STMICROELECTRONICS TDA7278

TDA7278
HIGH-EFFICIENCY CD ACTUATOR DRIVER
WIDE OPERATIVE SUPPLY RANGE (1.6 to
5V) LOW VOLTAGE OPERATION CAPABILITY
4 LOAD DRIVING VOLTAGES PWM REGULATED (STEP DOWN FROM BATTERY)
LOW ON RESISTANCE H BRIDGES
(2 x 1.6Ω MAX + 2 x 2.5Ω MAX) FOR:
– FOCUS AND TRACKING ACTUATORS
– SLEDGE AND SPINDLE MOTORS
SYNCHRONIZABLE SAWTOOTH OSCILLATOR
CONFIGURABLE DC/DC CONVERTER FOR
ADJUSTABLE MAIN POWER SUPPLY, WITH
LOW ON RESISTANCE (0.4Ω MAX) SWITCH
GENERAL ENABLE INPUT
ADJUSTABLE WATCH DOG AND DELAYED
POWER ON RESET FUNCTIONS
PQFP44
ADJUSTABLE COMPARATORS FOR BATTERY LOW AND BATTERY EMPTY DETECTION
March 1997
H OUT 2B
ERROR 1
ERROR 2
BEMP
BLOW
VCON
VREF(2)
VREF(1)
ERROR 4
ERROR 3
H OUT 4B
PIN CONNECTION
44
43
42
41
40
39
38
37
36
35
34
FLIN 4
VBAT
4
30
VBAT
FLIN 1
5
29
FLIN 3
GND
6
28
GND
H OUT 1A
7
27
H OUT 3A
H IN 1
8
26
H IN 3
H OUT 1B
9
25
H OUT 3B
OUT
10
24
ENABLE
VHIGH
11
23
SYNC
12
13
14
15
16
17
18
19
20
21
22
STCAP
31
WDINP
3
CRES
FLIN 2
RESET
H OUT 4A
VBG
32
OUT2
2
OUT1
H OUT 2A
VCPU
H IN 4
IRC
33
INP
1
SSCAP
H IN 2
D94AU112A
1/15
TDA7278
ABSOLUTE MAXIMUM RATINGS (25°C)
Pin Name
Min
Max
Unit
HIN 1, HIN 2, HIN 3, HIN 4
-0.4
8
V
HOUT 1A, HOUT 2A, HOUT 3A, HOUT 4A, HOUT 1B, HOUT 2B, HOUT 3B,
HOUT 4B
-0.4
8
V
FLIN 1, FLIN 2, FLIN 3, FLIN 4
-0.4
10
V
ERROR 1, ERROR 2, ERROR 3, ERROR 4,
-0.4
7
V
VBAT
-0.4
8
V
VREF 1, V REF 2
-0.4
7
V
BLOW, BEMP, VCON
-0.4
7
V
OUT, VHIGH
-0.4
16
V
OUT 2
-0.4
8
V
OUT 1
-0.4
16
V
SSCAP, IRC, INP
-0.4
7
V
VCPU
-0.4
7
V
VBG, RESET, CRES, WDINP, STCAP, SYNC
-0.4
7
V
EN
-0.4
8
V
* Pin 1, 8, 12, 14, 20, 26 and 33 are ESD sensitive (max. voltage ±1KV)
THERMAL DATA
Symbol
Top
Tj
T j-amb
2/15
Parameter
Value
Unit
–25 to 70
°C
Max. Junction Temperature
100
°C
Thermal Resistance Junction to Ambient
70
°C/W
Operating Temperature range
TDA7278
PIN FUNCTIONS
No
Name
21
WDINP
Watch dog input - AC coupled to WD µcontroller output
(Disabled when connected to GND)
20
CRES
Start up reset control for µC & watch dog time constant
Function
19
RESET
Reset output command to µC (open collector)
41
BEMP
Battery empty comparator input
40
BLOW
Battery low comparator input
39
VCON
Battery level control output
VCON = Z VBEMP > VBCON > VBG
VCON = 1 VBEMP > VBG > VBLOW
VCON = 0 VBG > VBEMP > VBLOW
24
ENABLE
18
VBG
12
SSCAP
Soft start capacitor
16
OUT 1
Switching transistor terminal high
17
OUT 2
Switching transistor terminal low
15
VCPU
Regulated voltage
14
IRC
Error amplifier output
13
INP
Error amplifier inverting input
11
VHIGH
10
OUT
22
STCAP
Sawtooth toth
23
SYNC
Oscillator synchronizing input
4, 30
VBAT
Power supply voltage
6, 28
GND
Power ground
38
VREF 2
37
VREF 1
Reference input voltage
5
FLIN 1
Switching Output
7
HOUT 1A
General Enable Input (active Low)
Regulated Voltage
Switching transistor output
H bridge positive output
HIN 1
HOUT 1B
H bridge negative output
43
ERROR 1
Error input
FLIN 3
HOUT 3A
Regulated voltage H bridge supply
HIN 3
25
HOUT 3B
H bridge negative output
35
ERROR 3
Error input
3
FLIN 2
HOUT2A
VCPU DC-DC
converter
Vhigh Boost DC-DC
Converter
Oscillator
Focus actuator step
down converter
& H bridge
Switching Output
H bridge positive output
26
2
Band Gap Reference
Buffered reference output voltage
9
27
Battery control circuit
Reference voltage capacitor
8
29
Watch dog & reset
circuit
Regulated voltage H bridge supply
Tracking actuator
step down converter
& H bridge
Switching output
H bridge positive output
1
HIN 2
44
HOUT 2B
H bridge negative output
Regulated voltage H bridge supply
42
ERROR 2
Error input
Spindle motor step
down converter
& H bridge
3/15
TDA7278
ELECTRICAL CHARACTERISTICS (Tamb = 25°C, VBAT = 1.6V unless otherwise specified)
Symbol
VBAT
Parameter
Power Supply
(Tamb = 25 to 70°C)
Power Supply
(Tamb = 25 to 60°C)
VHIGH
VCPU (adj)
VBG
AV
K
ZIN
Current Consumption from
VCPU (1)
Current Consumption from
VBAT (3)
Leakage Current in standby condition
Output Voltages
RON ofDC/DC Converter Switch
Max Output Current from
VCPU
Voltage Ripple on VCPU
Oscillator - free freq.
- sync. freq
- ∆ free freq.
H_bridge
- Ron, actuators (CH 1,3)
- Ron, motors (CH 2,4)
PWM Circuit
- Ron, actuators
- Ron, motors
Reference Voltage
Load Regulation
Line Regulation
Bridge gain
Reset Time Coefficient
Error Impedance Inputs
VREF2 Load Regulation
VREF1 Impedance
WINDIP Impedance
BEMP & BLOW
intervention threshold
RESET Voltage Saturation
VCON Voltage Saturation
Test Condition
Config. in fig. 3a: VCPU <4V
Config. in fig. 3a: VCPU >4V
Config. in fig. 3b
Config. in fig. 3c
Stand-by condition
Config. in fig 3a
Config. in fig. 3a
Config. in fig. 3b
Config. in fig. 3c
Stand-by condition
Config. in fig 3a
VCPU = 5V
Min.
1.6
1.6
VCPU +0.3
1.6
Typ.
Max.
VCPU
4
4
4
Unit
V
V
V
V
4
VCPU
5
5
V
V
V
V
5.5
5
V
mA
1.5
mA
1.6
VCPU +0.3
1.6
VBAT = 5V
VBAT +4
2.4
I = 1A
VCPU < 4.5V Config. fig 3a
STCAP = 470pF
.
VBAT = 1.6 to 5V
I = 100mA
VBAT +7
0.25
µA
VBAT +12
5
0.4
V
V
Ω
mA
150
180
20
KHz
KHz
KHz
1.0
1.6
1.6
2.5
Ω
Ω
0.5
0.8
1.28
0.8
1.25
1.34
30
30
4.5
17.2
Ω
Ω
V
mV
mV
200
80
I = 100mA
ILOAD =-10 to+10µA;
VBAT = 1.6 to 5V
From Error to HIN
note 2
ILOAD =-1 to+1mA
1.22
-30
2.8
7.4
26
–30
0.55
ILOAD =-100µA
ILOAD =-100µA
ILOAD =100µA
3.6
11
40
30
750
30
0.65
0.75
200
200
VCPU-200
(1): all the 4 PWM outputs switched off.
(2) TRESET = width of the Reset pulse on pin 19 = K ⋅ C, where C is the capacitance on pin 20 (CRES).
To avoid reset, the frequency of watch dog pulses must be greater than (3 ⋅ TRESET)-1
(3) All the 4 PWM output switched OFF, auxiliary and main DC/DC converters polarized but not switching
4/15
20
msec/µF
kΩ
mV
kΩ
kΩ
V
mV
mV
mV
TDA7278
VBAT
4
30
ST CAP
VREF (2)
22
37
ERROR 1
VBAT
23
VREF (1)
SYNC
ERROR 3
Figure 1: Block Diagram.
35
43
DRIV
OSCILL
5
38
ER
S
-
R
+
VHIGH
8
VHIGH
VHIGH
DRIV
-
10
FL IN 1
Q
11
+
OUT
VBAT
VHIGH
H IN 1
DRIV
7
9
H OUT 1A
H OUT 1B
V bg
INP
IRC
13
14
DRIV
29
ER
VCPU
OUT1
SSCAP
S
-
R
+
15
VHIGH
+
+
VHIGH
VHIGH
DRIV
-
Vbg
27
25
17
VBAT
3
REFERENCE
and
THERMAL
24
Vbg
ER
S
-
R
+
+
DRIV
H IN 2
DRIV
2
20
44
H OUT 2A
H OUT 2B
19
CONTROL
WD INP
VHIGH
VHIGH
-
FL IN 2
Q
1
RESET
H OUT 3B
DRIV
18
Vbg/2
CRES
H OUT 3A
12
VHIGH
ENABLE
H IN 3
DRIV
VBAT
VBG
FL IN 3
Q
26
16
DRIV
OUT2
VBAT
VHIGH
Vbg
21
VBAT
VHIGH
DRIV
31
ER
40
+
VCON
39
S
-
R
+
VCPU
33
-
+
+
-
Vbg/2
VHIGH
VHIGH
DRIV
32
34
6
28
GND
42
H IN 4
DRIV
-
GND
FL IN 4
Q
Vbg/2
H OUT 4A
H OUT 4B
36
ERROR 4
BLOW
41
ERROR 2
BEMP
D94AU078B
5/15
TDA7278
SYNC
23
22
VREF (2)
38
4
37
30
ERROR 1
VREF (1)
VBAT
ST CAP
ERROR 3
Figure 2: Test Circuit
35
43
VBAT
VHIGH
OSCILL
DRIV
5
470pF
ER
10µF
S
-
R
+
VHIGH
Q
100µH
11
8
VBAT
+
47µH
10
DRIV
10µF
DRIV
OUT
10µF
AUXIL.
STEP UP
FEEDBAKC
&
COMPENSATION
NETWORK
(see fig.4)
13
H OUT 1A
9
H OUT 1B
IRC
14
DRIV
29
S
-
R
+
OUT1
FOCUS
ACTUATOR
VBAT
VHIGH
ER
STEP LP
or
STEP DOWN
STRUCTURE
(see fig.3)
7
V bg
INP
VCPU
H IN 1
VHIGH
VHIGH
-
FL IN 1
100µH
Q
26
15
16
VHIGH
+
DRIV
-
OUT2
H IN 3
VHIGH
VHIGH
DRIV
-
FL IN 3
10µF
DRIV
Vbg
27
H OUT 3A
25
H OUT 3B
TRACKING
ACTUATOR
+
17
SSCAP
12
2µF
VBAT
VHIGH
VBG
18
DRIV
VBAT
3
100nF
ENABLE
REFERENCE
and
THERMAL
24
ER
Vbg
S
-
R
+
100µH
Q
1
+
CRES
20
DRIV
10µF
DRIV
1µF
RESET
VBAT
BEMP
BLOW
H OUT 2B
31
FL IN 4
M SPINDLE
MOTOR
VBAT
VHIGH
21
DRIV
41
ER
40
39
S
-
R
+
+
100µH
Q
33
Vbg/2
+
-
+
-
Vbg/2
H IN 4
VHIGH
VHIGH
DRIV
10µF
DRIV
-
32
H OUT 4A
34
H OUT 4B
M
42
36
ERROR 4
GND
28
ERROR 2
6
6/15
H OUT 2A
Vbg
VCPU
VCON
2
44
19
CONTROL
WD INP
H IN 2
VHIGH
VHIGH
-
FL IN 2
D94AU111A
SLEDGE
MOTOR
TDA7278
Figure 3: DC – DC Converter Configuration.
VCPU
15
VBAT
VHIGH
L
16
OUT 1
DRIV
C
OUT 2
17
D94AU081B
a) step-up
VCPU
15
VBAT
VHIGH
16
OUT 1
DRIV
L
OUT 2
17
C
D94AU082B
b) step-down
VCPU
15
VBAT
VHIGH
C
16
OUT 1
DRIV
OUT 2
17
D94AU083B
c) with transformer
7/15
TDA7278
Figure 4: DC – DC Converter: Feedback and Compensation Networks.
VCPU SETTING
RESISTOR
INP
R4
13
Cf
R
14
IRC
Vbg
VCPU
15
D94AU113A
a) Dominant Pole Compensation
INP
R4
R3
C2
13
Cf
Rf
R2
14
IRC
-
VCPU
+
15
Vbg
D94AU114A
b) Extended Bandwidth 2 zero, 2 pole compensation
INP
R4
R3
Cf
C2
Rf
R2
14
-
IRC
VCPU
C1
13
15
+
Vbg
R1
D94AU115A
c) Extended Bandwidth 2 zero, 3 pole compensation
8/15
TDA7278
SUGGESTED VALUES FOR OUTPUT FILTER AND COMPENSATION NETWORK
DC- DC COVERTER
CONFIGURATIONS
OUTPUT FILTER (see fig. 3)
COMPENSATION (see fig. 4)
a) DOMINANT POLE
R = 50KΩ
Cf = 47nF
R4 = 35KΩ
b) 2 ZERO, 2 POLE
L = 47µH
C = 47µF
STEP-DOWN
R2 = 11.18KΩ
R3 = 100 KΩ
C2 = 936pF
Rf = 16.65KΩ
Cf = 5.6nF
R4 = 70KΩ
a) DOMINANT POLE
R = 100KΩ
Cf = 220nF
R4 = 70KΩ
c) 2 ZERO, 3 POLE
L = 47µH
C = 47µF
R1 = 500Ω
C1 = 18nF
R2 = 20.8KΩ
R3 = 250KΩ
C2 = 636pF
Rf = 21.4KΩ
Cf = 7.44nF
R4 = 200KΩ
STEP-UP
AND
TRANSFORMER
c) 2 ZERO, 3 POLE
R1 = 500Ω
C1 = 18nF
R2 = 10.4KΩ
R3 = 250KΩ
C2 = 318pF
Rf = 21.4KΩ
Cf = 3.7nF
R4 = 200KΩ
L = 11µH
C = 47µF
PINS: 1, 2, 44
PINS: 8, 7,9
12V
1
12V
VHIGH
8
+
2
VHIGH
+
7
44
VHIGH
9
D96AU447A
VHIGH
D96AU448A
9/15
TDA7278
PINS: 25, 26, 27
PINS: 32, 33, 34
12V
12V
VHIGH
26
VHIGH
33
+
27
+
32
VHIGH
25
VHIGH
34
D96AU449A
PIN: 3
D96AU450A
PINS: 5
12V
12V
VBAT
VBAT
VHIGH
4
VHIGH
4
5
3
VHIGH
VHIGH
D96AU451
PIN: 29
D96AU452
PINS: 31
12V
12V
VBAT
30
VBAT
VHIGH
30
29
31
VHIGH
VHIGH
D96AU453
10/15
VHIGH
D96AU454
TDA7278
PINS: 35
PIN: 36
VCPU
35
VCPU
36
+
7V
+
7V
38
38
D96AU465
D96AU466
PIN: 43
PIN: 42
VCPU
-
VCPU
42
43
+
7V
+
7V
38
38
D96AU467
PIN: 18
D96AU468
PINS: 19
VBAT
VBAT
19
18
+
-
7V
REFERENCE
7V
D96AU459
D96AU458
11/15
TDA7278
PINS: 21
PINS: 20
VCPU
VCPU
1.8
+
20
7V
VCPU VCPU
0.7
-
VCPU
VCPU
+
-
+
21
-
7V
-
VCPU
0.6
VCPU
+
+
-
D96AU460A
D96AU461A
PIN: 22
PIN: 23
VBAT
VBAT
1.3
+
VCPU
22
VBAT
7V
0.6
+
-
23
7V
D96AU463
VBAT
0.2
+
-
D96AU462
PINS: 10, 11
PIN: 24
17V
VBAT
VBAT
VBAT
11
+
24
10
12V
D96AU464A
D96AU474
12/15
TDA7278
PINS: 12, 13, 14
PINS: 16, 17
VBAT
VBAT
VBAT
16
13
+
VBG
12
17
17V
14
D96AU476
7V
D96AU475
PINS: 37, 38
PIN: 39
VCPU
VCPU
37
+
VCPU
-
39
38
7V
7V
D96AU469
D96AU470A
PINS: 40, 41
VBG
VCPU
+
40
5V
VCPU
+
7V
41
5V
D96AU471
13/15
TDA7278
PQFP44 (10x10) PACKAGE MECHANICAL DATA
mm
DIM.
MIN.
inch
TYP.
MAX.
A
MIN.
TYP.
MAX.
2.45
A1
0.25
A2
1.95
B
0.096
0.010
2.00
2.10
0.077
0.079
0.30
0.45
0.012
0.018
c
0.13
0.23
0.005
0.009
D
12.95
13.20
13.45
0.51
0.52
0.53
D1
9.90
10.00
10.10
0.390
0.394
0.398
D3
8.00
0.315
e
0.80
0.031
0.083
E
12.95
13.20
13.45
0.510
0.520
0.530
E1
9.90
10.00
10.10
0.390
0.394
0.398
E3
8.00
L
0.65
0.315
0.80
L1
0.95
0.026
0.031
1.60
0.037
0.063
K
0°(min.), 7°(max.)
D
D1
A
D3
A2
A1
23
33
22
34
0.10mm
.004
B
E
E1
B
E3
Seating Plane
12
44
11
1
C
L
L1
e
K
PQFP44
14/15
TDA7278
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned
in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as criticalcomponents in life support devices or systems without express
written approval of SGS-THOMSON Microelectronics.
 1997 SGS-THOMSON Microelectronics All Rights Reserved
SGS-THOMSON Microelectronics GROUP OF COMPANIES
Australia - Brazil - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands - Singapore Spain - Sweden - Switzerland - Taiwan - Thaliand - United Kingdom - U.S.A.
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