GMT G5931

G5931
Global Mixed-mode Technology Inc.
Switched-Capacitor Voltage Inverters with Shutdown
Features
„
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General Description
Inverts Input Supply Voltage
25mA Output Current with A Voltage Drop of
250mV
0.45mA Quiescent Current at 3.3V Supply
99% Voltage Conversion Efficiency
1.8V to 5V operating range
Require Only Two Capacitors
Over-Temperature Protected
2KV ESD Rating
8-Pin SOP Package
The G5931 is an unregulated charge-pump voltage
inverter which may be used to generate a negative
supply from positive input. Input voltages ranging from
+1.8V to +5V can be inverted into a -1.8V to -5V output supply. The devices is ideal for both battery- powered and board level voltage conversion applications
with a typical operating current of 0.45mA at 3.3V
supply.
The G5931 can deliver 25mA output current with a
voltage drop of 250mV. The parts are over -temperature
protected.
Applications
„
Cell Phone
Small LCD Panels
„ Portable Equipment
„ Handy-Terminals, PDAs
„ Battery-Operated Equipment
Applications include cell phones, PDAs, and other
portable equipment. The devices is available in 8-pin
SOP Package.
„
Ordering Information
ORDER
NUMBER
MARKING
TEMP.
RANGE
PACKAGE
(Pb free)
G5931P1U
G5931
-40°C to 85°C
SOP-8
Note: P1 : SOP-8
U: Tape & Reel
Pin Configuration
Typical Operating Circuit
G5931
1
NC
1
8
IN
CP+
2
7
NC
GND
3
6
NC
CP-
4
5
OUT
2
C1
3
4
8
NC
IN
CP+
NC
7
GND
NC
6
CP-
OUT
VIN (1.8V to 5V)
C3
5
C2
SOP-8
C1,C2,C3: 1µF MLCC (X5R)
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.2 Preliminary
Jun 22, 2005
1
G5931
Global Mixed-mode Technology Inc.
Absolute Maximum Ratings
Storage Temperature……………………-65°C to 150°C
Junction Temperature…………………………..…150°C
Reflow Temperature (Soldering, 10sec)…..……260°C
Thermal Resistance
SOIC (θJA)………………………………..…….160°C/W
ESD Rating HBM……………………….…………2000V
IN to GND Voltage Range………….…….-0.3V to +5.5V
OUT to GND Voltage Range..............…-5.5V to +0.3V
C1+ to GND Voltage Range……..…-0.3V to (VIN+0.3V)
C1- to GND Voltage Range…..….(VOUT -0.3V) to +0.3V
OUT Output Current………………………………100mA
Operating Temperature Range….………-40°C to 85°C
OUT Short Circuit to GND..........………………Indifinite
Note: Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin.
Electrical Characteristics
(VIN=+3.3V, C1 = C2 = C3= 1µF, TA= -40 to 85°C unless otherwise noted. Typical values is at TA=25°C.)
PARAMETER
Input Voltage, VIN
CONDITION
RLOAD=10kΩ
o
Supply Current, IQ
TA=25 C
Charge Pump Frequency, FSW
Output Resistance(Note)
VIN=5V
ILOAD=5mA
MIN
TYP
MAX
UNIT
1.8
---
5
V
---
0.45
0.5
mA
255
---
295
8.3
330
9.6
KHz
Ω
ILOAD=5mA
---
14
---
mV p-p
Voltage Conversion Efficiency
ILOAD=25mA
No Load
--99
56
---
-----
mV p-p
%
Power Efficiency
ILOAD=5mA
---
93
---
%
Output Ripple
Electrical Characteristics
(VIN=+5V, C1 = C2 = C3= 1µF, TA= -40 to 85°C unless otherwise noted. Typical values is at TA=25°C.)
MIN
TYP
MAX
Input Voltage, VIN
Supply Current, IQ
PARAMETER
RLOAD=10kΩ
1.8
---
5
V
TA=25oC
---
0.92
---
mA
Charge Pump Frequency, FSW
Output Resistance(Note)
VIN=5V
ILOAD=5mA
ILOAD=5mA
ILOAD=25mA
No Load
--------99
290
8.8
25
100
---
-----------
KHz
Ω
mV p-p
mV p-p
%
90
---
%
Output Ripple
Voltage Conversion Efficiency
CONDITION
Power Efficiency
ILOAD=10mA
--Note: Capacitor contribution (ESR component plus (1/FSW)・C) is approximately 20% of output.
UNIT
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.2 Preliminary
Jun 22, 2005
2
G5931
Global Mixed-mode Technology Inc.
Typical Performance Characteristics
(VIN=3.3V, C1=C2=C3=1µF, TA=25°C, unless otherwise noted.)
Output Voltage vs. Current
VIN=2.0V
VIN=1.8V
-1.5
-2
Output Voltage (V)
Output Voltage (V)
-1
VIN=2.5V
-3
VIN=3.3V
-4
Output Voltage vs. Temperature
-1
0
VIN=3.6V
-5
VOUT=-3.3V
IOUT=0mA
-2
-2.5
-3
-3.5
VIN=5.0V
-6
0
5
10 15 20 25
-4
-40
30 35 40 45 50 55 60
-20
0
Output Current (mA)
10
20
40
60
80
100
Temperature (°C)
Output Resistance vs. Input Voltage
10
Output Resistance vs. Temperature
9
9.5
Output Resistance (Ω)
Output Resistance (Ω)
8
7
6
5
4
3
2
VIN=2.0V
9
8.5
VIN=1.8V
8
7.5
VIN=3.3V
1
0
1.8
2.2
2.6
3
3.4
3.8
4.2
4.6
7
-40
5
-20
0
Input Voltage (V)
300
300
250
250
Frequency (kHz)
Frequency (kHz)
350
200
150
50
50
0
-40
0
3
3.4
3.8
4.2
4.6
100
150
100
2.6
80
200
100
2.2
60
Frequency vs. Temperature
Frequency vs. Input Voltage
350
1.8
20
40
Temperature (°C)
5
-20
0
20
40
60
80
100
Temperature (°C)
Input Voltage (V)
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.2 Preliminary
Jun 22, 2005
3
G5931
Global Mixed-mode Technology Inc.
Typical Performance Characteristics (continued)
Supply Current vs. Input Voltage
0.5
1
0.45
0.9
0.4
0.8
0.7
Supply Current (mA)
Supply Current (mA)
Supply Current vs. Temperature
0.6
0.5
0.4
0.3
0.35
0.3
0.25
0.2
0.15
0.2
0.1
0.1
0.05
0
-40
0
1.8
2.2
2.6
3
3.4
3.8
Input Voltage (V)
4.2
4.6
5
-20
0
20
40
60
80
100
Temperature ( ° C)
Output Ripple Waveform
Efficiency vs. Output Current
100
95
90
Efficiency (%)
85
VIN=1.8V
80
VIN=3.6V
VIN=2.5V
75
VIN=2.0V
70
VIN=5.0V
VIN=3.3V
65
60
55
50
0
5
10 15 20 25 30 35 40 45 50 55 60
Output Current (mA)
Recommended Minimum Footprint
SOP-8
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.2 Preliminary
Jun 22, 2005
4
G5931
Global Mixed-mode Technology Inc.
Pin Descriptions
PIN
NAME
1,6,7
2
NC
C1+
Not Internally Connected
Flying Capacitor’s Positive Terminal
FUNCTION
3
4
GND
C1-
Ground
Flying Capacitor’s Negative Terminal
5
8
OUT
IN
Inverting Charge-Pump Output
Power-Supply Positive Voltage Input
Detailed Description
The G5931 contains four large switches which are
switched in a sequence to inverter the input supply
voltage. Energy transfer and storage are provided by
external capacitors. Fig. 1 illustrates the voltage conversion scheme. When S1 and S3 are closed, C1
charges to the supply voltage VIN. During this time interval, switches S2 and S4 are open. In the second
time interval, S1 and S3 are open; at the same time,
S2 and S4 are closed, C1 is charging C2. After a
number of cycles, the voltage across C2 will be
pumped to VIN. Since the anode of C2 is connected to
ground, the output at the cathode of C2 equals -(VIN)
when there are no load current.
ON resistance of the internal MOSFET switches, the
oscillator frequency, the capacitance and the ESR of
both C1 and C2. Since the switching current charging
and discharging C1 is approximately twice as the output current, the effect of the ESR of the pumping capacitor C1 will be multiplied by four in the output resistance. The output capacitor C2 is charging and discharging at a current approximately equal to the output
current, therefore, this ESR term only counts once in
the output resistance. A good approximation of Rout is:
ROUT ≅ 2RSW +
The main application of G5931 is to generate a negative supply voltage. The range of the input supply voltage is 1.8V to 5V. The output characteristics of this
circuit can be approximated by an ideal voltage source
in series with a resistance. The voltage source equals
-(VIN). The output resistance, Rout, is a function of the
2
+ 4ESRC1 + ESRC2
fOSCxC1
Where RSW is the sum of the ON resistance of the internal MOSFET switches shown in Figure 1.
High capacitance, low ESR capacitors will reduce the
output resistance.
S1
S2
IN
C1
C2
S3
S4
VOUT=-(VIN)
Figure 1. Ideal Voltage Inverter
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.2 Preliminary
Jun 22, 2005
5
G5931
Global Mixed-mode Technology Inc.
Application Information
The output resistance is dependent on the capacitance and ESR values of the external capacitors. The
output voltage drop is the load current times the output
resistance, and the power efficiency is
Table 1. Low-ESR Capacitor Manufacturers
PRODUCTION
METHOD
MANUFACTURER
SERIES
Surface-Mount
Ceramic
AVX
Matsuo
X7R
X7R
2
η=
Capacitor Selection
To maintain the lowest output resistance, use capacitors with low ESR (Table 1). The charge-pump output
resistance is a function of C1’s and C2’s ESR. Therefore, minimizing the charge-pump capacitor’s ESR
minimizes the total output resistance.
Where IQ(VIN) is the quiescent power loss of the IC
device,and IL2Rout is the conversion loss associated
with the switch on-resistance, the two external capacitors and their ESRs.
Flying Capacitor (C1)
Increasing the flying capacitor’s value reduces the
output resistance. Above a certain point, increasing
C1’s capacitance has a negligible effect because the
output resistance becomes dominated by the internal
switch resistance and capacitor ESR.
Input Bypass Capacitor (C3)
Bypass the incoming supply to reduce its AC impedance and the impact of the G5931’s switching noise. A
bypass capacitor with a value equal to that of C1 is
recommended.
Voltage Inverter
The most common application for these devices is a
charge-pump voltage inverter (Figure 2). This application requires only two external components— capacitors C1 and C2—plus a bypass capacitor, if necessary.
Output Capacitor (C2)
Increasing the output capacitor’s value reduces the
output ripple voltage. Decreasing its ESR reduces
both output resistance and ripple. Lower capacitance
values can be used with light loads if higher output
ripple can be tolerated. Use the following equation to
calculate the peak-to-peak ripple:
VRIPPLE =
IL
f OSC xC2
IL R L
POUT
= 2
2
PIN
IL R L + IL R OUT + I Q ( VIN )
Layout and Grounding
Good layout is important, primarily for good noise performance. To ensure good layout, mount all components as close together as possible, keep traces short
to minimize parasitic inductance and capacitance, and
use a ground plane.
+ 2xIL + ESR C2
C1
1µF
8
C3
1µF
1
6
7
2 +
C1+
4
C1-
IN
NC
NC
NC
OUT
G5931
5
RL
NEGATIVE
OUTPUT
-1 x VIN
25mA
C2
+ 1µF
GND
3
Figure 2. Typical Application Circuit
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.2 Preliminary
Jun 22, 2005
6
G5931
Global Mixed-mode Technology Inc.
Package Information
0.008TYP
E
H
L
D
θ
0.015x45º
A2
0.004MAX.
e
A
SEATING PLANE
A1
B
SOP-8 Package
Note:
1. JEDEC Outline: MS-012 AA/E.P. Version: N/A
2. Dimension “D” does not include mold flash, protrusions or gate burrs. Mold flash, protrusions and gate burrs
shall not exceed .15mm (.006in) per side.
3. Dimensions “E” does not include inter-lead flash, or protrusions inter-lead flash and protrusions shall not exceed .25mm (.010in) per side.
SYMBOL
MIN.
A
A1
A2
B
D
E
4.80
3.81
e
H
L
θ
DIMENSION IN MM
MAX.
1.35
0.00
-----
DIMENSION IN INCH
MIN.
MAX.
1.75
0.13
1.50
0.053
0.000
-----
4.98
3.99
0.189
0.150
5.80
6.20
0.228
0.244
0.41
1.27
0.016
0.050
0º
8º
0º
8º
0.41TYP
0.069
0.005
0.059
0.016TYP
1.27TYP
0.196
0.157
0.05TYP
Taping Specification
PACKAGE
Q’TY/REEL
SOP-8
2,500 ea
Feed Direction
Typical SOP Package Orientation
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.
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 0.2 Preliminary
Jun 22, 2005
7