0724903VPC
5962R0724904V9A
N/A
N/A
PART NUMBER
(Note
2)
ISL78840ASEHVD
ISL78841ASEHVD
ISL78843ASEHVD
ISL78845ASEHVD
ISL78840ASEHVF
ISL78841ASEHVF
ISL78843ASEHVF
ISL78845ASEHVF
ISL78840ASEHVX (Note
3)
ISL78841ASEHVX (Note
3)
ISL78843ASEHVX (Note
3)
ISL78845ASEHVX (Note
3)
ISL78840ASRHVX (Note
3)
HDR to 100krad(Si)
RADIATION HARDNESS
(Total Ionizing Dose)
HDR to 100krad(Si),
LDR to 50krad(Si)
TEMP. RANGE
(°C)
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
N/A
HDR to 100krad(Si)
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
N/A
HDR to 100krad(Si)
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
N/A
HDR to 100krad(Si)
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
PACKAGE
PKG.
(RoHS Compliant) DWG. #
8 Ld SBDIP
8 Ld SBDIP
8 Ld SBDIP
8 Ld SBDIP
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
Die
Die
Die
Die
Die
Die
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
8 Ld SBDIP
8 Ld SBDIP
8 Ld SBDIP
Die
Die
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
8 Ld SBDIP
8 Ld SBDIP
8 Ld SBDIP
Die
Die
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
8 Ld SBDIP
8 Ld SBDIP
8 Ld SBDIP
Die
Die
8 Ld Flatpack
K8.A
K8.A
K8.A
K8.A
D8.3
D8.3
D8.3
K8.A
K8.A
K8.A
D8.3
D8.3
D8.3
K8.A
K8.A
K8.A
D8.3
D8.3
D8.3
D8.3
D8.3
D8.3
D8.3
K8.A
K8.A
K8.A
K8.A
ISL78840ASRHX/SAMPLE (Notes
3, 4)
N/A
ISL78840ASRHF/PROTO (Note
4)
ISL78840ASRHQF
ISL78840ASRHVF
ISL78840ASRHD/PROTO (Note
4)
ISL78840ASRHQD
ISL78840ASRHVD
ISL78841ASRHVX (Note
3)
ISL78841ASRHX/SAMPLE (Notes
3, 4)
N/A
ISL78841ASRHF/PROTO (Note
4)
ISL78841ASRHQF
ISL78841ASRHVF
ISL78841ASRHD/PROTO (Note
4)
ISL78841ASRHQD
ISL78841ASRHVD
ISL78843ASRHVX (Note
3)
ISL78843ASRHX/SAMPLE (Notes
3, 4)
N/A
ISL78843ASRHF/PROTO (Note
4)
ISL78843ASRHQF
ISL78843ASRHVF
ISL78843ASRHD/PROTO (Note
4)
ISL78843ASRHQD
ISL78843ASRHVD
ISL78845ASRHVX (Note
3)
ISL78845ASRHX/SAMPLE (Notes
3, 4)
N/A
ISL78845ASRHF/PROTO (Note
4)
N/A
N/A
HDR to 100krad(Si)
N/A
HDR to 100krad(Si)
N/A
HDR to 100krad(Si)
FN7952 Rev.4.00
Feb 25, 2020
Page 2 of 18
ISL78840ASxH, ISL78841ASxH, ISL78843ASxH, ISL78845ASxH, ISL738840ASEH, ISL738841ASEH, ISL738843ASEH, ISL738845ASEH
Ordering Information
(Continued)
ORDERING NUMBER
(Note
1)
5962R0724904QXC
5962R0724904VXC
N/A
5962R0724904QPC
5962R0724904VPC
5962L0724909VXC
5962L0724909VPC
5962L0724909V9A
N/A
N/A
N/A
5962L0724910VXC
5962L0724910VPC
5962L0724910V9A
N/A
N/A
N/A
5962L0724911VXC
5962L0724911VPC
5962L0724911V9A
N/A
N/A
N/A
5962L0724912VXC
5962L0724912VPC
5962L0724912V9A
N/A
N/A
N/A
NOTES:
1. These Pb-free Hermetic packaged products employ 100% Au plate - e4 termination finish, which is RoHS compliant and compatible with both SnPb
and Pb-free soldering operations.
2. Specifications for Rad Hard QML devices are controlled by the Defense Logistics Agency Land and Maritime (DLA). The SMD numbers listed must be
used when ordering.
3. Die product tested at T
A
= + 25°C. The wafer probe test includes functional and parametric testing sufficient to make the die capable of meeting the
electrical performance outlined in
“Electrical Specifications” on page 9.
4. The /PROTO and /SAMPLE are not rated or certified for Total Ionizing Dose (TID) or Single Event Effect (SEE) immunity. These parts are intended for
engineering evaluation purposes only. The /PROTO parts meet the electrical limits and conditions across temperature specified in the DLA SMD and
are in the same form and fit as the qualified device. The /SAMPLE parts are capable of meeting the electrical limits and conditions specified in the
DLA SMD. The /SAMPLE parts do not receive 100% screening across temperature to the DLA SMD electrical limits. These part types do not come
with a Certificate of Conformance because they are not DLA qualified devices.
PART NUMBER
(Note
2)
ISL78845ASRHQF
ISL78845ASRHVF
ISL78845ASRHD/PROTO (Note
4)
ISL78845ASRHQD
ISL78845ASRHVD
ISL738840ASEHVF
ISL738840ASEHVD
ISL738840ASEHVX (Note
3)
ISL738840ASEHF/PROTO (Note
4)
ISL738840ASEHD/PROTO (Note
4)
ISL738840ASEHX/SMPL (Notes
3, 4)
ISL738841ASEHVF
ISL738841ASEHVD
ISL738841ASEHVX (Note
3)
ISL738841ASEHF/PROTO (Note
4)
ISL738841ASEHD/PROTO (Note
4)
ISL738841ASEHX/SMPL (Notes
3, 4)
ISL738843ASEHVF
ISL738843ASEHVD
ISL738843ASEHVX (Note
3)
ISL738843ASEHF/PROTO (Note
4)
ISL738843ASEHD/PROTO (Note
4)
ISL738843ASEHX/SMPL (Notes
3, 4)
ISL738845ASEHVF
ISL738845ASEHVD
ISL738845ASEHVX (Note
3)
ISL738845ASEHF/PROTO (Note
4)
ISL738845ASEHD/PROTO (Note
4)
ISL738845ASEHX/SMPL (Notes
3, 4)
N/A
N/A
N/A
N/A
N/A
N/A
LDR to 50krad(Si)
N/A
N/A
N/A
LDR to 50krad(Si)
N/A
N/A
N/A
LDR to 50krad(Si)
LDR to 50krad(Si)
N/A
HDR to 100krad(Si)
RADIATION HARDNESS
(Total Ionizing Dose)
HDR to 100krad(Si)
TEMP. RANGE
(°C)
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
-55 to +125
PACKAGE
PKG.
(RoHS Compliant) DWG. #
8 Ld Flatpack
8 Ld Flatpack
8 Ld SBDIP
8 Ld SBDIP
8 Ld SBDIP
8 Ld Flatpack
8 Ld Flatpack
Die
8 Ld Flatpack
8 Ld Flatpack
Die
8 Ld Flatpack
8 Ld Flatpack
Die
8 Ld Flatpack
8 Ld Flatpack
Die
8 Ld Flatpack
8 Ld Flatpack
Die
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
8 Ld Flatpack
Die
8 Ld Flatpack
8 Ld Flatpack
Die
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
K8.A
D8.3
D8.3
D8.3
K8.A
K8.A
FN7952 Rev.4.00
Feb 25, 2020
Page 3 of 18
ISL78840ASxH, ISL78841ASxH, ISL78843ASxH, ISL78845ASxH, ISL738840ASEH, ISL738841ASEH, ISL738843ASEH, ISL738845ASEH
Pin Configurations
ISL78840ASEH, ISL78841ASEH, ISL78843ASEH, ISL78845ASEH,
ISL78840ASRH, ISL78841ASRH, ISL78843ASRH, ISL78845ASRH,
ISL738840ASEH, ISL738841ASEH, ISL738843ASEH, ISL738845ASEH
(8 LD FLATPACK)
TOP VIEW
COMP
FB
CS
RTCT
1
2
3
4
8
7
6
5
V
REF
V
DD
OUT
GND
ISL78840ASEH, ISL78841ASEH, ISL78843ASEH,
ISL78845ASEH, ISL78840ASRH, ISL78841ASRH,
ISL78843ASRH, ISL78845ASRH
(8 LD SBDIP)
TOP VIEW
COMP
FB
CS
RTCT
1
2
3
4
8
7
6
5
V
REF
V
DD
OUT
GND
Pin Descriptions
PIN NAME
RTCT
PIN NUMBER
4
ESD CIRCUIT
1
DESCRIPTION
The oscillator timing control pin. The operational frequency and maximum duty cycle are set by
connecting a resistor, RT, between V
REF
and this pin and a timing capacitor, CT, from this pin to GND.
The oscillator produces a sawtooth waveform with a programmable frequency range up to 2.0MHz. The
charge time, t
C
, the discharge time, t
D
, the RTCT oscillator frequency, f, and the maximum duty cycle,
D
MAX
, can be approximated from
Equations 1
through
4:
t
C
0.533
RT
CT
0.008
RT
–
3.83
-
t
D
–
RT
CT
In
--------------------------------------------
0.008
RT
–
1.71
f
=
1
t
C
+
t
D
(EQ. 1)
(EQ. 2)
(EQ. 3)
(EQ. 4)
D
=
t
C
f
The formulas have increased error at higher frequencies due to propagation delays.
Figure 7
may be
used as a guideline in selecting the capacitor and resistor values required for a given oscillator
frequency for the ISL7884xASxH and ISL73884xASEH . The switching frequency for the
ISL78841ASxH/ISL738841ASEH and ISL78845ASxH/ISL738845ASEH will be half the RTCT oscillator
frequency.
COMP
1
2
3
5
6
1
1
1
-
3
COMP is the output of the error amplifier and the input of the PWM comparator. The control loop
frequency compensation network is connected between the COMP and FB pins.
The output voltage feedback is connected to the inverting input of the error amplifier through this pin.
The noninverting input of the error amplifier is internally tied to a reference voltage.
The current sense input to the PWM comparator. The range of the input signal is nominally 0V to 1.0V
and has an internal offset of 100mV.
GND is the power and small signal reference ground for all functions.
The drive output to the power switching device. It is a high current output capable of driving the gate of
a power MOSFET with peak currents of 1.0A. This GATE output is actively held low when VDD is below
the UVLO threshold.
V
DD
is the power connection for the device. The total supply current will depend on the load applied to
OUT. Total I
DD
current is the sum of the operating current and the average output current. Knowing the
operating frequency, f and the MOSFET gate charge, Qg, the average output current can be calculated
from
Equation 5:
I
OUT
=
Qg
f
(EQ. 5)
FB
CS
GND
OUT
V
DD
7
2
To optimize noise immunity, bypass V
DD
to GND with a ceramic capacitor as close to the V
DD
and GND
pins as possible.
FN7952 Rev.4.00
Feb 25, 2020
Page 4 of 18
ISL78840ASxH, ISL78841ASxH, ISL78843ASxH, ISL78845ASxH, ISL738840ASEH, ISL738841ASEH, ISL738843ASEH, ISL738845ASEH
Pin Descriptions
(Continued)
PIN NAME
V
REF
PIN NUMBER
8
ESD CIRCUIT
1
DESCRIPTION
The 5.00V reference voltage output. +1.0/-1.5% tolerance over line, load and operating temperature.
The recommended bypass to GND cap is in the range 0.1µF to 0.22µF. A typical value of 0.15µF can be
used.
PACKAGE PIN
VDD
12V (BODY DIODE)
12V
36V
OUT
12V (BODY DIODE)
GND
CIRCUIT 1
GND
CIRCUIT 2
GND
CIRCUIT 3
PACKAGE PIN
FN7952 Rev.4.00
Feb 25, 2020
Page 5 of 18
电子竞赛
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
