HIT HA16116FPJ, HA16116FP, HA16121FP Datasheet
HA16116FP/FPJ, HA16121FP/FPJ
Switching Regulator for Chopper Type DC/DC Converter
Description
HA16116FP/FPJ and HA16121FP/FPJ are dual-channel PWM switching regulator controller ICs for use in
chopper-type DC/DC converters.
This IC series incorporates totem pole gate drive circuits to allow direct driving of a power MOS FET. The
output logic is preset for booster, step-down, or inverting control in a DC/DC converter. This logic
assumes use of an N-channel power MOS FET for booster control, and a P-channel power MOS FET for
step-down or inverting control.
HA16116 includes a built-in logic circuit for step-down control only, and one for use in both step-down
and inverting control. HA16121 has a logic circuit for booster control only and one for both step-down and
inverting control.
Both ICs have a pulse-by-pulse current limiter, which limits PWM pulse width per pulse as a means of
protecting against overcurrent, and which uses an on/off timer for intermittent operation. Unlike
conventional methods that use a latch timer for shutdown, when the pulse-by-pulse current limiter
continues operation beyond the time set in the timer, the IC is made to operate intermittently (flickering
operation), resulting in sharp vertical setting characteristics. When the overcurrent condition subsides, the
output is automatically restored to normal.
The dual control circuits in the IC output identical triangle waveforms, for completely synchronous
configuring a compact, high efficiency dual-channel DC/DC converter, with fewer external components
than were necessary previously.
Functions
• 2.5 V reference voltage (Vref) regulator
• Triangle wave form oscillator
• Dual overcurrent detector
• Dual totem pole output driver
• UVL (under voltage lock out) system
• Dual error amplifier
• Vref overvoltage detector
• Dual PWM comparator
HA16116FP/FPJ, HA16121FP/FPJ
Features
• Wide operating supply voltage range* (3.9 V to 40.0 V)
• Wide operating frequency range (600 kHz maximum operation)
• Direct power MOS FET driving (output current ±1 A peak in maximum rating)
• Pulse-by-pulse overcurrent protection circuit with intermittent operation function (When overcurrent
state continues beyond time set in timer, the IC operates intermittently to prevent excessive output
current.)
• Grounding the ON/OFF pin turns the IC off, saving power dissipation. (HA16116: I
HA16121: I
= 150 µA max.)
OFF
• Built-in UVL circuit (UVL voltage can be varied with external resistance.)
• Built-in soft start and quick shutoff functions
Note: The reference voltage 2.5 V is under the condition of VIN ≥ 4.5 V.
Ordering Information
Hitachi Control ICs for Chopper-Type DC/DC Converters
Product Channel Control Functions Overcurrent
Channels Number No. Step-Up Step-Down Inverting Output Circuits Protection
Dual HA17451 Ch 1 ❍❍ ❍Open collector SCP with timer (latch)
Ch 2 ❍❍ ❍
Single HA16114 — — ❍❍Totem pole Pulse-by-pulse
HA16120 — ❍ — — power MOS FET current limiter and
Dual HA16116 Ch 1 — ❍❍driver intermittent operation
Ch 2 — ❍ — by on/off timer
HA16121 Ch 1 — ❍❍
Ch 2 ❍ ——
= 10 µA max.;
OFF
2
Pin Arrangement
HA16116FP/FPJ, HA16121FP/FPJ
Notes:
S.GND
CT
RT
IN(+)1
IN(−)1
E/O1
DB1
CL1
OUT1
P.GND
**1
1
2
3
4
5
6
7
8
9
1
10
20
19
18
17
16
15
14
13
12
11
**2
S.V
IN
Vref
TIM
ON/OFF
IN(−)2
E/O2
Channel 2Channel 1
DB2
CL2
OUT2
2
P.V
IN
(top view)
1.2.Pins S.GND (pin 1) and P.GND (pin 10) have no direct internal interconnection.
Both pins must be connected to ground.
Pins S.V (pin 20) and P.V (pin 11) have no direct internal interconnection.
Both pins must be connected to V .
IN IN
IN
3
HA16116FP/FPJ, HA16121FP/FPJ
Pin Functions
Pin No. Symbol Function
1
1 S.GND Signal circuitry*
2C
3R
T
T
Timing capacitance (triangle wave oscillator output)
Timing resistance (for bias current synchronization)
4 IN(+)1 Error amp. noninverting input (1) Channel 1
5 IN(–)1 Error amp. inverting input (1)
6 E/O1 Error amp. output (1)
7 DB1 Dead band timer off period adjustment input (1)
8 CL1 Overcurrent detection input (1)
9 OUT1 PWM pulse output (1)
10 P.GND Output stage*1 ground
11 P.V
IN
Output stage*1 power supply input
12 OUT2 PWM pulse output (2) Channel 2
13 CL2 Overcurrent detection input (2)
14 DB2 Dead band timer off period adjustment input (2)
15 E/O2 Error amp. output (2)
16 IN(–)2 Error amp. inverting input (2)*
17 ON/OFF IC on/off switch input (off when grounded)
18 TIM Setting of intermittent operation timing when overcurrent is detected
(collector input of timer transistor)
19 Vref 2.5 V reference voltage output
20 S.V
IN
Signal circuitry*1 power supply input
Notes: 1. Here “output stage” refers to the power MOS FET driver circuits, and “signal circuitry” refers to all
other circuits on the IC. Note that this IC is not protected against reverse insertion, which can
cause breakdown of the IC between V
2. Noninverting input of the channel 2 error amp is connected internally to Vref.
ground
2
and GND. Be careful to insert the IC correctly.
IN
4
Block Diagram
HA16116FP/FPJ, HA16121FP/FPJ
11
P.V
12
OUT2
IN
0.2 V
to S.V
13
CL2
14
DB2
[Channel 2]
from
UVL
E/O2
15
Booster control only (HA16121)
Step-down control only (HA16116)
−+EA2
16
IN(−)2
17
ON/OFF
18
TIM
19
Vref
10
*
OUT2
NAND
(HA16116)
NAND
OUT1
P.GND
9
OUT1
Vref
CL2
− +
from UVL
5k
IN
V
++−
PWM COMP 2
0.8V
from UVL
−++
IN
V
PWM COMP 1
0.8V
Vref
5k
CL1
− +
+
0.2 V
EA1
−
from
IN
to S.V
UVL
8
CL1
7
DB1
6
E/O1
Step-down or inverting control
[Channel 1] (HA16116/HA16121)
5
IN(−)1
Q
4
IN(+)1
3
R
TT
2
C
UVL
UVL
output
H
OR
H
V
L
V
OVP
Latch
S
R
T
R
1.1 V
L
Triangle wave
oscillator circuit
1.6 V
1.0 V
triangle wave
Bias current
latch reset pulse
IN IN
S.V
20
voltage
band gap
reference
2.5 V output
ON/OFF
circuit
generator
V
IN
0.8V
5k
from
UVL
1
S.GND
HA16121.
*
Note: This block is AND ( ) in the case of
5
HA16116FP/FPJ, HA16121FP/FPJ
Function and Timing Chart
Relation between triangle wave and PWM output (in steady-state operation)
C triangle wave
T
Dead band
voltage
E/O Error amp output
Booster
channel
output
(HA16121-
t
ON
Ch 2) only
PWM
pulse
output
Step-down
or inverting
output
(HA16116-
Ch 1, Ch 2/
HA16121-Ch 1)
Note: On duty = t /T, where T = 1/f .
ON OSC
1.6 V typ
1.0 V typ
V (on)
IN
This pulse
is for
N-channel
t
OFF
GND (off)
power MOS
FET gate
driving.
T
This pulse
V (off)
IN
is for
P-channel
power MOS
FET gate
GND (on)
driving.
6
HA16116FP/FPJ, HA16121FP/FPJ
Determining External Component Constants (pin usage)
Constant settings are explained for the following items.
Oscillator
1.
frequency
(f ) setting
OSC
S.GND
CT
RT
IN(+)1
1
2
3
4
20
19
18
17
DC/DC converter
output voltage
2.
setting and
IN(−)1
5
16
error amp usage
E/O1
6
Channel 1
15
Dead band duty
3.
and soft start
DB1
7
Channel 2
14
setting
CL1
8
13
Output stage
circuit and
4.
power MOS FET
OUT1
9
12
driving method
1. Oscillator Frequency (f
) Setting
OSC
P.GND
10
11
Figure 1.1 shows an equivalent circuit for the triangle wave oscillator.
S.V
IN
Vref
TIM
ON/OFF
IN(−)2
E/O2
DB2
CL2
OUT2
P.V
IN
Vref UVL and
5.
OVP
Setting of intermittent operation
timing when
6.
overcurrent is
detected
ON/OFF pin
7.
usage
Overcurrent
8.
detection value
setting
V
H
1.6 V typ
V
L
t
t
1
2
1.0 V typ
1.1 V
R
(external)
R
T
T
Vref (2.5 V)
Discharging
1 : 2
charging
C
T
I
O
I
O
C
T
(external)
C
T
Comparator
(3.3 V
IC internal circuits)
R
C
Inside the IC
R
A
R
B
Figure 1.1 Equivalent Circuit for the Triangle Wave Oscillator
7
HA16116FP/FPJ, HA16121FP/FPJ
The triangle wave is a voltage waveform used as a reference in creating a PWM pulse. This block operates
according to the following principles. A constant current IO, determined by an external timing resistor RT,
is made to flow continuously to external timing capacitor CT. When the CT pin voltage exceeds the
comparator threshold voltage VH, the comparator output causes a switch to operate, discharging a current I
from CT. Next, when the CT pin voltage drops below threshold voltage VL, the comparator output again
causes the switch to operate, stopping the IO discharge. The triangle wave is generated by this repeated
operation.
O
Note that IO = 1.1 V/RT. Since the IO current mirror circuit has a very limited current producing ability, R
should be set to ≥ 5 kΩ (IO ≥ 220 µA).
With this IC series, VH and VL of the triangle wave are fixed internally at about 1.6 V and 1.0 V by the
internal resistors RA, RB, and RC. The oscillator frequency can be calculated as follows.
f
OSC
Here,
=
t
1
t
=
2
VH − V
t
= t2 = CT R
1
t3 ≈ 0.8 µs (comparator delay time in the oscillator)
Accordingly,
f
OSC
Note that the value of f
1
=
t
+ t
+ t
1
2
3
C
⋅ (VH − VL)
T
1.1 V/R
T
C
⋅ (VH − VL)
T
(2 − 1) × 1.1 V/R
= 0.6 V
L
0.6
1.1
1
≈
2t
≈
1
OSC
+ t
1.1 C
3
may differ slightly from the above calculation depending on the amount of delay
CT RT ⋅ (VH − VL)
=
T
T
1.1 V
CT RT ⋅ (VH − VL)
==
T RT
1
+ 0.8 µs
1.1 V
[Hz]
t
1
in the comparator circuit. Also, at high frequencies this comparator delay can cause triangle wave
overshoot or undershoot, skewing the dead band threshold. Confirm the actual value in implementation
and adjust the constants accordingly.
T
8
HA16116FP/FPJ, HA16121FP/FPJ
2. DC/DC Converter Output Voltage Setting and Error Amp Usage
2.1 Positive Voltage Booster (VO > VIN) or Step-Down (VIN > VO > Vref)
R1 + R
VO =Use
Booster output is possible only at channel 2 of HA16121. For step-down output, both channels of
HA16116 or channel 1 of HA16121 are used.
R
2
2
⋅ Vref (V)
V
O
R
1
R
V
2
R
R
O
1
2
Vref pin
Figure 2.1
Error amp.
IN(−)1
−
+
IN(+)1
IN(−)2
−
+
Vref
2.5 V
(internal connection)
CH1
CH2
2.2 Negative Voltage (VO < Vref) for Inverting Output
Use
VO = −Vref ⋅
R
1
R1 + R
R3 + R
⋅
2
4
− 1 (V)
R
3
Channel 1 is used for inverting output on both ICs.
Vref pin
R
1
R
R
3
2
R
4
V
O
IN(−)1
IN(+)2
Figure 2.1 Inverting Output
Vref 2.5 V
−
+
Error amp
CH1
9
HA16116FP/FPJ, HA16121FP/FPJ
2.3 Error Amplifier
Figure 2.3 shows an equivalent circuit of the error amplifier. The error amplifier on these ICs is configured
of a simple NPN transistor differential input amplifier and the output circuit of a constant-current driver.
This amplifier features wide bandwidth (fT = 4 MHz) with open loop gain kept to 50 dB, allowing stable
feedback to be applied when the power supply is designed. Phase compensation is also easy.
Both HA16116 and HA16121 have a noninverting input (IN(+)) pin, in order to allow use of the channel 1
error amplifier for inverting control. The channel 2 error amplifier, on the other hand, is used for stepdown control in HA16116 and booster control in HA16121; so the channel 2 noninverting input is
connected internally to Vref.
IC internal V
IN(−)
IN(+)
IN
E/O
To internal PWM
comparator
µµ
40 A80 A
Figure 2.3 Error Amplifier Equivalent Circuit
3. Dead Band (DB) Duty and Soft Start Setting (common to both channels)
3.1 Dead Band Duty Setting
Dead band duty is set by adjusting the DB pin input voltage (VDB). A convenient means of doing this is to
connect two external resistors to the Vref of this IC so as to divide VDB (see figure 3.1).
R
VDB = Vref
Duty (DB) =
Here, T =
f
×
R1 + R
V
TH
VTH − V
1
OSC
− V
2
(V)
2
DB
TL
⋅ ⋅ ⋅ ⋅× 100 (%) This applies when VDB > VTL.
If V
< VTL, there is no PWM output.
DB
Note: VTH: 1.6 V (Typ)
VTL: 1.0 V (Typ)
Vref is typically 2.5 V. Select R1 and R2 so that 1.0 V ≤ VDB ≤ 1.6 V.
10
HA16116FP/FPJ, HA16121FP/FPJ
V
TH
V
To Vref
V
DB
C
ST
C
T
R
1
E/O
DB
R
2
5k
PWM
comparator
−
+
+
From UVL
0.8V
V
IN
PWM
pulse
output
E/O
V
DB
V
TL
Booster
channel
Step-down/
inverting
channel
t
OFF
On
t
On
ON
Off
Off
T
Figure 3.1 Dead Band Duty Setting
3.2 Soft Start (SST) Setting (each channel)
When the power is turned on, the soft start function gradually raises VDB (refer to section 3.1), and the
PWM output pulse width gradually widens. This function is realized by adding a capacitor CST to the DB
pin. The function is realized as follows.
1.6 V typ
1.0 V typ
V
IN
GND
V
IN
GND
In the figure 3.2, the DB pin is clamped internally at approximately 0.8 V, which is 0.2 V lower than the
triangle wave VTL = 1.0 V typ.
tA: Standby time until PWM pulse starts widening.
t
: Time during which SST is in effect.
B
During soft start, the DB pin voltage in the figure below is as expressed in the following equation.
−t − t
V
SST
= VDB ⋅
1 − e,
Here,
t
= −T ln
0.8
1 − ,
How to select values: If the soft start time t
overshoot. To prevent this, set t
0.8
T
0.8
V
DB
to a few tens of ms or above.
SST
= tA + t
t
SST
T = C
⋅ (R1 // R2)
ST
is too short, the DC/DC converter output voltage will tend to
SST
B
11
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