TC170 Datasheet, PDF (3/8 Pages) TelCom Semiconductor, Inc – CMOS CURRENT MODE PWM CONTROLLER

CMOS CURRENT MODE
PWM CONTROLLER
1
TC170
ELECTRICAL CHARACTERISTICS (Cont.): V_IN = 16V, R_O = 24kΩ, C_O = 1nF, T_A = 25°C, unless otherwise indicated.
Symbol Parameter
Test Conditions
Min
Typ Max
2 ^Unit
Output Stage (Cont.)
V_OH
Output High Level
V_OL
Output High Level
t_R
Output Rise Time
t_F
Output Fall Time
Undervoltage Lockout
Start-Up
Threshold Hysteresis
Supply
I_SOURCE = 20mA
I_SOURCE = 100mA
C_L = 1000pF
C_L = 1000pF
Threshold
V_DD – 1V
V_DD – 4V
50
50
7.15
7.7
0.5
0.75
150
150
8.25
1
V
V
nsec
nsec
3 ^V
V
I_S Standby Supply Current
2.7
3.8
mA
PIN DESCRIPTION
Pin No.
(16-Pin PDIP)
Symbol
Description
1
SOFT START/I_LIM Soft Start Adjust / Current Limit. For setting the peak current threshold of sense inputs (pins
3 and 4). Second function of this pin is Soft-Start Adjust.
2
V_REF OUT
Reference supply output of 5.1 volts. It can supply a minimum of 10mA.
3
– I_SENSE IN
– Current Sense Input. Inverting input for sensing peak current of the pass transistor
through series sense current monitor resistor.
4
+ I_SENSE IN
+ Current Sense Input. Non-inverting input used in conjunction with pin 3. This senses the
positive end of current monitor resistor.
5
+ ERROR AMP IN + Error Amp In. Non-inverting input for output voltage regulation.
6
– ERROR AMP IN – Error Amp In. Inverting input of the amplifier for the reference voltage.
7
CMPTR
For compensation of the feedback loop response.
8
C_O
Timing capacitor (C_O) input to set oscillator frequency in conjunction with pin 9, R_O, resistor
input. Second function is for setting crossover dead time of pin 11and 14 outputs.
9
R_O
Timing resistor (R_O) input to set oscillator frequency by setting constant current charge rate
to charge capacitor C_O.
10
SYNC
For PWM controller oscillator synchronization of two or more controllers. or as a clock input
to sync oscillator from external signal.
11
OUTPUT A
A output drive of phase A from push pull transistors.
12
GND
Ground return for all input and output pins.
13
V_DD
Supplies power to operate the output drivers only.
14
OUTPUT B
Output of phase B from push pull transistors.
15
V_IN
Voltage bias supply for all TC170 circuits except the output transistors.
16
SHUTDOWN Input pin to disable both output drives to 0V OFF.
PIN CONFIGURATIONS (DIP and SOIC)
SOFT START/
ILIM 1
VREFOUT 2
– I _SENSE IN 3
+ I _SENSE IN 4
TC170
+ ERROR AMP IN 5 _CPE
– ERROR AMP IN 6
CMPTR 7
CO 8
16 SHDN
15 VIN
14 OUTPUT B
13 VDD
12 GND
11 OUTPUT A
10 SYNC
9 RO
CINT
VSS
CAZ
BUF
ACOM
CR^– _EF
CR⁺_EF
VR^– _EF
1
16 ^VDD
2
15 DIGITAL GND
3
14 CMPTR OUT
4
13 ^B
TC170COE
5
12 A
6
11 ^VI+N
7
10 ^VI–N
8
9
VR⁺_EF
NOTE: Outputs LOW in "OFF" state.
4
5
6
7
8
TELCOM SEMICONDUCTOR, INC.
4-121