Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
1
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise
customers to obtain the latest version of relevant information to verify before placing orders.
8-PIN Synchronous Buck PWM Controller
•••••
Operating with Single 5V or 12V Input
•••••
Drives N-Channel MOSFETs
•••••
Simple Single-Loop Control Design
−
Voltage-Mode PWM Control
−
Full 0% to 100% Duty Ratio
−
Fast Transient Response
•••••
±2% Output Voltage Accuracy Over Temperature
•••••
Under-Voltage Protection for Output
•••••
200kHz Constant Frequency Operation
(400kHz for APW7037A)
•••••
Small size, 8-PIN Package (SOIC or TSSOP)
Features
Applications
•••••
Graphics Cards
•••••
DDR Memory Power Supply
•••••
DDR Memory Termination Voltage
•••••
Low-Voltage Distributed Power Supplies
General Description
The APW7037/A controller IC is designed to provide
a low cost synchronous Buck regulator for on-board
DC to DC converter applications. The APW7037 to-
gether with dual N-channel MOSFETs such as
APM7313, provide a low cost solution for such
applications. This device features an internal 200KHz
oscillator (400KHz for “A” version), Power-On-Reset
(POR) for both VCC and VC supplies, an external
programmable soft-start function as well as output
under-voltage detection that latches off the device
when an output short is detected.
Pin Description
Ordering and Marking Information
APW 7037/A
Handling Code
Tem p. R ange
P ackage Code
P ackage Code
K : S O -8 R : T S S O P -8
O perating Junction Tem p. R ange
C : 0 to 70°C
Handling Code
TU : Tube
TR : Tape & Reel
A P W 7037/A K :
A P W 7037/A
X X X X X
X X X X X - D ate Code
A P W 7037/A R :
A P W 7037/A
X X X X X
X X X X X - D ate Code
1
2
3
4
5
6
7
8
FB
VCC
LDRV
GND
HDRV
VC
COMP
SS
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
2
Absolute Maximum Ratings
Block Diagram
Thermal Characteristics
Symbol
Parameter
Value
Unit
θ
JA
Thermal Resistance in Free Air
8-pin SOIC
8-pin TSSOP
160
124
°C/W
V CC
VCC
VC
HDRV
LDRV
OSC
Gate
Control
V
R EF
SS
20uA
3.3V
GND
F
OSC
COM P
Error
A mp.
FB
PWM
25k
25k
V
FBU V
Under-V oltage
Regulator
4.5V
Max .
64uA
POR
Pow er
On Reset
Description
Rating
Unit
VCC to GND
-0.2~30
V
VC to GND
-0.2~30
V
Operating Junction Temperature
0~125
°C
Storage Temperature
-65~150
°C
Soldering Temperature (10 Seconds)
300
°C
Minimum ESD Rating
±2
kV
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
3
Electrical Characteristics
Unless otherwise specified, these specifications apply over VCC=5V, VC=12V and T
A
=0 to 70°C. Typical values refer
to T
A
=25°C.
APW7037/A
Unit
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
SUPPLY CURRENT
I
CC
VCC Dynamic Supply Current F
OSC
=200KHz, C
L
=1500pF
2
3
5
mA
I
C
VC Dynamic Supply Current F
OSC
=200KHz, C
L
=1500pF
2
5.5
8
mA
I
CCQ
VCC Static Supply Current
SS=GND
0.5
1.5
3
mA
I
CQ
VC Static Supply Current
SS=GND
0.2
0.4
1
mA
POWER-ON RESET
Rising VCC Threshold
4.0
4.2
4.4
V
VCC POR Hysteresis
0.25
V
Rising VC Threshold
3.1
3.3
3.5
V
VC POR Hysteresis
0.2
V
OSCILLATOR
F
OSC
Free Running Frequency
APW7037
APW7037A
180
360
200
400
220
440
KHz
∆V
OSC
Ramp Amplitude
1.10
V
ERROR AMPLIFIER
I
FB1
FB Pin Input Bias Current
SS=3V, V
FB
=1V
1
nA
I
FB2
FB Pin Input Bias Current
SS=0V, V
FB
=1V
-64
µA
GM
Transconductance
450
600
750
µmho
REFERENCE VOLTAGE
V
FB
FB Pin Regulation Voltage
APW7037
APW7037A
1.225
0.784
1.250
0.800
1.275
0.816
V
LREG V
FB
Line Regulation
VCC = 5~12V
0.2
0.35
%
GATE DRIVERS
HDRV Rising Time
C
L
= 1500pF
20
50
nS
HDRV Falling Time
C
L
= 1500pF
15
50
nS
LDRV Rising Time
C
L
= 1500pF
25
50
nS
LDRV Falling Time
C
L
= 1500pF
25
50
nS
Dead Band Time
50
150
250
nS
PROTECTION
V
FBUV
FB Under-Voltage Threshold V
FB
Falling APW7037
APW7037A
0.4
0.3
0.6
0.4
0.8
0.5
V
V
SD
Shutdown Threshold Voltage Pull the voltage of SS pin
0.5
V
I
SS
Soft-Start Current
SS=0
10
20
30
µA
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
4
1+
R
OUT
R
GND
(
)
Functional Pin Description
FB (Pin 1)
Connect this pin to the output (V
OUT
) of the PWM con-
verter via an external resistor divider to provide a volt-
age feedback path for the converter. The output volt-
age set by the resistor divider is determined using the
following formula :
V
OUT
= V
REF
x
where R
OUT
is the resistor connected from V
OUT
to FB
, and R
GND
is the resistor connected from FB to ground.
The voltage at this pin is also monitored for Under-
Voltage protection.
VCC (Pin 2)
Connect this pin to input voltage from 5V to 20V. This
pin provides the bias for the control circuitry and the
low-side power MOSFET driver (LDRV). The voltage
at this pin is monitored for Power-On Reset (POR)
purpose.
LDRV (Pin 3)
Connect this pin to the gate of the low-side power
MOSFET. This pin provides the gate drive for the
MOSFET.
GND (Pin 4)
Signal and power ground for the IC. All voltage levels
are measured with respect to this pin.
HDRV (Pin 5)
Connect this pin to the gate of the high-side power
MOSFET. This pin provides the gate drive for the
MOSFET.
VC (Pin 6)
This pin provides bias voltage to the high-side
MOSFET driver. A bootstrap circuit may be used to
pump a boot voltage for enforcing the driving capabil-
ity of the gate driver and improving the performance of
the MOSFET.
COMP (Pin 7)
This pin is the output of the error amplifier. Add an
external resistor-capacitor network to provide a loop
compensation for the PWM converter.
SS (Pin 8)
Connect a capacitor from this pin to ground.This
capacitor, along with an internal 20uA current source,
sets the soft-start interval of the PWM converter and
prevents the outputs from overshoot as well as limits
the input current. Pull this pin below 0.5V can shut-
down the converter.
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
5
Typical Applications
1. Dual supply voltage(5V and 12V) application
2. Single supply voltage(5V) application
V
IN
+ 5V
V
OU T
1.5V /5 A
C7
0.1uF
C5
1uF
C4
100uF
C3
47uF
C6,C9
2 x 150uF
R1
249
R2
1.24k
Q 1A
A P M 7313
L3
1uH
HDRV
5
LDRV
3
V C
6
FB
1
V CC
2
G ND
4
S S
8
CO M P
7
C8
2200pF
R3
24k
Q 1B
A P M 7313
C1
1uF
L4
3.3uH
U1
A P W 7037
C2
1uF
+ 12V
Q 2
A P M 2300A
Shutdown
R4
3
V
IN
+5V
V
OU T
1.5V/5 A
C8
0.1uF
C3
0.1uF
C6
1uF
C5
100uF
C4
47uF
C7,C10
2 x150uF
R1
249
R2
1.24k
Q1A
APM7312
L3
1uH
HDRV
5
LDRV
3
V C
6
FB
1
V CC
2
G ND
4
S S
8
CO M P
7
C9
2200pF
R3
24k
Q1B
APM7312
C1
1uF
D1
1N4148
L4
3.3uH
U1
APW 7037
D2
1N4148
C2
1uF
Q2
APM2300A
Shutdown
R4
3
D3
1N4148
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
6
Typical Applications (Cont.)
3. LCD Monitor Application Circuit
V
IN
9V ~ 22V
V
OU T
5V / 0.2~ 5 A
C8
0.1uF
C3
0.1uF
C6
1uF
C5
470uF
C4
47uF
C7,C10
2 x 470uF
R1
3k
R2
1k
Q 1A
A P M 7313
L3
1uH
HDRV
5
LDRV
3
V C
6
FB
1
V CC
2
G ND
4
S S
8
CO M P
7
C9
2200pF
R3
24k
Q 1B
A P M 7313
C1
1uF
D1
1N4148
L4
50uH
U1
A P W 7037
D2
1N4148
C2
1uF
R4
3
U2
A P L431
R5
18k
R6
10k
R7 1k
R9
12
Q 2
2N3904
R8 0
C11
1uF
R10
12
C12
0.1uF
E x tra Circ uit for V IN> 15V A pplic ation
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
7
Package Information
Millimet ers
Inches
Dim
Min.
Max.
Min.
Max.
A
1.35
1.75
0.053
0.069
A1
0.10
0.25
0.004
0.010
D
4.80
5.00
0.189
0.197
E
3.80
4.00
0.150
0.157
H
5.80
6.20
0.228
0.244
L
0.40
1.27
0.016
0.050
e1
0.33
0.51
0.013
0.020
e2
1.27BSC
0.50BSC
φ 1
8
°
8
°
H
E
e1
e2
0.015X45
D
A
A1
0.004max.
1
L
SOP-8 pin ( Reference JEDEC Registration MS-012)
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
8
Millimeters
Inches
Dim
Min.
Max.
Min.
Max.
A
1.2
0.047
A1
0.00
0.15
0.000
0.006
A2
0.80
1.05
0.031
0.041
b
0.19
0.30
0.007
0.012
D
2.9
3.1
0.114
0.122
e
0.65 BSC
0.026 BSC
E
6.40 BSC
0.252 BSC
E1
4.30
4.50
0.169
0.177
L
0.45
0.75
0.018
0.030
L1
1.0 REF
0.039REF
R
0.09
0.004
R1
0.09
0.004
S
0.2
0.008
φ1
0
°
8
°
0
°
8
°
φ2
12
° REF
12
° REF
φ3
12
° REF
12
° REF
L
(L1)
( 3)
S
( 2)
0.25
GAUGE
PLANE
1
b
D
e
2 x E / 2
8
1 2
e/2
E1
E
7
A1
A2
A
TSSOP-8
Package Information
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
9
Reflow Condition
(IR/Convection or VPR Reflow)
Physical Specifications
Pre-heat temperature
183 C
Peak temperature
Time
°
temperature
Classification Reflow Profiles
Convection or IR/
Convection
VPR
Average ramp-up rate(183
°C to Peak)
3
°C/second max.
10
°C /second max.
Preheat temperature 125 ± 25
°C)
120 seconds max
Temperature maintained above 183
°C
60 – 150 seconds
Time within 5
°C of actual peak temperature 10 –20 seconds
60 seconds
Peak temperature range
220 +5/-0
°C or 235 +5/-0°C 215-219°C or 235 +5/-0°C
Ramp-down rate
6
°C /second max.
10
°C /second max.
Time 25
°C to peak temperature
6 minutes max.
Package Reflow Conditions
pkg. thickness
≥≥≥≥ 2.5mm
and all bgas
pkg. thickness < 2.5mm and
pkg. volume
≥≥≥≥ 350 mm³
pkg. thickness < 2.5mm and pkg.
volume < 350mm³
Convection 220 +5/-0
°C
Convection 235 +5/-0
°C
VPR 215-219
°C
VPR 235 +5/-0
°C
IR/Convection 220 +5/-0
°C
IR/Convection 235 +5/-0
°C
Terminal Material
Solder-Plated Copper (Solder Material : 90/10 or 63/37 SnPb)
Lead Solderability
Meets EIA Specification RSI86-91, ANSI/J-STD-002 Category 3.
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
10
Reliability test program
Test item
Method
Description
SOLDERABILITY
MIL-STD-883D-2003
245
°C , 5 SEC
HOLT
MIL-STD-883D-1005.7
1000 Hrs Bias @ 125
°C
PCT
JESD-22-B, A102
168 Hrs, 100 % RH , 121
°C
TST
MIL-STD-883D-1011.9
-65
°C ~ 150°C, 200 Cycles
ESD
MIL-STD-883D-3015.7
VHBM > 2KV, VMM > 200V
Latch-Up
JESD 78
10ms , I
tr
> 100mA
Carrier Tape & Reel Dimensions
A
J
B
T2
T1
C
t
Ao
E
W
Po
P
Ko
Bo
D1
D
F
P1
Application
A
B
C
J
T1
T2
W
P
E
330
±1
62
± 1.5
12.75
+0.15
2 + 0.5
12.4 +0.2
2
± 0.2
12 + 0.3
- 0.1
8
± 0.1
1.75
± 0.1
F
D
D1
Po
P1
Ao
Bo
Ko
t
SOP-8
5.5
± 0.1 1.55 ±+0.1 1.55+0.25 4.0 ± 0.1 2.0 ± 0.1 6.4 ± 0.1 5.2± 0.1
2.1
± 0.1 0.3±0.013
Application
A
B
C
J
T1
T2
W
P
E
330
± 1
62 +1.5
12.75+
0.15
2 + 0.5
12.4
± 0.2 2 ± 0.2
12
± 0. 3
8
± 0.1
1.75
±0.1
F
D
D1
Po
P1
Ao
Bo
Ko
t
TSSOP-8
5.5
± 0. 1 1.5 + 0.1 1.5 + 0.1 4.0 ± 0.1 2.0 ± 0.1 7.0 ± 0.1 3.6 ± 0.3 1.6 ± 0.1 0.3±0.013
(mm)
Copyright ANPEC Electronics Corp.
Rev. A.4 - May, 2003
APW7037/A
www.anpec.com.tw
11
Cover Tape Dimensions
Customer Service
Anpec Electronics Corp.
Head Office :
5F, No. 2 Li-Hsin Road, SBIP,
Hsin-Chu, Taiwan, R.O.C.
Tel : 886-3-5642000
Fax : 886-3-5642050
Taipei Branch :
7F, No. 137, Lane 235, Pac Chiao Rd.,
Hsin Tien City, Taipei Hsien, Taiwan, R. O. C.
Tel : 886-2-89191368
Fax : 886-2-89191369
Application
Carrier Width
Cover Tape Width
Devices Per Reel
SOP- 8
12
9.3
2500
TSSOP- 8
12
9.3
2500