EVALUATION
G
AVAILABLE
CHARGE PUMP DC-TO-DC VOLT AGE CONVERTER
KIT
TC7660
FEATURES
■ Converts +5V Logic Supply to ±5V System
■ Wide Input Voltage Range ....................1.5V to 10V
■ Efficient Voltage Conversion.........................99.9%
■ Excellent Power Efficiency ...............................98%
■ Low Power Supply...............................80µA @ 5V
■ Low Cost and Easy to Use
— Only Two External Capacitors Required
■ RS232 Negative Power Supply
■ Available in Small Outline (SO) Package
■ Improved ESD Protection ....................... Up to 3kV
■ No Dx Diode Required for High Voltage Operation
PIN CONFIGURATION (DIP and SOIC)
NC
CAP
ND
CAP
1
+
2
3
–
4
TC7660CPA
TC7660EPA
TC7660IJA
+
8
V
7
OSC
LOW
6
VOLTAGE (LV)
5
V
OUT
NC = NO INTERNAL CONNECTION
NC
CAP
GND
CAP
1
+
2
3
–
4
TC7660COA
TC7660CPA
+
8
V
OSC
7
LOW
6
VOLTAGE (LV)
V
5
OUT
GENERAL DESCRIPTION
The TC7660 is a pin-compatible replacement for the
Industry standard TC7660 charge pump voltage converter.
It converts a +1.5V to +10V input to a corresponding – 1.5V
to -10V output using only two low-cost capacitors, eliminating inductors and their associated cost, size and EMI.
IN
The on-board oscillator operates at a nominal frequency of 10kHz. Operation below 10kHz (for lower supply
current applications) is possible by connecting an external
capacitor from OSC to ground (with pin 1 open).
The TC7660 is available in both 8-pin DIP and 8-pin
SOIC packages in commercial and extended temperature
ranges.
ORDERING INFORMATION
Temperature
Part No. Package Range
TC7660COA 8-Pin SOIC 0°C to +70°C
TC7660CPA 8-Pin Plastic DIP 0°C to +70°C
TC7660EOA 8-Pin SOIC – 40°C to +85°C
TC7660EPA 8-Pin Plastic DIP – 40°C to +85°C
TC7660IJA 8-Pin CerDIP – 40°C to +85°C
TC7660MJA 8-Pin CerDIP – 55°C to +125°C
TC7660EV Evaluation Kit for
Charge Pump Family
FUNCTIONAL BLOCK DIAGRAM
V+CAP
82
OSC
LV
7
6
RC
OSCILLATOR
÷ 2
INTERNAL
VOLTAGE
REGULATOR
VOLTAGE–
LEVEL
TRANSLATOR
TC7660
3
© 2001 Microchip Technology Inc. DS21465A
GND
+
LOGIC
NETWORK
4
5
CAP
V
OUT
–
TC7660-7 9/30/96
TC7660
CHARGE PUMP DC-TO-DC
VOLTAGE CONVERTER
ABSOLUTE MAXIMUM RATINGS*
Operating Temperature Range
C Suffix ..................................................0°C to +70°C
Supply Voltage ...................................................... +10.5V
LV and OSC Inputs
Voltage (Note 1) ..........................– 0.3V to (V++0.3V)
for V+ < 5.5V
(V+ – 5.5V) to (V++0.3V)
for V+ > 5.5V
Current Into LV (Note 1).....................20 µA for V+ > 3.5V
Output Short Duration (V
≤ 5.5V) ........Continuous
SUPPLY
Power Dissipation (TA ≤ 70°C) (Note 2)
CerDIP............................................................800mW
Plastic DIP ......................................................730mW
SOIC...............................................................470mW
I Suffix...............................................– 25°C to +85°C
E Suffix ............................................. – 40°C to +85°C
M Suffix........................................... – 55°C to +125°C
Storage Temperature Range ................– 65°C to +150°C
Lead Temperature (Soldering, 10 sec) .................+300°C
*Static-sensitive device. Unused devices must be stored in conductive
material. Protect devices from static discharge and static fields. Stresses
above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only and functional
operation of the device at these or any other conditions above those
indicated in the operation sections of the specifications is not implied.
Exposure to absolute maximum rating conditions for extended periods
may affect device reliability.
ELECTRICAL CHARACTERISTICS: Specifications Measured Over Operating Temperature Range With,
V+ = 5V, C
Symbol Parameter Test Conditions Min Typ Max Unit
+
I
+
V
H
+
V
L
R
OUT
F
OSC
P
EFF
V
OUT EFF
Z
OSC
NOTES: 1. Connecting any input terminal to voltages greater than V+ or less than GND may cause destructive latch-up. It is recommended that no
Supply Current RL = ∞ — 80 180 µA
Supply Voltage Range, High Min ≤ TA ≤ Max, 3 — 10 V
RL = 10 kΩ, LV Open
Supply Voltage Range, Low Min ≤ TA ≤ Max, 1.5 — 3.5 V
RL = 10 kΩ, LV to GND
Output Source Resistance I
= 20mA, TA = 25°C — 70 100 Ω
OUT
I
= 20mA, 0°C ≤ TA ≤ +70°C — — 120 Ω
OUT
(C Device)
I
= 20mA, – 40°C ≤ TA ≤ +85°C — — 130 Ω
OUT
(I Device)
= 20mA, –55°C ≤ TA ≤ +125°C — 104 150 Ω
I
OUT
(M Device)
+
V
= 2V, I
0°C ≤ TA ≤ +70°C
+
V
= 2V, I
– 55°C ≤ TA ≤ +125°C (Note 3)
Oscillator Frequency Pin 7 open — 10 — kHz
Power Efficiency RL = 5kΩ 95 98 — %
Voltage Conversion Efficiency RL = ∞ 97 99.9 — %
Oscillator Impedance V+ = 2V — 1 — MΩ
V+ = 5V — 100 — kΩ
inputs from sources operating from external supplies be applied prior to "power up" of the TC7660.
2. Derate linearly above 50°C by 5.5 mW/°C.
3. TC7660M only.
4. The TC7660 can be operated without the Dx diode over full temperature and voltage range.
= 0, Test Circuit (Figure 1), unless otherwise indicated.
OSC
= 3 mA, LV to GND — 150 300 Ω
OUT
= 3 mA, LV to GND — 160 600 Ω
OUT
TC7660-7 9/30/96
2
© 2001 Microchip Technology Inc. DS21465A
CHARGE PUMP DC-TO-DC
VOLTAGE CONVERTER
TYPICAL PERFORMANCE CHARACTERISTICS (Circuit of Figure 1)
TC7660
Operating Voltage vs. Temperature
12
10
8
6
SUPPLY VOLTAGE RANGE
4
SUPPLY VOLTAGE (V)
2
0
–25 0 +25 +75 +100 +125
–55
TEMPERATURE (°C)
+50
Output Source Resistance vs. Supply Voltage
10k
1k
TA = +25°C
Power Conversion Eff. vs. Osc. Freq.
100
98
I
= 1 mA
OUT
96
94
92
I
= 15 mA
OUT
90
88
86
84
TA = +25°C
82
V+ = +5V
POWER CONVERSION EFFICIENCY (%)
80
100 1k 10k
OSCILLATOR FREQUENCY (Hz)
Output Source Resistance vs. Temperature
500
I
= 1 mA
OUT
450
400
200
150
100Ω
OUTPUT SOURCE RESISTANCE (Ω)
10Ω
SUPPLY VOLTAGE (V)
Freq. of Osc. vs. Ext. Osc. Capacitance
10k
1k
100
OSCILLATOR FREQUENCY (Hz)
10
1
© 2001 Microchip Technology Inc. DS21465A TC7660-7 9/30/96
10 100 1000 10k
OSCILLATOR CAPACITANCE (pF)
78
6543210
TA = +25°C
V+ = +5V
Unloaded Osc. Freq. vs. Temperature
OSCILLATOR FREQUENCY (kHz)
3
V+ = +2V
100
V + = +5V
50
OUTPUT SOURCE RESISTANCE (Ω)
0
–55 –25 0 +25 +50 +75 +100 +125
20
V+ = +5V
18
16
14
12
10
8
6
–55
TEMPERATURE (°C)
–25 0 +25 +50 +75 +100 +125
TEMPERATURE (°C)
TC7660
TYPICAL CHARACTERISTICS (Cont.)
CHARGE PUMP DC-TO-DC
VOLTAGE CONVERTER
Output Voltage vs. Output Current
0
–1
–2
–3
–4
–5
–6
–7
OUTPUT VOLTAGE (V)
–8
–9
–10
10 20 30 40 50 60 70 80 90 100
0
OUTPUT CURRENT (mA)
TA = +25°C
LV OPEN
Supply Current and Power Conversion Efficiency vs. Load Current
100
90
80
70
60
50
40
30
20
10
POWER CONVERSION EFFICIENCY (%)
0
1.5 3.0 4.5 6.0 7.5 9.0
LOAD CURRENT (mA)
TA = +25°C
V+ = 2V
20
18
16
14
12
10
8
6
4
SUPPLY CURRENT (mA) (Note)
2
0
Output Voltage vs. Load Current
5
TA = +25°C
4
V+ = +5V
3
2
1
0
–1
–2
OUTPUT VOLTAGE (V)
–3
–4
–5
0
10 20 30 40 50 60 70 80
100
90
80
70
60
50
40
30
20
10
POWER CONVERSION EFFICIENCY (%)
0
10 20 30 40 50 60
SLOPE 55Ω
LOAD CURRENT (mA)
TA = +25°C
V+ = +5V
LOAD CURRENT (mA)
100
90
80
70
60
50
40
30
20
SUPPLY CURRENT (mA) (Note)
10
0
2
1
0
–1
OUTPUT VOLTAGE (V)
–2
0
TC7660-7 9/30/96
Output Voltage vs. Load Current
TA = +25°C
V+ = +2V
SLOPE 150Ω
123 4567 8
LOAD CURRENT (mA)
4
© 2001 Microchip Technology Inc. DS21465A
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