TC18C43 Datasheet, PDF (3/7 Pages) TelCom Semiconductor, Inc – BiCMOS CURRENT MODE PWM CONTROLLERS

BiCMOS CURRENT MODE
PWM CONTROLLERS
1
TC18C43
TC28C43
TC38C43
ELECTRICAL CHARACTERISTICS (Cont): unless otherwise stated, these specifications apply over specified
temperature range. V_IN = V_DD = 15V; R_T = 71 kΩ; C_T = 150 pF.
2
TC18C4X
TC28C4X
TC38C4X
Parameter
Test Conditions
Min Typ Max Min Typ Max Units
Output Section
R_{DS (ON)}
R_{DS (ON)}
Rise Time
Fall Time
Cross Conduction
I_SINK = 20mA
I_SOURCE = 20mA
C_L = 1nF (Note 1)
C_L = 1nF (Note 1)
In Coulombs (Note 1)
V_DD Ma
Note 1
Undervoltage Lockout Section
Start Threshold
x8C43
Undervoltage Threshold x8C43
PWM Section
Maximum Duty Cycle
x8C43 (Note 1)
Minimum Duty Cycle
Supply Current
Start Up
Operating
T_A = 25°C, V_IN < V_UV; Figure 1
V_FB = V(I_SENSE) = 0V; Figure 4
—
7
15
—
7
15
Ω
—
11
20
—
40
60
—
11
—
35
15
Ω
60 nsec
3
—
30
60
—
30
40 nsec
— 6.5 —
— 6.5
—
nC
—
—
18
—
—
18
V
7.9 8.4 8.8
7.9 8.4
8.8
V
7.2 7.6 7.9
7.2 7.6
7.9
V
4
95
97 100
95
97
100
%
0
0
%
50 170 300
50 170 300
µA
1
2
1
1.5 mA
NOTES: 1. These parameters, although guaranteed over the
recommended operating conditions, are not tested in
production.
2. Parameter measured at trip point of latch.
3. Gain ratio is defined as:
∆VCOMP
∆V(ISENSE)
where 0 ≤ V(I_SENSE) ≤ 0.8V
4. Output frequency equals oscillator frequency for the
x8C43.
5. PSRR of V_REF, Error Amp and PWM Comparator
combination.
5
TelCom Semiconductor reserves the right to make changes in the circuitry or specifications detailed in this manual at any time without notice. Minimums
and maximums are guaranteed. All other specifications are intended as guidelines only. TelCom Semiconductor assumes no responsibility for the use of
any circuits described herein and makes no representations that they are free from patent infringement.
*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 operational sections of the specifications is not implied. Exposure to Absolute
Maximum Rating Conditions for extended periods may affect device reliability.
6
PIN DESCRIPTION
Pin No.
8-Pin
1
2
3
Pin No
14-Pin
2
4
1
3
5
Pin No
16-Pin
1
2
3
4
5
4
7
6
Symbol
NC
NC
CMPTR
V_FB
I_SENSE
R_T/C_T
Description
No Connection
No Connection
Compensation of the feedback loop response.
Feedback of voltage to error amplifier to regulate voltage.
For sensing pass transistor current and terminate drive when current
limit threshold is reached at this pin.
Capacitor and resistor input to set oscillator frequency of this PWM
controller. The resistor is connected from V_REF output to R_T/C_T.
The capacitor is connected from R_T/C_T to ANALOG GND.
7
8
TELCOM SEMICONDUCTOR, INC.
4-95