M
High Current Charge Pump DC-to-DC Converter
TC962
Features
• Pin Compatible With TC7662/ICL7662/SI7661
• High Output Current 80mA
• No External Diodes Required
• Wide Operating Range 3V to 18V
• Low Output Impedance 28Ω Typ.
• No Low Voltage Terminal Required
• Application Zener On-Chip
• OSC Frequency Doubling Pin Option for Smaller
Output Capacitors
Applications
• Laptop Computers
• Disk Drives
• Process Instrumentation
• µP-Based Controllers
Device Selection Table
Part
Number
TC962COE 16-Pin SOIC Wide 0°C to +70°C
TC962CPA 8-Pin Plastic DIP 0°C to +70°C
TC962EPA 8-Pin Plastic DIP -40°C to +85°C
TC962IJA 8-Pin CERDIP -25°C to +85°C
TC962MJA 8-Pin CERDIP -55°C to +125°C
Package
Operating
Temp.
Range
General Description
The TC962 is an advanced version of the industry
standard TC7662 high voltage DC-to-DC converter.
Using improved design techniques and CMOS
construction, the TC962 can source as much as 80mA
versus the 7662’s 20mA capability.
As an inverter, the TC962 can put out voltages as high
as 18V and as low as 3V without the need for external
diodes. The output impedance of the device is a low
28Ω (with the proper capacitors), voltage conversion
efficiency is 99.9%, and power conversion efficiency is
97%.
The low voltage terminal (pin 6) required in some
TC7662 applications has been eliminated. Grounding
this terminal will double the oscillator frequency from
12kHz to 24kHz. This will allow the use of smaller
capacitors for the same output current and ripple, in
most applications. Only two external capacitors are
required for inverter applications. In the event an
external clock is needed to drive the TC962 (such as
paralleling), driving this pin directly will cause the
internal oscillator to sync to the external clock.
Pin 1, which is used as a test pin on the 7662, is a
voltage reference zener on the TC962. This zener
(6.4V at 5mA) has a dynamic impedance of 12Ω and is
intended for use where the TC962 is supplying current
to external regulator circu itry and a reference is neede d
for the regulator circuit. (See Section 3.0 Applications
Information).
The TC962 is compatible with the LTC1044, SI7661
and ICL7662. It should be used in designs that require
greater power and/or less input to output voltage drop.
It offers superior performance over the ICL7660S.
Package Type
16-Pin SOIC Wide
Zener
NC
C
NC
GND
NC
C
NC
1
2
+
3
4
TC962COE
5
6
–
7
8
8-Pin DIP
8-Pin CERDIP
Zener
1
+
C
–
C
•
TC962CPA
2
TC962EPA
3
TC962IJA
4
TC962MJA
Cathode
GND
2002 Microchip Technology Inc. DS21484B-page 1
V
8
C
7
6
FREQ x 2
V
5
DD
OSC
OUT
Cathode
16
15
14
13
12
11
10
9
V
DD
NC
C
OSC
NC
FREQ x 2
NC
V
OUT
NC
TC962
Functional Block Diagram
FREQ x 2
OSC/C
Timing
Zener
Cathode
6
–
7
II
+
–
Comparator
with Hysteresis
1
6.4V
8
V
DD
TC962
Level
Q
F/F
C
Q
V
REF
Shift
Level
Shift
Level
Shift
P SW1
N SW4
N SW2
2
+
+
CAP
C
P
External
OUT
GND
3
+
C
R
EXT
Level
Shift
N SW3
4
CAP
–
5
V
OUT
R
L
DS21484B-page 2 2002 Microchip Technology Inc.
TC962
1.0 ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings*
Supply Voltage (VDD to GND)..............................+18V
Input Voltage Any Pin
......................... (V
Current Into Any Pin............................................10mA
ESD Protection ................................................±2000V
Output Short Circuit ........... Continuous (at 5.5V Input)
Package Power Dissipation (T
SOIC.......................................................760 mW
PDIP........................................................730 mW
CERDIP ..................................................800 mW
Package Thermal Resistance
CERDIP, Rθ
PDIP, Rθ
J-A
............................................140°C/W
J-A
Operating Temperature Range
CPA, COE .......................................0°C to +70°C
IJA................................................-25°C to +85°C
EPA ..............................................-40°C to +85°C
MJA............................................-55°C to +125°C
Storage Temperature Range .............-65°C to +150°C
+0.3) to (VSS -0.3) (Note 1)
DD
≤ 70°C)
A
.........................................90°C/W
*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.
TC962 ELECTRICAL SPECIFICATIONS
Electrical Characteristics: VDD = 15V, TA = 25°C (See Figure 3-1) unless otherwise noted.
Symbol Parameter Min Typ Max Units Test Conditions
V
DD
I
S
R
O
F
OSC
P
EFF
V
DEF
V
Z
Z
ZT
Note 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 Voltage 3 — 18 V
Supply Current
V
= 15V
DD
= 5V
V
DD
Output Source
Resistance
Oscillator Frequency —
Power Efficiency 93
Voltage Efficiency 99
Zener Voltage 6.0 6.2 6.4 V IZ = 5mA
Zener Impedance — 12 — Ω IL = 2.5mA to 7.5mA
inputs from sources operating from external supplies be applied prior to "power up" of the TC962.
—
—
—
—
—
—
—
—
—
—
—
—
—
96
—
510
560
650
190
210
210
32
35
—
12
24
97
—
99.9
—
—
—
700
—
—
—
—
—
37
40
50
—
—
—
—
—
—
—
µAR
Ω I
kHz Pin 6 Open
%RL = 2kΩ
%RL = ∞
= ∞
L
TA = +25°C
≤ T
≤ +70°C
0
A
≤ T
-55°C
T
= +25°C
A
≤ T
≤ +70°C
0
A
≤ T
-55°C
= 20mA, VDD = 15V
L
= 80mA, VDD = 15V
I
L
= 3mA, VDD = 5V
I
L
Pin 6 GND
Over temperature range
A
A
≤ +125°C
≤ +125°C
2002 Microchip Technology Inc. DS21484B-page 3
TC962
2.0 PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 2-1.
TABLE 2-1: PIN FUNCTION TABLE
Pin No.
(8-Pin DIP)
(8-Pin CERDIP)
1 Zener Cathode Cathode of internal zener diode.
2C
3 GND Ground terminal.
4C
5V
6 FREQ x 2 If grounded, frequency doubles.
7C
8V
Symbol Description
+
-
OUT
OSC
DD
Positive side of external CP capacitor (pump cap).
Negative side of external CP capacitor (pump cap).
Output voltage.
Capacitor to GND will decrease frequency.
Input voltage.
Pin No.
(16-Pin SOIC)
1 Zener Cathode Cathode of internal zener diode.
2 NC No connect.
3C
4 NC No connect.
5 GND Ground terminal.
6 NC No connect.
7C
8 NC No connect.
9 NC No connect.
10 V
11 NC No connec t.
12 FREQ x 2 If grounded, frequency doubles.
13 NC No connect.
14 C
15 NC No connect.
16 V
Symbol Description
+
-
OUT
OSC
DD
Positive side of external CP capacitor (pump cap).
Negative side of external CP capacitor (pump cap).
Output voltage.
Capacitor to GND will decrease frequency.
Input voltage.
DS21484B-page 4 2002 Microchip Technology Inc.
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