
TC1240A
2
TC1240A-1 11/03/00
Positive Unregulated Doubling Charge Pump
with Shutdown in a SOT-23 Package
ABSOLUTE MAXIMUM RATINGS*
Input Voltage (VIN to GND) .......................... +5.8V, –0.3V
Output Voltage (OUT to GND) ............ +11.6V, VIN – 0.3V
Current at OUT Pin ................................................. 50 mA
Short-Circuit Duration –OUT to GND ................ Indefinite
Operating Temperature Range ...............–40
°C to +85°C
Thermal Resistance ............................................210
°C/W
Power Dissipation (TA = +25°C)............................600 mW
Storage Temperature (Unbiased) ..........–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 perma-
nent 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 operational sections of the specifications is not implied.
Exposure to Absolute Maximum Rating Conditions for extended periods
may affect device reliability.
ELECTRICAL CHARACTERISTICS: TA = –40°C to +85°C, VIN = +5.0V, C1 = C2 = 3.3F , SHDN = GND,
unless otherwise specified. Typical values are at TA = +25°C.
Symbol
Parameter
Test Conditions
Min
Typ
Max
Units
IDD
Supply Current
RLOAD = ∞
—
550
900
A
ISHDN
Shutdown Supply Current
SHDN = VIN
—
0.01
1.0
A
VMIN
Minimum Supply Voltage
2.5
—
V
VMAX
Maximum Supply Voltage
—
5.5
V
ILOAD
Output Current
20
—
mA
RSW
Sum of the RDS(ON) of the Four
ILOAD = 20mA
—
4
8
Internal MOSFET Switches
FOSC
Oscillator Frequency
TA = –40 °C to +85°C
—
160
—
kHz
FSW
Switching Frequency
TA = –40 °C to +85°C
40
80
125
kHz
VIH
Shutdown Input Logic High
VIN = VMIN to VMAX
1.4
—
V
VIL
Shutdown Input Logic Low
VIN = VMIN to VMAX
—
0.4
V
PEFF
Power Efficiency
ILOAD = 5mA
86
94
—
%
VEFF
Voltage Conversion
RLOAD = ∞
99
99.96
—
%
Efficiency
ROUT
Output Resistance
ILOAD = 20mA
—
12
—
(Note 1)
TA = –40°C to +85°C—
—
25
NOTE: 1. Capacitor Contribution is approximately 26% of the output impedance [ESR = 1 / pump frequency x capacitance)].
2. Switching frequency is one-half internal oscillator frequency.
PIN DESCRIPTION
Pin No.
(6-Pin SOT-23A)
Symbol
Description
1
VIN
Power Supply Input.
2
GND
Ground.
3
C –
Commutation Capacitor Negative Terminal.
4
SHDN
Shutdown Input (Active High).
5
OUT
Doubled Output Voltage.
6
C+
Commutation Capacitor Positive Terminal.