2
PFM Step-Up DC/DC Regulators
TC125
TC126
TC125/6-1 8/3/99
2001 Microchip Technology Inc
DS21372A
ABSOLUTE MAXIMUM RATINGS*
Voltage on VDD, SENSE/VDD, LX, SHDN pins . –0.3 to +12V
LX Sink Current .................................................... 400 mA
Power Dissipation ............................................... 150 mW
Operating Temperature ............................ –40
°C to +85°C
Storage Temperature (TSTG) .................. –40°C to +125°C
ELECTRICAL CHARACTERISTICS:
VIN = VOUT x 0.6, TA = 25°C, SHDN = VOUT (TC125), unless otherwise noted.
Symbol
Parameter
Test Conditions
Min
Typ
Max
Unit
VOUT
Output Voltage
VR - 2.5% VR ± 0.5% VR + 2.5%
V
VDD
Operating Voltage Range
Note 4
0.70
—
10.0
V
VSTART
Start-Up Voltage
IOUT = 1 mA
—
0.80
0.90
V
IDD
Operating Supply Current
Note 2
TC125
VOUT = 2V,
—
14
28
A
IOUT = 10 mA
TC125/126
VOUT = 3V,
—
20
40
IOUT = 30 mA
TC125/126
VOUT = 5V,
—
32
64
IOUT = 50 mA
INL
No Load Supply Current
IOUT = 0
VOUT = 2V
—
5
9
A
VOUT = 3V
—
5
10
VOUT = 5V
6
11
ISTBY
Standby Supply Current
VIN= VOUT + 0.5V
VIN = 2V
—
2
4
A
VIN = 3V
—
3
5
VIN = 5V
—
3
5
ISHDN
Shutdown Supply Current
Note 2, SHDN = VIL
–
—
0.5
A
RLX(ON)
LX Pin ON Resistance
Note 2, Note 3,
VOUT = 2V
—
10
14
VLX = 0.4V
VOUT = 3V
—
6
8
VOUT = 5V
—
3
5
ILX
LX Pin Leakage Current
No External Components,
—
1
A
VOUT = VLX = 10V
DCYCLE
Duty Cycle
Note 2, Measured at LX Pin
70
75
80
%
fMAX
Maximum Oscillator Frequency
Note 2
85
100
115
KHz
VLXLIM
LX Pin Limit Voltage
Note 2
0.7
—
1.1
V
η
Efficiency
VOUT = 2V
—
70
—
%
VOUT = 3V
—
80
—
VOUT = 5V
—
85
—
VIH
SHDN Input Logic HIGH
0.75
—
V
VIL
SHDN Input Logic LOW
—
0.20
V
IINH
SHDN Input Current (High)
—
0.25
A
IINL
SHDN Pin Input Current (Low)
–0.25
—
A
NOTES: 1. VR is the factory output voltage setting.
2. VIN = VOUT x 0.95.
3. VDD input tied to SENSE input for TC126, as shown in Figure 2.
4. The VDD input of the TC126 must be operated between 2.2V and 10.0V for spec compliance.
The VPS input of the TC125 must be operated between 2.0V and 10.0V for spec compliance.
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.
*Static-sensitive device. Unused devices must be stored in conductive
material. Protect devices from static discharge and static fields. Stresses