GMT G1420

Global Mixed-mode Technology Inc.
G1420
2W Stereo Audio Amplifier
Features
General Description
„
G1420 is a stereo audio power amplifier in 24pin
TSSOP thermal pad package. It can drive 1.8W continuous RMS power into 4Ω load per channel in
Bridge-Tied Load (BTL) mode at 5V supply voltage. Its
THD is smaller than 1% under the above operation
condition. To simplify the audio system design in the
notebook application, G1420 supports the Bridge-Tied
Load (BTL) mode for driving the speakers, Single-End
(SE) mode for driving the headphone. G1420 can
mute the output when Mute-In is activated. For the low
current consumption applications, the SHDN mode is
supported to disable G1420 when it is idle. The current
consumption can be further reduced to below 5µA.
„
„
„
„
„
Depop Circuitry Integrated
Output Power at 1% THD+N, VDD=5V
--1.8W/CH (typical) into a 4Ω Load
--1.2W/CH (typical) into a 8Ω Load
Bridge-Tied Load (BTL), Single-Ended (SE)
Stereo Input MUX
Mute and Shutdown Control Available
Surface-Mount Power Package
24-Pin TSSOP-P
Applications
„
Stereo Power Amplifiers for Notebooks or
Desktop Computers
„ Multimedia Monitors
„ Stereo Power Amplifiers for Portable Audio
Systems
G1420 also supports two input paths, that means two
different gain loops can be set in the same PCB and
choosing either one by setting HP/ LINE pin. It enhances the hardware designing flexibility.
Ordering Information
ORDER
NUMBER
ORDER NUMBER
(Pb free)
TEMP.
RANGE
PACKAGE
G1420F31U
G1420F31Uf
-40°C to +85°C
TSSOP-24 (FD)
Note: F3: TSSOP-24 (FD)
U: Tape & Reel
Pin Configuration
G1420
GND/HS
GND/HS
1
24
TJ
LOUT+
2
3
23
NC
22
ROUT+
LLINEIN
4
21
RLINEIN
LHPIN
5
20
RHPIN
LBYPASS
6
19
RBYPASS
LVDD
18
RVDD
SHUTDOWN
7
8
17
NC
MUTE OUT
9
16
HP/LINE
LOUT- 10
MUTE IN 11
15
14
ROUTSE/BTL
GND/HS 12
13
GND/HS
Thermal
Pad
14
Top View
TSSOP-24 (FD)
Bottom View
Note: Recommend connecting the Thermal Pad to the GND for excellent power dissipation.
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
1
G1420
Global Mixed-mode Technology Inc.
Absolute Maximum Ratings
Power Dissipation (1)
TA ≤ 25°C…………………………………………..2.7W
TA ≤ 70°C…………………………………………..1.7W
TA ≤ 85°C………………….……………………….1.4W
Electrostatic Discharge, VESD
Human body mode..…………………….-3000 to 3000(2)
Supply Voltage, VCC…………………..…..…….……...6V
Operating Ambient Temperature Range
TA…….…………………………….……….40°C to +85°C
Maximum Junction Temperature, TJ…….…….…150°C
Storage Temperature Range, TSTG……-65°C to+150°C
Reflow Temperature (soldering, 10sec)…………260°C
Note:
(1)
: Recommended PCB Layout
(2)
: Human body model : C = 100pF, R = 1500Ω, 3 positive pulses plus 3 negative pulses
Electrical Characteristics
DC Electrical Characteristics, TA=+25°C
PARAMETER
SYMBOL
CONDITIONS
VDD =3.3V
Supply Current
IDD
VDD = 5V
DC Differential Output Voltage
Supply Current in Mute Mode
IDD in Shutdown
VO(DIFF)
MIN
TYP
MAX
Stereo BTL
---
7
13
Stereo SE
Stereo BTL
-----
3.5
8
8
16
-----
4
5
10
50
8
16
4
2
10
5
Stereo SE
VDD = 5V,Gain = 2
IDD(MUTE)
VDD = 5V
ISD
VDD = 5V
Stereo BTL
Stereo SE
-----
UNIT
mA
mV
mA
µA
(AC Operation Characteristics, VDD = 5.0V, TA=+25°C, RL = 4Ω, unless otherwise noted)
PARAMETER
Output power (each channel) see Note
SYMBOL
P(OUT)
Total harmonic distortion plus noise
THD+N
Maximum output power bandwidth
BOM
Phase margin
Power supply ripple rejection
Mute attenuation
Channel-to-channel output separation
Line/HP input separation
BTL attenuation in SE mode
Input impedance
Signal-to-noise ratio
Output noise voltage
PSRR
MIN
TYP
MAX
THD = 1%, BTL, RL = 4Ω
CONDITIONS
---
1.8
---
THD = 1%, BTL, RL = 8Ω
THD = 10%, BTL, RL = 4Ω
-----
1.12
2
-----
THD = 10%, BTL, RL = 8Ω
THD = 1%, SE, RL = 4Ω
THD = 1%, SE, RL = 8Ω
THD = 10%, SE, RL = 4Ω
THD = 10%, SE, RL L = 8Ω
-----------
1.4
500
320
650
400
-----------
THD = 0.5%, SE, RL = 32Ω
PO = 1.6W, BTL, RL = 4Ω
PO = 1W, BTL, RL = 8Ω
PO = 75mW, SE, RL = 32Ω
VI = 1V, RL = 10KΩ, G = 1
-----------
90
500
150
20
10
-----------
G = 1, THD = 1%
RL = 4Ω, Open Load
-----
20
60
-----
kHz
°
f = 120Hz
-----
75
85
-----
dB
dB
f = 1kHz
82
80
85
2
90
-----------
dB
dB
dB
MΩ
PO = 500mW, BTL
-----------
Output noise voltage
---
55
---
µV (rms)
ZI
Vn
UNIT
W
mW
m%
dB
Note :Output power is measured at the output terminals of the IC at 1kHz.
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
2
G1420
Global Mixed-mode Technology Inc.
(AC Operation Characteristics, VDD = 3.3V, TA=+25°C, RL = 4Ω, unless otherwise noted)
PARAMETER
Output power (each channel) see Note
Total harmonic distortion plus noise
Maximum output power bandwidth
Phase margin
Power supply ripple rejection
Mute attenuation
Channel-to-channel output separation
Line/HP input separation
BTL attenuation in SE mode
Input impedance
Signal-to-noise ratio
Output noise voltage
SYMBOL
P(OUT)
THD+N
BOM
PSRR
CONDITIONS
THD = 1%, BTL, RL = 4Ω
THD = 1%, BTL, RL = 8Ω
THD = 10%, BTL, RL = 4Ω
THD = 10%, BTL, RL = 8Ω
THD = 1%, SE, RL = 4Ω
THD = 1%, SE, RL = 8Ω
THD = 10%, SE, RL = 4Ω
THD = 10%, SE, RL L = 8Ω
THD = 0.5%, SE, RL = 32Ω
PO = 1.6W, BTL, RL = 4Ω
PO = 1W, BTL, RL = 8Ω
PO = 75mW, SE, RL = 32Ω
VI = 1V, RL = 10KΩ, G = 1
G = 1, THD 1%
RL = 4Ω, Open Load
f = 120Hz
f = 1kHz
ZI
Vn
PO = 500mW, BTL
Output noise voltage
MIN
TYP
MAX
-----------------------------------------------
0.8
0.5
1
0.6
230
140
290
180
43
270
100
20
10
20
60
75
85
80
80
85
2
90
55
-----------------------------------------------
UNIT
W
mW
m%
kHz
°
dB
dB
dB
dB
dB
MΩ
dB
µV (rms)
Note :Output power is measured at the output terminals of the IC at 1kHz.
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
3
G1420
Global Mixed-mode Technology Inc.
Typical Characteristics
Table of Graphs
FIGURE
THD +N Total Harmonic Distortion Plus
Noise
Output Noise Voltage
vs Output Power
vs Frequency
vs Frequency
1,3,6,9,10,13,16,19,22,25,28,31
2,4,5,7,8,11,12,14,15,17,18,20,21,23,24,26,27,29,30,32,33
34,35
Supply Ripple Rejection Ratio
Crosstalk
vs Frequency
vs Frequency
36,37
38,39,40,41
IDD
Closed Loop Response
Supply Current
PO
Output Power
vs Frequency
vs Supply Voltage
vs Load Resistance
42,43,44,45
46
47,48
PD
Power Dissipation
vs Load Resistance
vs Output Power
49,50
51,52,53,54
Vn
Total Harmonic Distortion Plus
Noise vs Output Power
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
10
5
5
20kHz
2
2
1
Po=1.8W
1
1kHz
0.5
0.5
%
%
0.2
0.1
0.2
0.1
20 Hz
VDD=5V
RL=3Ω
BTL
0 .05
0 .02
0 .01
3m
5m
10m
20m
5 0m
1 00m
20 0m
500 m
1
VDD=5V
RL=3Ω
BTL
Av=-2V/V
Po=1.5W
0 .05
0 .02
2
0 .01
20
3
50
10 0
2 00
5 00
1k
W
Hz
Figure 1
Figure 2
Total Harmonic Distortion Plus
Noise vs Output Power
2k
5k
10 k
20k
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
10
5
5
Av=-4V/V
20kHz
2
2
1
1
1kHz
0.5
Av=-2V/V
0.5
%
%
0.2
0.2
0.1
0.1
VDD=5V
RL=4Ω
BTL
20 Hz
0 .05
0 .02
0 .01
3m
5m
10m
20m
5 0m
1 00m
20 0m
500 m
1
VDD=5V
RL=4Ω
BTL
Po=1.5W
Av=-1V/V
0 .05
0 .02
2
0 .01
20
3
50
10 0
2 00
5 00
1k
W
Hz
Figure 3
Figure 4
2k
5k
10 k
20k
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
4
G1420
Global Mixed-mode Technology Inc.
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Power
10
5
2
1
10
VDD=5V
RL=4Ω
BTL
Av=-2V/V
VDD=5V
RL=8Ω
BTL
Av=-2V/V
5
Po=1.5W
20kHz
2
1
Po=0.25W
0.5
0.5
%
%
0.2
0.2
Po=0.75W
0.1
0 .05
0 .05
0 .02
0 .02
0 .01
20
50
10 0
2 00
5 00
1k
2k
5k
10 k
1kHz
0.1
0 .01
3m
20k
20Hz
5m
10m
20m
5 0m
1 00m
Hz
Figure 5
1
1
2
3
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
2
500 m
Figure 6
Total Harmonic Distortion Plus
Noise vs Output Frequency
5
20 0m
W
10
VDD=5V
RL=8Ω
BTL
Av=-2V/V
5
2
Po=1W
1
Po=0.25W
0.5
VDD=5V
RL=8Ω
BTL
Po=1W
Av=-4V/V
0.5
%
Av=-2V/V
%
0.2
0.2
0.1
0.1
Po=0.5W
0 .05
0 .05
0 .02
Av=-1V/V
0 .02
0 .01
20
50
10 0
2 00
5 00
1k
2k
5k
10 k
0 .01
20
20k
50
10 0
2 00
5 00
1k
Hz
Hz
Figure 7
Figure 8
Total Harmonic Distortion Plus
Noise vs Output Power
2k
5k
10 k
20k
Total Harmonic Distortion Plus
Noise vs Output Power
10
10
5
5
20kHz
20kHz
2
2
1
1
1kHz
0.5
1kHz
0.5
%
%
0.2
0.1
0 .05
0 .02
0 .01
1m
0.2
0.1
VDD=3.3V
RL=3Ω
BTL
2m
5m
20Hz
0 .05
0 .02
1 0m
20 m
50 m
10 0m
2 00 m
500 m
0 .01
1m
1
VDD=3.3V
RL=4Ω
BTL
2m
5m
20Hz
1 0m
20 m
50 m
W
W
Figure 9
Figure 10
10 0m
2 00 m
500 m
1
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
5
G1420
Global Mixed-mode Technology Inc.
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
10
5
2
1
VDD=3.3V
RL=4Ω
BTL
Po=0.65W
5
Av=-4V/V
2
Av=-2V/V
1
VDD=3.3V
RL=4Ω
BTL
Av=-2V/V
Po=0.7W
0.5
0.5
%
%
Po=0.1W
0.2
0.2
0.1
0.1
Av=-1V/V
0 .05
0 .05
0 .02
0 .02
0 .01
20
50
10 0
2 00
5 00
1k
2k
5k
10k
0 .01
20
20k
Po=0.35W
50
100
2 00
5 00
1k
Total Harmonic Distortion Plus
Noise vs Output Power
Total Harmonic Distortion Plus
Noise vs Output Frequency
VDD=3.3V
RL=8Ω
BTL
20kHz
5
2
1
1
0.5
VDD=3.3V
RL=8Ω
BTL
Po=0.4W
Av=-4V/V
Av=-2V/V
0.5
%
%
1kHz
0.2
0.2
0.1
0.1
0 .05
0.05
Av=-1V/V
20Hz
0 .02
0.02
2m
5m
10m
20 m
50 m
10 0m
2 00m
500 m
0.01
20
1
50
10 0
200
500
W
2k
5k
10 k
Figure 13
Figure 14
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Power
20k
10
VDD=3.3V
RL=8Ω
BTL
Av=-2V/V
5
2
VDD=5V
RL=4Ω
SE
Po=0.4W
20kHz
1
0.5
0.5
%
%
Po=0.1W
0.2
0.2
0.1
1kHz
0.1
0 .05
0.05
Po=0.25W
100Hz
0 .02
0 .01
20
1k
Hz
10
1
20k
10
2
2
10k
Figure 12
5
5
5k
Figure 11
10
0 .01
1m
2k
Hz
Hz
0.02
50
10 0
2 00
5 00
1k
2k
5k
10k
0.01
1m
20k
Hz
2m
5m
1 0m
20m
50 m
10 0m
2 00 m
500 m
1
W
Figure 15
Figure 16
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
6
G1420
Global Mixed-mode Technology Inc.
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
5
2
1
10
VDD=5V
RL=4Ω
SE
Po=0.5W
5
Av=-4V/V
2
1
0.5
VDD=5V
RL=4Ω
SE
Av=-2V/V
Po=0.4W
0.5
Av=-2V/V
%
%
0.2
0.2
0.1
0.1
0 .05
Po=0.1W
0 .05
Av=-1V/V
Po=0.25W
0 .02
0 .02
0 .01
20
50
10 0
2 00
5 00
1k
2k
5k
10 k
0 .01
20
20k
50
10 0
2 00
5 00
Hz
2
Total Harmonic Distortion Plus
Noise vs Output Frequency
5
2
1
20kHz
VDD=5V
RL=8Ω
SE
Po=0.25W
0.5
Av=-2V/V
%
0.2
0.2
0.1
0.1
1kHz
0 .05
100Hz
2m
Av=-4V/V
0 .05
Av=-1V/V
0 .02
5m
1 0m
20 m
50 m
10 0m
2 00 m
500 m
0 .01
20
1
50
10 0
2 00
5 00
5k
10 k
Figure 20
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Power
20k
10
5
VDD=5V
RL=8Ω
SE
Av=-2
2
1
20kHz
0.2
Po=0.05W
%
%
0.1
0.2
0 .05
0.1
0 .02
Po=0.1W
0 .05
VDD=5V
RL=32Ω
SE
0.5
0.5
20Hz
0 .01
0.0 05
Po=0.25W
0 .02
0 .01
20
2k
Figure 19
10
1
1k
Hz
W
2
20k
10
VDD=5V
RL=8Ω
SE
%
5
10 k
Total Harmonic Distortion Plus
Noise vs Output Power
1
0 .01
1m
5k
Figure 18
0.5
0 .02
2k
Figure 17
10
5
1k
Hz
1kHz
0.0 02
50
10 0
2 00
5 00
1k
2k
5k
10 k
0.0 01
1m
20k
2m
5m
10 m
20 m
50m
10 0m
2 00m
W
Hz
Figure 21
Figure 22
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
7
G1420
Global Mixed-mode Technology Inc.
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
10
5
2
1
0.5
5
VDD=5V
RL=32Ω
SE
Po=75mW
2
1
Av=-4V/V
0.5
Po=25mW
0.2
0.2
%
VDD=5V
RL=32Ω
SE
%
0.1
Av=-2V/V
0 .05
0.1
0 .05
0 .02
0 .02
0 .01
0 .01
Po=50mW
0.0 05
0.0 05
Av=-1V/V
0.0 02
0.0 02
0.0 01
20
0.0 01
20
50
10 0
2 00
5 00
1k
2k
5k
10 k
20k
Po=75mW
50
10 0
2 00
5 00
2
Total Harmonic Distortion Plus
Noise vs Output Frequency
5
2
20kHz
1
VDD=3.3V
RL=4Ω
SE
Po=0.2W
Av=-4V/V
0.5
%
1kHz
0.2
0.2
0.1
0.1
0 .05
0 .05
100Hz
0 .02
2m
5m
1 0m
Av=-2V/V
Av=-1V/V
0 .02
20 m
50 m
10 0m
2 00 m
500 m
0 .01
20
1
50
10 0
2 00
5 00
1k
2k
5k
10 k
20k
Hz
W
Figure 25
Figure 26
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Power
10
10
R R
1
20k
10
VDD=3.3V
RL=4Ω ,SE
Av=-2
0.5
2
10 k
Total Harmonic Distortion Plus
Noise vs Output Power
%
5
5k
Figure 24
1
0 .01
1m
2k
Figure 23
10
5
1k
Hz
Hz
VDD=3.3V
RL=4Ω
SE
Av=-2
5
Po=50mW
2
VDD=3.3V
RL=8Ω ,SE
Av=-2
20kHz
1
0.5
0.5
%
%
0.2
0.2
Po=100mW
0.1
0.1
0 .05
0 .05
0 .02
0 .01
20
50
10 0
2 00
5 00
Po=150mW
0 .02
1k
0 .01
1m
2k
5k
10 k
20k
Hz
1kHz
100Hz
2m
5m
10 m
20 m
50m
10 0m
2 00m
W
Figure 27
Figure 28
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.5
Aug 04, 2005
8
G1420
Global Mixed-mode Technology Inc.
Total Harmonic Distortion Plus
Noise vs Output Frequency
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
10
5
2
1
5
VDD=3.3V
RL=8Ω
SE
Po=100mW
2
VDD=3.3V
RL=8Ω
SE
1
Av=-4V/V
Po=25mW
0.5
0.5
%
%
0.2
0.2
Av=-2V/V
0.1
Po=50mW
0.1
0 .05
0 .05
Av=-1V/V
0 .02
0 .01
20
50
10 0
2 00
5 00
1k
2k
5k
0 .02
10 k
0 .01
20
20k
Po=100mW
50
10 0
2 00
5 00
Figure 29
5
VDD=3.3V
RL=32Ω
SE
2
1kHz
1
0.5
20kHz
0.5
VDD=3.3V
RL=32Ω
SE
Po=30mW
0.2
%
%
0.2
Av=-4V/V
Av=-2V/V
0.1
0 .05
0.1
0 .02
20Hz
0 .05
0 .01
Av=-1V/V
0.0 05
0 .02
0.0 02
0 .01
1m
2m
5m
1 0m
2 0m
50 m
0.0 01
20
1 00m
50
10 0
2 00
5 00
Figure 31
5k
10 k
20k
Output Noise Voltage vs Frequency
10
10 0u
9 0u
VDD=3.3V
RL=32Ω
SE
8 0u
7 0u
6 0u
VDD=5V
BW=22Hz to 20kHz
RL=4Ω
5 0u
Po=10mW
4 0u
0.2
%
2k
Figure 32
Total Harmonic Distortion Plus
Noise vs Output Frequency
0.5
1k
Hz
W
1
20k
10
1
2
10 k
Total Harmonic Distortion Plus
Noise vs Output Frequency
10
5
5k
Figure 30
Total Harmonic Distortion Plus
Noise vs Output Power
2
2k
Hz
Hz
5
1k
0.1
V
Vo BTL
3 0u
Po=20mW
0 .05
0 .02
Vo SE
2 0u
0 .01
0.0 05
Po=30mW
0.0 02
0.0 01
20
50
10 0
2 00
5 00
1k
2k
5k
10 k
1 0u
20
20k
Hz
50
10 0
2 00
5 00
1k
2k
5k
10 k
20k
Hz
Figure 33
Figure 34
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G1420
Global Mixed-mode Technology Inc.
Supply Ripple Rejection Ratio vs Frequency
Output Noise Voltage vs Frequency
10 0u
9 0u
8 0u
7 0u
+0
T
VDD=3.3V
BW=22Hz to 20kHz
RL=4Ω
-10
-20
6 0u
5 0u
-30
Vo BTL
4 0u
V
VDD=5V
RL=4Ω
CB=4.7uF
-40
d
B
3 0u
-50
BTL
-60
2 0u
-70
Vo SE
-80
SE
-90
1 0u
20
50
1 00
2 00
5 00
1k
2k
5k
10k
-1 00
20
20k
50
1 00
2 00
Hz
10k
20k
5k
10k
20k
10 k
20k
-20
T
-25
VDD=3.3V
RL=4Ω
CB=4.7uF
-30
-35
-40
-45
-50
-40
d
B
5k
Crosstale vs Frequency
+0
-30
2k
Figure 36
Supply Ripple Rejection Ratio vs Frequency
-20
1k
Hz
Figure 35
-10
5 00
VDD=5V
Po=1.5W
RL=4Ω
BTL
-55
-50
d
B
BTL
-60
-60
-65
L to R
-70
-75
-70
-80
-80
-85
SE
-90
-90
R to L
-95
-1 00
20
50
1 00
2 00
5 00
1k
2k
5k
10k
-100
20
20k
50
100
200
Hz
Crosstale vs Frequency
-35
-40
-45
Crosstale vs Frequency
-30
-35
VDD=3.3V
Po=0.75W
RL=4Ω
BTL
-40
-45
-50
-55
-50
d
B
-60
-65
-70
L to R
R to L
-75
-80
-80
-85
-85
-90
R to L
-95
-100
20
-65
-70
-75
-90
VDD=5V
Po=75mW
RL=32Ω
SE
-60
-55
d
B
2k
Figure 38
-20
-30
1k
Hz
Figure 37
-25
500
L to R
-95
50
100
200
500
1k
2k
5k
10k
-1 00
20
20k
Hz
50
10 0
20 0
50 0
1k
2k
5k
Hz
Figure 39
Figure 40
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G1420
Global Mixed-mode Technology Inc.
Closed Loop Response
Crosstale vs Frequency
-30
-35
-40
-45
-50
-55
VDD=3.3V
Po=35mW
RL=32Ω
SE
-60
d
B
-65
R to L
-70
-75
-80
-85
-90
L to R
-95
-1 00
20
50
10 0
20 0
50 0
1k
2k
5k
10 k
20k
Hz
Figure 41
Figure 42
Closed Loop Response
Closed Loop Response
Figure 44
Figure 43
Closed Loop Response
Supply Current vs Supply Voltage
10
9
Supply Current(mA)
8
Stereo BTL
7
6
5
Stereo SE
4
3
2
1
0
3
Figure 45
4
5
Supply Voltage (V)
6
Figure 46
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G1420
Global Mixed-mode Technology Inc.
Output Power vs Supply Voltage
Output Power vs Supply Voltage
2.5
0.7
THD+N=1%
BTL
Each Channel
1.5
RL=3Ω
1
THD+N=1%
SE
Each Channel
0.6
RL=4Ω
Po-Output Power(W)
Po-Output Power (W)
2
RL=8Ω
0.5
0.5
RL=8Ω
0.4
RL=4Ω
0.3
0.2
RL=32Ω
0.1
0
0
2.5
3.5
4.5
5.5
6.5
2.5
3.5
4.5
Supply Voltage(V)
Supply Voltage (V)
Output Power vs Load Resistance
Output Power vs Load Resistance
2
0.7
THD+N=1%
BTL
Each Channel
VDD=5V
1.6
1.4
1.2
VDD=3.3V
1
VDD=5V
0.6
Po-Output Power(W)
1.8
Po-Output Power(W)
6.5
Figure 48
Figure 47
0.8
0.6
0.4
THD+N=1%
SE
Each Channel
0.5
0.4
0.3
0.2
0.1
0.2
0
VDD=3.3V
0
0
4
8
12
16
20
24
28
32
0
4
8
Load Resistance(Ω)
12
16
20
24
Load Resistance(Ω)
28
32
Figure 50
Figure 49
Power Dissipation vs Output Power
Power Dissipation vs Output Power
0.8
1.8
1.6
0.7
RL=3Ω
1.4
RL=3Ω
0.6
Power Dissipation(W)
Power Dissipation(W)
5.5
1.2
0.5
RL=4Ω
1
RL=4Ω
0.4
0.8
0.6
0.4
RL=8Ω
VDD=5V
BTL
Each Channel
0.3
RL=8Ω
0.2
VDD=3.3V
BTL
Each Channel
0.1
0.2
0
0
0
0.5
1
1.5
Po-Output Pow er(W)
2
0
2.5
0.25
0.5
Output Pow er(W)
0.75
1
Figure 52
Figure 51
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G1420
Global Mixed-mode Technology Inc.
Power Dissipation vs Output Power
Power Dissipation vs Output Power
0.16
0.35
0.14
RL=4Ω
Power Dissipation(W)
Power Dissipation(W)
0.3
0.25
0.2
0.15
RL=8Ω
0.1
0.05
RL=32Ω
VDD=5V
SE
Each Channel
0.2
0.6
0.12
RL=4Ω
0.1
RL=8Ω
0.08
0.06
VDD=3.3V
SE
Each Channel
0.04
0.02
0
RL=32Ω
0
0
0.4
Output Pow er(W)
0
0.8
Figure 53
0.05
0.1
0.15
0.2
Output Pow er (W)
0.25
0.3
Figure 54
Recommended Minimum Footprint
TSSOP-24 (FD)
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G1420
Global Mixed-mode Technology Inc.
Pin Description
PIN
NAME
1,12,13,24
2
GND/HS
TJ
O
3
4
LOUT+
LLINE IN
O
I
Left channel + output in BTL mode, + output in SE mode.
Left channel line input, selected when HP/ pin is held low.
5
LHP IN
I
Left channel headphone input, selected when HP/pin is held high.
6
7
8
LBYPASS
LVDD
SHUTDOWN
I
I
9
10
MUTE OUT
LOUT-
O
O
Connect to voltage divider for left channel internal mid-supply bias.
Supply voltage input for left channel and for primary bias circuits.
Shutdown mode control signal input, places entire IC in shutdown mode when held
high, IDD = 5µA.
Follows MUTE IN pin, provides buffered output.
Left channel - output in BTL mode, high impedance state in SE mode.
11
14
MUTE IN
I
Mute control signal input, hold low for normal operation, hold high to mute.
SE/ BTL
I
Mode control signal input, hold low for BTL mode, hold high for SE mode.
15
16
ROUT-
O
I
Right channel - output in BTL mode, high impedance state in SE mode.
MUX control input, hold high to select headphone inputs (5,20), hold low to select line
inputs (4,21).
I
Supply voltage input for right channel.
Connect to voltage divider for right channel internal mid-supply bias.
Right channel headphone input, selected when HP/pin is held high.
Right channel line input, selected when HP/pin is held low.
Right channel + output in BTL mode, + output in SE mode.
Recommend connecting the Thermal Pad to the GND for excellent power dissipation.
17,23
18
19
20
21
22
Thermal Pad
HP/ LINE
NC
RVDD
RBYPASS
RHP IN
RLINE IN
ROUT+
I/O
I
I
O
FUNCTION
Ground connection for circuitry, directly connected to thermal pad.
Source a current inversely to the junction temperature. This pin should be left unconnected during normal operation. For more information, see the junction temperature
measurement section of this document.
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G1420
Global Mixed-mode Technology Inc.
Block Diagram
20k
21
RLINEIN
20
RHPIN
19
RBYPASS
11
_
RIGHT
MUX
MUTEIN
9
MUTEOUT
8
SHUTDOWN
6
LBYPASS
5
LHPIN
4
LLINEIN
ROUT+
22
ROUT-
15
RVDD
18
+
HP/LINE
16
SE/BTL
14
TJ
2
LVDD
7
+
LOUT-
10
_
LOUT+
3
BIAS CIRCUITS
MODES CONTROL
CIRCUITS
LEFT
MUX
20k
Parameter Measurement Information
11
8
MUTEIN
SHUTDOWN
HP/LINE
16
SE/BTL
14
LVDD
7
RL 4/8/32ohm
6
LBYPASS
CB
4.7µF
CI
AC source
5
LHPIN
4
LLINEIN
LEFT
MUX
+
LOUT-
10
_
LOUT+
3
RI
RF
BTL Mode Test Circuit
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Global Mixed-mode Technology Inc.
Parameter Measurement Information (Continued)
11
8
6
MUTEIN
AC source
16
SE/BTL
14
LVDD
7
+
LOUT-
10
_
LOUT+
3
VDD
LBYPASS
CB
4.7µF
CI
HP/LINE
SHUTDOWN
5
LHPIN
4
LLINEIN
LEFT
MUX
RI
RL 32ohm
RF
SE Mode Test Circuit
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G1420
Global Mixed-mode Technology Inc.
Application Circuits
GND/HS
TJ
LOUT+
RFL
20KΩ
CIR
CFR
AUDIO SOURCE 1µF
LLINEIN
RIR
10KΩ
LHPIN
LBYPASS
RBYPASS
4.7µF
SHUTDWON
MUTE OUT
LOUTMUTE IN
GND/HS
1
24
2
23
3
22
4
21
5
20
6
7
19
G1420
18
8
17
9
16
10
15
11
14
12
13
GND/HS
NC
ROUT+
RIL
CIL
10KΩ
1µF
RLINEIN
RFL
RHPIN
20KΩ
CFL
AUDIO SOURCE
LVDD
RVDD
4.7µF
R
NC
CSR
4.7µF
100KΩ
COUTR
HP/LINE
220µF
ROUTR
SE/BTL
100KΩ
1KΩ
1
3
4
2
GND/HS
PHONOJACK
0.1µF
COUTR
220µF
1KΩ
Logical Truth Table
SE/ BTL
INPUTS
Mute In
HP/ LINE
Shutdown
OUTPUT
Mute Out
Input
X
Low
High
X
X
X
---High
High
High
-------
---High
High
X
X
X
Low
Low
Low
Low
Low
L/R Line
Low
High
Low
Low
Low
L/R HP
High
Low
Low
Low
Low
L/R Line
High
High
Low
Low
Low
L/R HP
AMPLIFIER STATES
L/R Out+
L/R Out---VDD/2
VDD/2
BTL
Output
BTL
Output
SE
Output
SE
Output
Mode
---VDD/2
---BTL
Output
BTL
Output
Mute
Mute
Mute
----
SE
----
SE
BTL
BTL
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Global Mixed-mode Technology Inc.
Application Information
Input MUX Operation
There are two input signal paths – HP & Line. With the
prompt setting, G1420 allows the setting of different
gains for BTL and SE modes. Generally, speakers
typically require approximately a factor of 10 more
gain for similar volume listening levels as compared
with headphones.
SE Gain(HP) =
-3 dB
-(RF(HP)/RI(HP))
BTL Gain(LINE) =
fc
-2(RF(LINE)/RI(LINE))
To achieve headphones and speakers listening parity,
(RF(LINE/RI(LINE)) is suggested to be 5 times of (RF(HP)/
RI(HP)). The ratio of (RF(HP)/RI(HP)) can be determined by
the applications. When the optimum distortion performance into the headphones (clear sound) is important, gain of –1 ((RF(HP) / RI(HP)) = 1) is suggested.
Figure B
Bridged-Tied Load Mode Operation
G1420 has two linear amplifiers to drive both ends of
the speaker load in Bridged-Tied Load (BTL) mode
operation. Figure C shows the BTL configuration. The
differential driving to the speaker load means that
when one side is slewing up, the other side is slewing
down, and vice versa. This configuration in effect will
double the voltage swing on the load as compared to a
ground reference load. In BTL mode, the peak-to-peak
voltage VO(PP) on the load will be two times than a
ground reference configuration. The voltage on the
load is doubled, this will also yield 4 times output
power on the load at the same power supply rail and
loading. Another benefit of using differential driving
configuration is that BTL operation cancels the dc offsets, which eliminates the dc coupling capacitor that is
needed to cancelled dc offsets in the ground reference
configuration. Low-frequency performance is then limited only by the input network and speaker responses.
Cost and PCB space can be minimized by eliminating
the dc coupling capacitors.
Single Ended Mode Operation
G1420 can drive clean, low distortion SE output power
into headphone loads (generally 16Ω or 32Ω) as in
Figure A. Please refer to Electrical Characteristics to
see the performances. A coupling capacitor is needed
to block the dc offset voltage, allowing pure ac signals
into headphone loads. Choosing the coupling capacitor will also determine the 3 dB point of the high-pass
filter network, as Figure B.
fC=1/(2πRLCC)
For example, a 68uF capacitor with 32Ω headphone
load would attenuate low frequency performance below 73Hz. So the coupling capacitor should be well
chosen to achieve the excellent bass performance
when in SE mode operation.
VDD
VDD
Vo(PP)
Vo(PP)
CC
VDD
RL
RL
2xVo(PP)
Vo(PP)
-Vo(PP)
Figure A
Figure C
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G1420
Global Mixed-mode Technology Inc.
MUTE and SHUTDOWN Mode Operations
G1420 implements the mute and shutdown mode
operations to reduce supply current, IDD, to the absolute minimum level during nonuse periods for
battery-power conservation. When the shutdown
pin (pin 8) is pulled high, all linear amplifiers will be
deactivated to mute the amplifier outputs. And
G1420 enters an extra low current consumption
state, IDD is smaller than 5µA. If pulling mute-in pin
(pin 11) high, it will force the activated linear amplifier to supply the VDD/2 dc voltage on the output to
mute the AC performance. In mute mode operation,
the current consumption will be a little different between BTL, SE. (SE < BTL) Typically, the supply
current is about 2.5mA in BTL mute operation.
Shutdown and Mute-In pins should never be left
unconnected, this floating condition will cause the
amplifier operations unpredictable.
VDD
100 kΩ
50 kΩ
Bypass
100 kΩ
Figure D
Junction Temperature Measurement
Characterizing a PCB layout with respect to thermal
impedance is very difficult, as it is usually impossible to know the junction temperature of the IC.
G1420 TJ (pin 2) sources a current inversely proportional to the junction temperature. Typically TJ
sources–120µA for a 5V supply at 25°C. And the
slope is approximately 0.22µA/°C. As the resistors
have a tolerance of ±20%, these values should be
calibrated on each device. When the temperature
sensing function is not used, TJ pin can be left
floating or tied to VDD to reduce the current consumption.
Temperature sensing circuit is shown on Figure E.
Optimizing DEPOP Operation
Circuitry has been implemented in G1420 to minimize the amount of popping heard at power-up and
when coming out of shutdown mode. Popping occurs whenever a voltage step is applied to the
speaker and making the differential voltage generated at the two ends of the speaker. To avoid the
popping heard, the bypass capacitor should be
chosen promptly, 1/(CBx100kΩ) ≦ 1/(CI*(RI+RF)).
Where 100kΩ is the output impedance of the
mid-rail generator, CB is the mid-rail bypass capacitor, CI is the input coupling capacitor, RI is the
input impedance, RF is the gain setting impedance
which is on the feedback path. CB is the most important capacitor. Besides it is used to reduce the
popping, CB can also determine the rate at which
the amplifier starts up during startup or recovery
from shutdown mode.
VDD
R
De-popping circuitry of G1420 is shown on Figure D.
The PNP transistor limits the voltage drop across
the 50kΩ by slewing the internal node slowly when
power is applied. At start-up, the voltage at
BYPASS capacitor is 0. The PNP is ON to pull the
mid-point of the bias circuit down. So the capacitor
sees a lower effective voltage, and thus the charging is slower. This appears as a linear ramp (while
the PNP transistor is conducting), followed by the
expected exponential ramp of an R-C circuit.
R
5R
TJ
Figure E
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G1420
Global Mixed-mode Technology Inc.
Package Information
C
D
24
L
D1
E1 E
E2
1
Note 5
θ
A2
A
A1
e
b
TSSOP-24 (FD) Package
NOTE:
1. Package body sizes exclude mold flash protrusions or gate burrs
2. Tolerance ±0.1mm unless otherwise specified
3. Coplanarity : 0.1mm
4. Controlling dimension is millimeter. Converted inch dimensions are not necessarily exact.
5. Die pad exposure size is according to lead frame design.
6. Follow JEDEC MO-153
SYMBOLS
A
A1
A2
b
C
D
D1
E
E1
E2
e
L
θ
MIN
DIMENSION IN MM
NOM
----0.00
0.80
0.19
0.20
7.7
4.4
4.30
2.7
0.45
0º
--------1.00
--------7.8
----6.40 BSC
4.40
----0.65 BSC
0.60
-----
MAX
MIN
1.20
0.15
1.05
0.30
----7.9
4.9
----0.000
0.031
0.007
0.008
0.303
0.173
4.50
3.2
0.169
0.106
0.75
8º
0.018
0º
DIMENSION IN INCH
NOM
--------0.039
--------0.307
----0.252 BSC
0.173
----0.026 BSC
0.024
-----
MAX
0.047
0.006
0.041
0.012
----0.311
0.193
0.177
0.126
0.030
8º
Taping Specification
PACKAGE
Q’TY/REEL
TSSOP-24 (FD)
2,500 ea
Feed Direction
T ypical T S SO P Package O rientation
GMT Inc. does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and GMT Inc. reserves the right at any time without notice to change said circuitry and specifications.
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